Working to support lsp4j

app/build.gradle

@@ -1,5 +1,4 @@
 apply plugin: 'com.android.application'
-apply plugin: 'com.itsaky.androidide'
 apply plugin: 'com.google.gms.google-services'
 apply plugin: 'com.google.firebase.crashlytics'
 apply plugin: 'stringfog'
@@ -136,6 +135,8 @@ dependencies {
     implementation project(':emulator')
     implementation project(':emulatorview')
     implementation project(':javapoet')
+    
+    implementation 'org.eclipse.lsp4j:org.eclipse.lsp4j:0.12.0'
 	
 	implementation fileTree(dir: 'libs', include: ['*.jar'])
 	

app/src/main/java/com/itsaky/androidide/EditorActivity.java

@@ -31,6 +31,8 @@ import com.google.android.material.dialog.MaterialAlertDialogBuilder;
 import com.google.android.material.navigation.NavigationView;
 import com.google.android.material.tabs.TabLayout;
 import com.google.android.material.transition.MaterialContainerTransform;
+import com.google.gson.JsonArray;
+import com.google.gson.JsonObject;
 import com.google.gson.JsonParser;
 import com.itsaky.androidide.adapters.EditorPagerAdapter;
 import com.itsaky.androidide.app.StudioActivity;
@@ -48,8 +50,11 @@ import com.itsaky.androidide.handlers.IDEHandler;
 import com.itsaky.androidide.handlers.jls.JLSHandler;
 import com.itsaky.androidide.handlers.jls.LanguageClientHandler;
 import com.itsaky.androidide.interfaces.DiagnosticClickListener;
+import com.itsaky.androidide.interfaces.EditorActivityProvider;
 import com.itsaky.androidide.language.buildout.BuildOutputLanguage;
 import com.itsaky.androidide.language.logs.LogLanguageImpl;
+import com.itsaky.androidide.lsp.LSP;
+import com.itsaky.androidide.lsp.LSPProvider;
 import com.itsaky.androidide.managers.PreferenceManager;
 import com.itsaky.androidide.managers.VersionedFileManager;
 import com.itsaky.androidide.models.AndroidProject;
@@ -85,10 +90,16 @@ import java.io.File;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Stack;
 import java.util.regex.Pattern;
 import me.piruin.quickaction.ActionItem;
 import me.piruin.quickaction.QuickAction;
+import org.eclipse.lsp4j.DidChangeConfigurationParams;
+import org.eclipse.lsp4j.InitializeResult;
+import org.eclipse.lsp4j.services.LanguageServer;
+import org.eclipse.lsp4j.Position;
+import com.itsaky.androidide.utils.LSPUtils;
 
 public class EditorActivity extends StudioActivity implements FileTreeFragment.FileActionListener,
 														TabLayout.OnTabSelectedListener,
@@ -96,7 +107,8 @@ public class EditorActivity extends StudioActivity implements FileTreeFragment.F
                                                         DiagnosticClickListener, 
                                                         EditorFragment.FileOpenListener,
                                                         EditorPagerAdapter.EditorStateListener,
-                                                        IDEHandler.Provider {
+                                                        IDEHandler.Provider,
+                                                        EditorActivityProvider {
     
     private ActivityEditorBinding mBinding;
 	private EditorPagerAdapter mPagerAdapter;
@@ -131,6 +143,8 @@ public class EditorActivity extends StudioActivity implements FileTreeFragment.F
     
 	private static final String TAG_FILE_OPTIONS_FRAGMENT = "file_options_fragment";
     public static final String TAG = "EditorActivity";
+    
+    private static final org.eclipse.lsp4j.Range Range_ofZero = new org.eclipse.lsp4j.Range(new Position(0, 0), new Position(0, 0));
 	
 	private static final int ACTIONID_CLOSE = 100;
 	private static final int ACTIONID_OTHERS = 101;
@@ -204,6 +218,8 @@ public class EditorActivity extends StudioActivity implements FileTreeFragment.F
 		registerLogReceiver();
 		setupContainers();
         setupSignatureText();
+        
+        startLanguageServers();
     }
     
 	@Override
@@ -380,6 +396,11 @@ public class EditorActivity extends StudioActivity implements FileTreeFragment.F
 		invalidateOptionsMenu();
 		return true;
 	}
+
+    @Override
+    public EditorActivity provide() {
+        return this;
+    }
     
     @Override
     public EditorActivity provideEditorActivity() {
@@ -592,7 +613,7 @@ public class EditorActivity extends StudioActivity implements FileTreeFragment.F
 
     @Override
     public void onDiagnosticClick(File file, Diagnostic diagnostic) {
-        openFileAndSelect(file, diagnostic.range);
+//        openFileAndSelect(file, diagnostic.getRange());
         hideDiagnostics();
     }
 
@@ -639,16 +660,16 @@ public class EditorActivity extends StudioActivity implements FileTreeFragment.F
         }
     }
 
-    public void openFileAndSelect(File file, Range range) {
+    public void openFileAndSelect(File file, org.eclipse.lsp4j.Range range) {
         openFile(file, range);
         EditorFragment opened = mPagerAdapter.findEditorByFile(file);
         if (opened != null && opened.getEditor() != null) {
             CodeEditor editor = opened.getEditor();
             editor.post(() -> {
-                if (range.start.equals(range.end)) {
-                    editor.setSelection(range.start.line, range.start.column);
+                if (LSPUtils.isEqual(range.getStart(), range.getEnd())) {
+                    editor.setSelection(range.getStart().getLine(), range.getEnd().getCharacter());
                 } else {
-                    editor.setSelectionRegion(range.start.line, range.start.column, range.end.line, range.end.column);
+                    editor.setSelectionRegion(range.getStart().getLine(), range.getStart().getCharacter(), range.getEnd().getLine(), range.getEnd().getCharacter());
                 }
             });
         }
@@ -867,8 +888,8 @@ public class EditorActivity extends StudioActivity implements FileTreeFragment.F
         openFile(file, null);
     }
 
-    public EditorFragment openFile(File file, Range selection) {
-        if(selection == null) selection = Range.ofZero();
+    public EditorFragment openFile(File file, org.eclipse.lsp4j.Range selection) {
+        if(selection == null) selection = Range_ofZero;
         int i = mPagerAdapter.openFile(file, selection, this, mJLSHandler);
         if(i >= 0 && !mBinding.tabs.getTabAt(i).isSelected())
             mBinding.tabs.getTabAt(i).select();
@@ -935,7 +956,27 @@ public class EditorActivity extends StudioActivity implements FileTreeFragment.F
     public void createServices() {
         new TaskExecutor().executeAsync(() -> {
             getApp().createCompletionService();
-            mJLSHandler.start();
+            
+            LanguageServer javaServer = LSPProvider.getServerForLanguage(LSPProvider.LANGUAGE_JAVA);
+            if(javaServer == null) return null;
+            
+            List<String> cps = mProject.getClassPaths();
+            JsonObject settings = new JsonObject();
+            JsonObject java = new JsonObject();
+            JsonArray classPath = new JsonArray();
+            
+            for(int i=0;i<cps.size();i++) {
+                classPath.add(cps.get(i));
+            }
+            
+            java.add("classPath", classPath);
+            settings.add("java", java);
+            
+            DidChangeConfigurationParams params = new DidChangeConfigurationParams();
+            params.setSettings(settings);
+            
+            javaServer.getWorkspaceService().didChangeConfiguration(params);
+            
             return null;
         }, __ -> {
             setStatus(getString(getApp().areCompletorsStarted() ? R.string.msg_service_started : R.string.msg_starting_completion_failed));
@@ -997,6 +1038,19 @@ public class EditorActivity extends StudioActivity implements FileTreeFragment.F
       ////////////// PRIVATE APIS /////////////////////
      /////////////////////////////////////////////////
      
+    private void startLanguageServers() {
+        LSP.Java.start(() -> {
+            Optional<InitializeResult> result = LSP.Java.init(mProject.getProjectPath());
+
+            if(result.isPresent()) {
+                // TODO Handle initialize result
+                // TODO Register server capablities
+            } else if(true) {
+                // TODO Show user that we cant initialize Java language server
+            }
+        });
+    }
+    
     private void getProjectFromIntent() {
         this.mProject = getIntent().getParcelableExtra(EXTRA_PROJECT);
         getApp().getPrefManager().setOpenedProject(this.mProject.getProjectPath());

app/src/main/java/com/itsaky/androidide/adapters/CompletionListAdapter.java

@@ -9,6 +9,7 @@ import android.view.ViewGroup;
 import android.widget.TextView;
 import androidx.core.content.ContextCompat;
 import com.blankj.utilcode.util.ThreadUtils;
+import com.google.gson.Gson;
 import com.google.gson.JsonArray;
 import com.google.gson.JsonElement;
 import com.google.gson.JsonObject;
@@ -18,7 +19,6 @@ import com.itsaky.androidide.databinding.LayoutCompletionItemBinding;
 import com.itsaky.androidide.models.CompletionItemWrapper;
 import com.itsaky.androidide.models.CompletionListItem;
 import com.itsaky.androidide.models.SuggestItem;
-import com.itsaky.androidide.utils.Either;
 import com.itsaky.androidide.utils.Logger;
 import com.itsaky.androidide.utils.TypefaceUtils;
 import com.itsaky.apiinfo.ApiInfo;
@@ -26,10 +26,10 @@ import com.itsaky.apiinfo.models.ClassInfo;
 import com.itsaky.apiinfo.models.FieldInfo;
 import com.itsaky.apiinfo.models.Info;
 import com.itsaky.apiinfo.models.MethodInfo;
-import com.itsaky.lsp.CompletionItemKind;
-import io.github.rosemoe.editor.struct.CompletionItem;
 import io.github.rosemoe.editor.widget.EditorCompletionAdapter;
 import java.util.Locale;
+import org.eclipse.lsp4j.CompletionItem;
+import org.eclipse.lsp4j.CompletionItemKind;
 
 public class CompletionListAdapter extends EditorCompletionAdapter {
     
@@ -44,23 +44,10 @@ public class CompletionListAdapter extends EditorCompletionAdapter {
     protected View getView(int position, View convertView, ViewGroup parent, boolean isCurrentCursorPosition) {
         LayoutCompletionItemBinding binding = LayoutCompletionItemBinding.inflate(LayoutInflater.from(getContext()), parent, false);
 
-		Either<SuggestItem, CompletionItem> e = getItem(position);
-		String label = "", desc = "", type = "";
-		String header = "";
-		if (e != null && e.isLeft()) {
-			SuggestItem s = e.getLeft();
-			label = s.getName();
-			desc = s.getDescription();
-			type = s.getReturnType();
-			header = String.valueOf(s.getTypeHeader()).toUpperCase(Locale.US);
-		} else if (e != null && e.isRight()) {
-			CompletionListItem item = (CompletionListItem) e.getRight();
-			header = item.getType() == null ? CompletionListItem.Type.OBJECT.getAsString() :  item.getType().getAsString();
-			label = item.getLabel();
-			type = item.getItemType().contains(".") ? item.getItemType().substring(item.getItemType().lastIndexOf(".") + 1) : item.getItemType();
-			desc = item.getType() != CompletionListItem.Type.NOT_IMPORTED_CLASS ? item.getDetail() : getContext().getString(R.string.label_not_imported, item.getDetail());
-		}
-
+		CompletionItem item = getItem(position);
+		String label = item.getLabel(), desc = item.getDetail(), type = item.getKind().toString();
+		String header = type == null || type.length() <= 0 ? "O" : String.valueOf(type.toString().charAt(0));
+		
         binding.completionIconText.setText(header);
         binding.completionLabel.setText(label);
         binding.completionType.setText(type);
@@ -75,8 +62,8 @@ public class CompletionListAdapter extends EditorCompletionAdapter {
 
         binding.completionApiInfo.setVisibility(View.GONE);
         
-        if (e != null && e.isLeft() && e.getLeft() instanceof CompletionItemWrapper) {
-            showApiInfoIfNeeded((CompletionItemWrapper) e.getLeft(), binding.completionApiInfo);
+        if (item != null) {
+            showApiInfoIfNeeded(item, binding.completionApiInfo);
         }
         
         binding.getRoot().getViewTreeObserver().addOnGlobalLayoutListener(() -> {
@@ -89,22 +76,22 @@ public class CompletionListAdapter extends EditorCompletionAdapter {
         return binding.getRoot();
     }
 
-    private void showApiInfoIfNeeded(final CompletionItemWrapper item, final TextView completionApiInfo) {
+    private void showApiInfoIfNeeded(final CompletionItem item, final TextView completionApiInfo) {
         
         new Thread(() -> {
             final ApiInfo info = StudioApp.getInstance().getApiInfo();
             boolean hasRead = info != null && info.hasRead();
-            boolean isValid = isValidForApiVersion(item.getItem());
+            boolean isValid = isValidForApiVersion(item);
             
             if (hasRead && isValid) {
 
-                JsonElement element = item.getItem().data;
+                JsonElement element = new Gson().toJsonTree(item.getData());
                 if (element == null || !element.isJsonObject()) return;
                 JsonObject data = element.getAsJsonObject();
                 if (!data.has("className")) return;
                 
                 final String className = data.get("className").getAsString();
-                int kind = item.getItem().kind;
+                CompletionItemKind kind = item.getKind();
                 
                 ClassInfo clazz = info.getClassByName(className);
                 if(clazz == null) return;
@@ -168,10 +155,10 @@ public class CompletionListAdapter extends EditorCompletionAdapter {
         }).start();
     }
 
-    private boolean isValidForApiVersion(com.itsaky.lsp.CompletionItem item) {
+    private boolean isValidForApiVersion(CompletionItem item) {
         if (item == null) return false;
-        final int type = item.kind;
-        JsonElement element = item.data;
+        final CompletionItemKind type = item.getKind();
+        JsonElement element = new Gson().toJsonTree(item.getData());
         if (
         
         /**

app/src/main/java/com/itsaky/androidide/adapters/EditorPagerAdapter.java

@@ -66,7 +66,7 @@ public class EditorPagerAdapter extends FragmentStatePagerAdapter implements Edi
         return null;
     }
 
-	public int openFile(File file, Range selection, EditorFragment.FileOpenListener listener, JLSRequestor jlsRequestor) {
+	public int openFile(File file, org.eclipse.lsp4j.Range selection, EditorFragment.FileOpenListener listener, JLSRequestor jlsRequestor) {
 		int openedFileIndex = -1;
 		for (int i=0;i < mOpenedFiles.size();i++) {
 			File f = mOpenedFiles.get(i);

app/src/main/java/com/itsaky/androidide/fragments/EditorFragment.java

@@ -44,6 +44,7 @@ import java.util.Map;
 import org.antlr.v4.runtime.CharStreams;
 import org.antlr.v4.runtime.Token;
 import io.github.rosemoe.editor.text.Content;
+import com.itsaky.androidide.utils.LSPUtils;
 
 public class EditorFragment extends BaseFragment implements EditorEventListener {
 	
@@ -104,13 +105,13 @@ public class EditorFragment extends BaseFragment implements EditorEventListener
         }
     }
     
-	public static EditorFragment newInstance(File file, AndroidProject project, Range selection) {
+	public static EditorFragment newInstance(File file, AndroidProject project, org.eclipse.lsp4j.Range selection) {
 		Bundle bundle = new Bundle();
 		bundle.putString(KEY_FILE_PATH, file.getAbsolutePath());
-        bundle.putInt(KEY_LINE_START, selection.start.line);
-        bundle.putInt(KEY_LINE_END, selection.end.line);
-        bundle.putInt(KEY_COLUMN_START, selection.start.column);
-        bundle.putInt(KEY_COLUMN_END, selection.end.column);
+        bundle.putInt(KEY_LINE_START, selection.getStart().getLine());
+        bundle.putInt(KEY_LINE_END, selection.getEnd().getLine());
+        bundle.putInt(KEY_COLUMN_START, selection.getStart().getCharacter());
+        bundle.putInt(KEY_COLUMN_END, selection.getEnd().getCharacter());
 		bundle.putParcelable(KEY_PROJECT, project);
 		EditorFragment frag = new EditorFragment();
 		frag.setArguments(bundle);
@@ -164,32 +165,32 @@ public class EditorFragment extends BaseFragment implements EditorEventListener
         
 		configureEditorIfNeeded();
 		
-        final Range range = fromArgs(getArguments());
+        final org.eclipse.lsp4j.Range range = fromArgs(getArguments());
 		new TaskExecutor().executeAsync(new ReadFileTask(mFile), result -> {
 			mBinding.editor.setText(result);
 			postRead();
             mBinding.editor.post(() -> {
-                if(range.start.equals(range.end)) {
-                    getEditor().setSelection(range.start.line, range.start.column);
+                if(LSPUtils.isEqual(range.getStart(), range.getEnd())) {
+                    getEditor().setSelection(range.getStart().getLine(), range.getStart().getCharacter());
                 } else {
-                    getEditor().setSelectionRegion(range.start.line, range.start.column, range.end.line, range.end.column);
+                    getEditor().setSelectionRegion(range.getStart().getLine(), range.getStart().getCharacter(), range.getEnd().getLine(), range.getEnd().getCharacter());
                 }
             });
 		});
 	}
 
-    private Range fromArgs(Bundle args) {
+    private org.eclipse.lsp4j.Range fromArgs(Bundle args) {
         if(!(args.containsKey(KEY_LINE_START)
          && args.containsKey(KEY_COLUMN_START)
          && args.containsKey(KEY_LINE_END)
          && args.containsKey(KEY_COLUMN_END)))
-            return Range.ofZero();
+            return LSPUtils.Range_ofZero;
             
-        return new Range(
-            new Position(
+        return new org.eclipse.lsp4j.Range(
+            new org.eclipse.lsp4j.Position(
                 args.getInt(KEY_LINE_START),
                 args.getInt(KEY_COLUMN_START)),
-            new Position(
+            new org.eclipse.lsp4j.Position(
                 args.getInt(KEY_LINE_END),
                 args.getInt(KEY_COLUMN_END)
                 ));
@@ -302,7 +303,6 @@ public class EditorFragment extends BaseFragment implements EditorEventListener
 	}
 	
 	private void postRead() {
-        mBinding.editor.setFile(getFile());
 		if (mFile.isFile() && mFile.getName().endsWith(EXT_JAVA)) {
 			mBinding.editor.setEditorLanguage(mJavaLanguage = new JavaLanguage(mProject));
 		} else if (mFile.isFile() && mFile.getName().endsWith(EXT_XML)) {
@@ -312,6 +312,11 @@ public class EditorFragment extends BaseFragment implements EditorEventListener
 		} else {
 			mBinding.editor.setEditorLanguage(new EmptyLanguage());
 		}
+        
+        // File must be set only after setting the language server
+        // This will make sure that textDocument/didOpen is sent
+        mBinding.editor.setFile(getFile());
+        
         mBinding.editor.setColorScheme(new SchemeAndroidIDE());
 		isRead = true;
         if(mOpenListener != null)
@@ -427,16 +432,7 @@ public class EditorFragment extends BaseFragment implements EditorEventListener
 	}
     
     private void notifySaved(boolean wrote, String text) {
-        if (wrote && mJLSRequestor != null) {
-            try {
-                TextDocumentIdentifier id = new TextDocumentIdentifier();
-                id.uri = mFile.toURI();
-                DidSaveTextDocumentParams p = new DidSaveTextDocumentParams();
-                p.text = text;
-                p.textDocument = id;
-                mJLSRequestor.didSave(p);
-            } catch (Throwable th) {}
-        }
+        mBinding.editor.didSave();
         
         if(mModificationStateListener != null)
             mModificationStateListener.onSaved(this);

app/src/main/java/com/itsaky/androidide/handlers/jls/JLSHandler.java

@@ -65,7 +65,7 @@ public class JLSHandler extends IDEHandler implements JLSRequestor {
         this.client.start();
         
         this.languageServer = new JavaLanguageServer(project, this.client);
-        this.languageServer.startServer();
+//        this.languageServer.startServer();
         
         StudioApp.getInstance().setJavaLanguageServer(languageServer);
     }

app/src/main/java/com/itsaky/androidide/handlers/jls/LanguageClientHandler.java

@@ -6,7 +6,6 @@ import android.view.View;
 import com.blankj.utilcode.util.FileIOUtils;
 import com.blankj.utilcode.util.ThrowableUtils;
 import com.google.gson.JsonElement;
-import com.itsaky.androidide.EditorActivity;
 import com.itsaky.androidide.R;
 import com.itsaky.androidide.adapters.DiagnosticsAdapter;
 import com.itsaky.androidide.adapters.SearchListAdapter;
@@ -24,7 +23,6 @@ import com.itsaky.lsp.Location;
 import com.itsaky.lsp.Message;
 import com.itsaky.lsp.ParameterInformation;
 import com.itsaky.lsp.PublishDiagnosticsParams;
-import com.itsaky.lsp.Range;
 import com.itsaky.lsp.ShowMessageParams;
 import com.itsaky.lsp.SignatureHelp;
 import com.itsaky.lsp.SignatureInformation;
@@ -82,31 +80,7 @@ public class LanguageClientHandler extends IDEHandler implements LanguageClient
             activity().getApp().toast(R.string.msg_no_definition, Toaster.Type.ERROR);
             return;
         }
-        Location loc = locations.get(0);
-        final File file = new File(loc.uri);
-        final Range range = loc.range;
-        try {
-            if(activity().getPagerAdapter() == null) return;
-            if(activity().getPagerAdapter().getCount() <= 0) {
-                activity().openFile(file, range);
-                return;
-            }
-            EditorFragment frag = activity().getPagerAdapter().getFrag(activity().getBinding().tabs.getSelectedTabPosition());
-            if(frag != null
-               && frag.getFile() != null
-               && frag.getEditor() != null
-               && frag.getFile().getAbsolutePath().equals(file.getAbsolutePath())) {
-                if(range.start.equals(range.end)) {
-                    frag.getEditor().setSelection(range.start.line, range.start.column);
-                } else {
-                    frag.getEditor().setSelectionRegion(range.start.line, range.start.column, range.end.line, range.end.column);
-                }
-            } else {
-                activity().openFileAndSelect(file, range);
-            }
-        } catch (Throwable th) {
-            LOG.error(ThrowableUtils.getFullStackTrace(th));
-        }
+        
     }
 
     @Override
@@ -125,36 +99,36 @@ public class LanguageClientHandler extends IDEHandler implements LanguageClient
         }
 
         final Map<File, List<SearchResult>> results = new HashMap<>();
-        for(int i=0;i<references.size();i++) {
-            try {
-                final Location loc = references.get(i);
-                if(loc == null || loc.uri == null || loc.range == null) continue;
-                final File file = new File(loc.uri);
-                if(!file.exists() || !file.isFile()) continue;
-                EditorFragment frag = activity().getPagerAdapter().findEditorByFile(file);
-                Content content;
-                if(frag != null && frag.getEditor() != null)
-                    content = frag.getEditor().getText();
-                else content = new Content(null, FileIOUtils.readFile2String(file));
-                final List<SearchResult> matches = results.containsKey(file) ? results.get(file) : new ArrayList<>();
-                matches.add(
-                    new SearchResult(
-                        loc.range,
-                        file,
-                        content.getLineString(loc.range.start.line),
-                        content.subContent(
-                            loc.range.start.line,
-                            loc.range.start.column,
-                            loc.range.end.line,
-                            loc.range.end.column
-                        ).toString()
-                    )
-                );
-                results.put(file, matches);
-            } catch (Throwable th) {
-                LOG.error(ThrowableUtils.getFullStackTrace(th));
-            }
-        }
+//        for(int i=0;i<references.size();i++) {
+//            try {
+//                final Location loc = references.get(i);
+//                if(loc == null || loc.uri == null || loc.range == null) continue;
+//                final File file = new File(loc.uri);
+//                if(!file.exists() || !file.isFile()) continue;
+//                EditorFragment frag = activity().getPagerAdapter().findEditorByFile(file);
+//                Content content;
+//                if(frag != null && frag.getEditor() != null)
+//                    content = frag.getEditor().getText();
+//                else content = new Content(null, FileIOUtils.readFile2String(file));
+//                final List<SearchResult> matches = results.containsKey(file) ? results.get(file) : new ArrayList<>();
+//                matches.add(
+//                    new SearchResult(
+//                        loc.range,
+//                        file,
+//                        content.getLineString(loc.range.start.line),
+//                        content.subContent(
+//                            loc.range.start.line,
+//                            loc.range.start.column,
+//                            loc.range.end.line,
+//                            loc.range.end.column
+//                        ).toString()
+//                    )
+//                );
+//                results.put(file, matches);
+//            } catch (Throwable th) {
+//                LOG.error(ThrowableUtils.getFullStackTrace(th));
+//            }
+//        }
 
         activity().handleSearchResults(results);
     }

app/src/main/java/com/itsaky/androidide/interfaces/EditorActivityProvider.java

@@ -0,0 +1,12 @@
+package com.itsaky.androidide.interfaces;
+
+import com.itsaky.androidide.EditorActivity;
+
+public interface EditorActivityProvider {
+    
+    /**
+     * Provides a reference to {@link com.itsaky.androidide.EditorActivity EditorActivity}.
+     * This is used by LanguageClients to get reference to EditorActivity without keeping a strong reference.
+     */
+    EditorActivity provide();
+}

app/src/main/java/com/itsaky/androidide/language/buildout/BuildOutputLanguage.java

@@ -11,6 +11,7 @@ import io.github.rosemoe.editor.interfaces.AutoCompleteProvider;
 import io.github.rosemoe.editor.interfaces.NewlineHandler;
 import io.github.rosemoe.editor.widget.SymbolPairMatch;
 import io.github.rosemoe.editor.langs.EmptyLanguage;
+import org.eclipse.lsp4j.services.LanguageServer;
 
 public class BuildOutputLanguage extends BaseLanguage {
 
@@ -19,6 +20,16 @@ public class BuildOutputLanguage extends BaseLanguage {
         return new EmptyLanguage.EmptyAutoCompleteProvider();
     }
 
+    @Override
+    public LanguageServer getLanguageServer() {
+        return null;
+    }
+
+    @Override
+    public String getLanguageCode() {
+        return null;
+    }
+
     @Override
     public boolean isAutoCompleteChar(char ch) {
         return false;

app/src/main/java/com/itsaky/androidide/language/groovy/GroovyAutoComplete.java

@@ -2,51 +2,54 @@ package com.itsaky.androidide.language.groovy;
 
 import com.itsaky.androidide.models.GradleSuggestItem;
 import com.itsaky.androidide.models.SuggestItem;
-import com.itsaky.androidide.utils.Either;
 import io.github.rosemoe.editor.interfaces.AutoCompleteProvider;
-import io.github.rosemoe.editor.struct.CompletionItem;
 import io.github.rosemoe.editor.text.TextAnalyzeResult;
 import io.github.rosemoe.editor.widget.CodeEditor;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Locale;
+import org.eclipse.lsp4j.CompletionItem;
+import org.eclipse.lsp4j.jsonrpc.messages.Either;
+import org.eclipse.lsp4j.InsertTextFormat;
+import org.eclipse.lsp4j.CompletionItemKind;
 
 public class GroovyAutoComplete implements AutoCompleteProvider {
 	
 	private static final List<String> ANDROIDX_ARTIFACTS = createArtifacts();
 	private static final List<String> CONFIGURATIONS = createConfigs();
 	private static final List<String> OTHERS = createOtherCompletions();
-	
-	@Override
-	public List<Either<SuggestItem, CompletionItem>> getAutoCompleteItems(CodeEditor editor, String prefix, boolean isInCodeBlock, TextAnalyzeResult colors, int line) {
-		List<Either<SuggestItem, CompletionItem>>  result = new ArrayList<>();
-		
-		for(String artifact : ANDROIDX_ARTIFACTS) {
-			if(!artifact.toLowerCase(Locale.US).startsWith(prefix.toLowerCase(Locale.US))) continue;
-			SuggestItem item = createCompletionItem(artifact, prefix, true);
-			Either<SuggestItem, CompletionItem> either = Either.forLeft(item);
-			result.add(either);
-		}
-		
-		for(String config : CONFIGURATIONS) {
-			if(!config.toLowerCase(Locale.US).startsWith(prefix.toLowerCase(Locale.US))) continue;
-			SuggestItem item = createCompletionItem(config, prefix, false);
-			Either<SuggestItem, CompletionItem> either = Either.forLeft(item);
-			result.add(either);
-		}
-		
-		for(String other : OTHERS) {
-			if(!other.toLowerCase(Locale.US).startsWith(prefix.toLowerCase(Locale.US))) continue;
-			SuggestItem item = createCompletionItem(other, prefix, false);
-			Either<SuggestItem, CompletionItem> either = Either.forLeft(item);
-			result.add(either);
-		}
-		
-		return result;
-	}
 
-	private SuggestItem createCompletionItem(String itemLabel, String prefix, boolean artifact) {
-		return new GradleSuggestItem(itemLabel, "", prefix, artifact);
+    @Override
+    public List<CompletionItem> getAutoCompleteItems(String fileUri, String prefix, boolean isInCodeBlock, TextAnalyzeResult colors, int index, int line, int column) throws Exception {
+        List<CompletionItem>  result = new ArrayList<>();
+
+        for(String artifact : ANDROIDX_ARTIFACTS) {
+            if(!artifact.toLowerCase(Locale.US).startsWith(prefix.toLowerCase(Locale.US))) continue;
+            result.add(createCompletionItem(artifact, prefix, true));
+        }
+
+        for(String config : CONFIGURATIONS) {
+            if(!config.toLowerCase(Locale.US).startsWith(prefix.toLowerCase(Locale.US))) continue;
+            result.add(createCompletionItem(config, prefix, false));
+        }
+
+        for(String other : OTHERS) {
+            if(!other.toLowerCase(Locale.US).startsWith(prefix.toLowerCase(Locale.US))) continue;
+            result.add(createCompletionItem(other, prefix, false));
+        }
+
+		return result;
+    }
+    
+	private CompletionItem createCompletionItem(String itemLabel, String prefix, boolean artifact) {
+        CompletionItem item = new CompletionItem();
+        item.setLabel(itemLabel);
+        item.setDetail("");
+        item.setInsertText(itemLabel);
+        item.setSortText("0" + itemLabel);
+        item.setInsertTextFormat(InsertTextFormat.PlainText);
+        item.setKind(CompletionItemKind.Text);
+		return item;
 	}
 	
 	private static List<String> createArtifacts() {

app/src/main/java/com/itsaky/androidide/language/groovy/GroovyLanguage.java

@@ -3,6 +3,7 @@ package com.itsaky.androidide.language.groovy;
 import com.itsaky.androidide.language.BaseLanguage;
 import com.itsaky.androidide.language.groovy.lexer.GroovyLexer;
 import com.itsaky.androidide.language.java.manager.JavaCharacter;
+import com.itsaky.androidide.lsp.LSPProvider;
 import io.github.rosemoe.editor.interfaces.AutoCompleteProvider;
 import io.github.rosemoe.editor.interfaces.CodeAnalyzer;
 import io.github.rosemoe.editor.interfaces.NewlineHandler;
@@ -11,6 +12,7 @@ import io.github.rosemoe.editor.widget.SymbolPairMatch;
 import java.io.StringReader;
 import org.antlr.v4.runtime.CharStreams;
 import org.antlr.v4.runtime.Token;
+import org.eclipse.lsp4j.services.LanguageServer;
 
 public class GroovyLanguage extends BaseLanguage {
 	
@@ -21,6 +23,16 @@ public class GroovyLanguage extends BaseLanguage {
 		analyzer = new GroovyAnalyzer();
 		completor = new GroovyAutoComplete();
 	}
+
+    @Override
+    public LanguageServer getLanguageServer() {
+        return null;
+    }
+
+    @Override
+    public String getLanguageCode() {
+        return LSPProvider.LANGUAGE_GROOVY;
+    }
 	
 	@Override
 	public CodeAnalyzer getAnalyzer() {

app/src/main/java/com/itsaky/androidide/language/java/JavaAutoComplete.java

@@ -1,67 +1,77 @@
 package com.itsaky.androidide.language.java;
 
-import androidx.core.util.Pair;
-import com.itsaky.androidide.app.StudioApp;
-import com.itsaky.androidide.language.java.JavaLanguageAnalyzer;
-import com.itsaky.androidide.language.java.server.JavaLanguageServer;
-import com.itsaky.androidide.models.CompletionItemWrapper;
-import com.itsaky.androidide.models.SuggestItem;
-import com.itsaky.androidide.utils.Either;
-import com.itsaky.lsp.CompletionList;
-import com.itsaky.lsp.Position;
-import com.itsaky.lsp.TextDocumentIdentifier;
-import com.itsaky.lsp.TextDocumentPositionParams;
+import com.itsaky.androidide.utils.Logger;
 import io.github.rosemoe.editor.interfaces.AutoCompleteProvider;
-import io.github.rosemoe.editor.struct.CompletionItem;
 import io.github.rosemoe.editor.text.TextAnalyzeResult;
 import io.github.rosemoe.editor.widget.CodeEditor;
 import java.util.ArrayList;
-import java.util.List;
 import java.util.Collections;
 import java.util.Comparator;
+import java.util.List;
+import java.util.concurrent.CompletableFuture;
+import org.eclipse.lsp4j.CompletionItem;
+import org.eclipse.lsp4j.CompletionList;
+import org.eclipse.lsp4j.CompletionParams;
+import org.eclipse.lsp4j.Position;
+import org.eclipse.lsp4j.TextDocumentIdentifier;
+import org.eclipse.lsp4j.jsonrpc.messages.Either;
+import org.eclipse.lsp4j.services.LanguageServer;
+import com.itsaky.androidide.utils.JSONUtility;
 
 public class JavaAutoComplete implements AutoCompleteProvider {
     
-	private JavaLanguageAnalyzer analyzer;
-    private int lastId = -1;
+	private JavaLanguage language;
+    private CompletableFuture<Either<List<CompletionItem>, CompletionList>> future;
     
-	public JavaAutoComplete(JavaLanguageAnalyzer analyzer) {
-		this.analyzer = analyzer;
+	public JavaAutoComplete(JavaLanguage lang) {
+		this.language = lang;
 	}
 
 	@Override
-	public List<Either<SuggestItem, CompletionItem>> getAutoCompleteItems(CodeEditor editor, String prefix, boolean isInCodeBlock, TextAnalyzeResult colors, int line) {
-        final JavaLanguageServer server = StudioApp.getInstance().getJavaLanguageServer();
-        if(server != null) {
-            if(lastId != -1) server.cancelRequest(lastId);
-            TextDocumentIdentifier id = new TextDocumentIdentifier();
-            id.uri = editor.getFile().toURI();
-            TextDocumentPositionParams p = new TextDocumentPositionParams();
-            p.position = new Position(line, editor.getCursor().getLeftColumn());
-            p.textDocument = id;
-            Pair<Integer, CompletionList> response = server.completion(p);
-            lastId = response.first;
-            CompletionList list = response.second;
-            if(list != null && list.items != null) {
-                List<Either<SuggestItem, CompletionItem>> result = new ArrayList<>();
-                for(int i=0;i<list.items.size();i++) {
-                    com.itsaky.lsp.CompletionItem item = list.items.get(i);
-                    if(item == null) continue;
-                    Either<SuggestItem, CompletionItem> either = Either.forLeft(new CompletionItemWrapper(item, prefix));
-                    result.add(either);
-                }
-                Collections.sort(result, RESULT_SORTER);
-                return result;
+	public List<CompletionItem> getAutoCompleteItems(String fileUri, String prefix, boolean isInCodeBlock, TextAnalyzeResult colors, int index, int line, int column) throws Exception {
+        LanguageServer languageServer = language.getLanguageServer();
+        if(languageServer != null && fileUri != null) {
+            
+            if(future != null && !future.isDone()) future.cancel(true);
+            
+            CompletionParams params = new CompletionParams();
+            params.setPosition(new Position(line, column));
+            params.setTextDocument(new TextDocumentIdentifier(fileUri));
+            future = languageServer.getTextDocumentService().completion(params);
+            
+            if(future.isCancelled()) return new ArrayList<CompletionItem>();
+            
+            try {
+                Either<List<CompletionItem>, CompletionList> either = future.get();
+                if(either.isLeft())
+                    return sort(either.getLeft());
+                
+                if(either.isRight())
+                    return sort(either.getRight().getItems());
+                
+            } catch (Throwable th) {
+                LOG.error("Java completion error: ", th);
+                // Ignore this exception. An empty list will be sent after this
+                // This exeption is thrown probably because the request was cancelled or interrupted
             }
         }
-        return new ArrayList<Either<SuggestItem, CompletionItem>>();
+        return new ArrayList<CompletionItem>();
 	}
     
-    private static final Comparator<Either<SuggestItem, CompletionItem>> RESULT_SORTER = new Comparator<Either<SuggestItem, CompletionItem>>(){
-
+    private List<CompletionItem> sort(List<CompletionItem> items) {
+        Collections.sort(items, RESULT_SORTER);
+        return items;
+    }
+    
+    private static final Comparator<CompletionItem> RESULT_SORTER = new Comparator<CompletionItem>(){
+        
         @Override
-        public int compare(Either<SuggestItem, CompletionItem> p1, Either<SuggestItem, CompletionItem> p2) {
-            return p1.getLeft().getSortText().compareTo(p2.getLeft().getSortText());
+        public int compare(CompletionItem p1, CompletionItem p2) {
+            String s1 = p1.getSortText() == null ? p1.getLabel() : p1.getSortText();
+            String s2 = p2.getSortText() == null ? p2.getLabel() : p2.getSortText();
+            return s1.compareTo(s2);
         }
     };
+    
+    private static final Logger LOG = Logger.instance("JavaAutoComplete");
 }

app/src/main/java/com/itsaky/androidide/language/java/JavaLanguage.java

@@ -4,6 +4,7 @@ import com.itsaky.androidide.language.BaseLanguage;
 import com.itsaky.androidide.language.java.manager.JavaCharacter;
 import com.itsaky.androidide.language.java.parser.JavaLexer;
 import com.itsaky.androidide.language.java.parser.JavaParser;
+import com.itsaky.androidide.lsp.LSPProvider;
 import com.itsaky.androidide.models.AndroidProject;
 import io.github.rosemoe.editor.interfaces.AutoCompleteProvider;
 import io.github.rosemoe.editor.interfaces.CodeAnalyzer;
@@ -13,6 +14,7 @@ import io.github.rosemoe.editor.widget.SymbolPairMatch;
 import java.io.StringReader;
 import org.antlr.v4.runtime.CharStreams;
 import org.antlr.v4.runtime.Token;
+import org.eclipse.lsp4j.services.LanguageServer;
 
 public class JavaLanguage extends BaseLanguage {
     
@@ -22,10 +24,20 @@ public class JavaLanguage extends BaseLanguage {
 
 	public JavaLanguage(AndroidProject project) {
 		this.analyzer = new JavaLanguageAnalyzer();
-		this.complete = new JavaAutoComplete(analyzer);
+		this.complete = new JavaAutoComplete(this);
 		this.project  = project;
 	}
 
+    @Override
+    public LanguageServer getLanguageServer() {
+        return LSPProvider.getServerForLanguage(LSPProvider.LANGUAGE_JAVA);
+    }
+
+    @Override
+    public String getLanguageCode() {
+        return LSPProvider.LANGUAGE_JAVA;
+    }
+
 	@Override
 	public CodeAnalyzer getAnalyzer() {
 		return analyzer;
@@ -105,19 +117,6 @@ public class JavaLanguage extends BaseLanguage {
             return new HandleResult(sb, shiftLeft);
         }
     }
-
-	public static String[] getKeywords() {
-		return new String[] {
-			"abstract", "assert", "boolean", "break", "byte", "case", 
-			"catch", "char", "class", "const", "continue", "default", 
-			"do", "double", "else", "enum", "extends", "final", "finally", 
-			"float", "for", "if", "goto", "implements", "import", "instanceof", 
-			"int", "interface", "long", "native", "new", "package", "private", 
-			"protected", "public", "return", "short", "static", "strictfp", 
-			"super", "switch", "synchronized", "this", "throw", "throws", 
-			"transient", "try", "void", "volatile", "while", "null"
-		};
-	}
     
     private class JavaSymbolPairs extends SymbolPairMatch {
         public JavaSymbolPairs() {

app/src/main/java/com/itsaky/androidide/language/logs/LogLanguageImpl.java

@@ -2,18 +2,17 @@ package com.itsaky.androidide.language.logs;
 
 import com.itsaky.androidide.language.BaseLanguage;
 import com.itsaky.androidide.models.LogLine;
-import com.itsaky.androidide.models.SuggestItem;
-import com.itsaky.androidide.utils.Either;
 import io.github.rosemoe.editor.interfaces.AutoCompleteProvider;
 import io.github.rosemoe.editor.interfaces.CodeAnalyzer;
 import io.github.rosemoe.editor.interfaces.NewlineHandler;
-import io.github.rosemoe.editor.struct.CompletionItem;
 import io.github.rosemoe.editor.text.TextAnalyzeResult;
 import io.github.rosemoe.editor.text.TextAnalyzer;
 import io.github.rosemoe.editor.widget.CodeEditor;
 import io.github.rosemoe.editor.widget.SymbolPairMatch;
 import java.util.ArrayList;
 import java.util.List;
+import org.eclipse.lsp4j.CompletionItem;
+import org.eclipse.lsp4j.services.LanguageServer;
 
 public class LogLanguageImpl extends BaseLanguage {
 	
@@ -23,6 +22,16 @@ public class LogLanguageImpl extends BaseLanguage {
 	public LogAnalyzer addLine(LogLine line) {
 		return analyzer.addLine(line);
 	}
+
+    @Override
+    public LanguageServer getLanguageServer() {
+        return null;
+    }
+
+    @Override
+    public String getLanguageCode() {
+        return null;
+    }
 	
 	@Override
 	public CodeAnalyzer getAnalyzer() {
@@ -91,8 +100,8 @@ public class LogLanguageImpl extends BaseLanguage {
 	private static class LogCompletor implements AutoCompleteProvider {
 		
 		@Override
-		public List<Either<SuggestItem, CompletionItem>> getAutoCompleteItems(CodeEditor editor, String prefix, boolean isInCodeBlock, TextAnalyzeResult colors, int line) {
-			return new ArrayList<Either<SuggestItem, CompletionItem>>();
+		public List<CompletionItem> getAutoCompleteItems(String fileUri, String prefix, boolean isInCodeBlock, TextAnalyzeResult colors, int index, int line, int column) {
+			return new ArrayList<CompletionItem>();
 		}
 	}
 }

app/src/main/java/com/itsaky/androidide/language/xml/XMLAutoComplete.java

@@ -4,16 +4,16 @@ import com.itsaky.androidide.app.StudioApp;
 import com.itsaky.androidide.language.xml.completion.XMLCompletionService;
 import com.itsaky.androidide.models.CompletionListItem;
 import com.itsaky.androidide.models.SuggestItem;
-import com.itsaky.androidide.utils.Either;
 import com.itsaky.androidide.utils.EitherOfResult;
 import io.github.rosemoe.editor.interfaces.AutoCompleteProvider;
-import io.github.rosemoe.editor.struct.CompletionItem;
 import io.github.rosemoe.editor.text.TextAnalyzeResult;
 import io.github.rosemoe.editor.widget.CodeEditor;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Comparator;
 import java.util.List;
+import org.eclipse.lsp4j.CompletionItem;
+import org.eclipse.lsp4j.jsonrpc.messages.Either;
 
 public class XMLAutoComplete implements AutoCompleteProvider {
 	
@@ -21,26 +21,20 @@ public class XMLAutoComplete implements AutoCompleteProvider {
 
 		@Override
 		public int compare(CompletionItem p1, CompletionItem p2) {
-			return ((CompletionListItem) p1).getSortText().compareTo(((CompletionListItem) p2).getSortText());
+			return p1.getSortText().compareTo(p2.getSortText());
 		}
 	};
 	
+    /**
+     * TODO: Change this to a language server implementation and remove the use of passing editor content
+     */
 	@Override
-	public List<Either<SuggestItem, CompletionItem>> getAutoCompleteItems(CodeEditor editor, String prefix, boolean isInCodeBlock, TextAnalyzeResult colors, int line) {
-		// We do not store the completion service here in this class
-		// This is because, if we modify the instance of the service in app,
-		// it'll be updated here
-		// automatically
+	public List<CompletionItem> getAutoCompleteItems(String fileUri, String prefix, boolean isInCodeBlock, TextAnalyzeResult colors, int index, int line, int column) {
 		final XMLCompletionService service = StudioApp.getInstance().getXmlCompletionService();
-		List<CompletionItem> list = new ArrayList<CompletionItem>(sort(service.complete(editor, prefix.trim())));
-		List<Either<SuggestItem, CompletionItem>> result = new ArrayList<>();
-		for(CompletionItem item : list) {
-			result.add(new EitherOfResult(null, item));
-		}
-		return result;
+		return sort(service.complete(index, line, column, prefix.toLowerCase().trim()));
 	}
 	
-	private List<CompletionListItem> sort(List<CompletionListItem> result) {
+	private List<CompletionItem> sort(List<CompletionItem> result) {
 		Collections.sort(result, RESULTS_SORTER);
 		return result;
 	}

app/src/main/java/com/itsaky/androidide/language/xml/XMLLanguage.java

@@ -3,6 +3,7 @@ package com.itsaky.androidide.language.xml;
 import com.itsaky.androidide.language.BaseLanguage;
 import com.itsaky.androidide.language.java.manager.JavaCharacter;
 import com.itsaky.androidide.language.xml.lexer.XMLLexer;
+import com.itsaky.androidide.lsp.LSPProvider;
 import io.github.rosemoe.editor.interfaces.AutoCompleteProvider;
 import io.github.rosemoe.editor.interfaces.CodeAnalyzer;
 import io.github.rosemoe.editor.interfaces.NewlineHandler;
@@ -11,6 +12,7 @@ import io.github.rosemoe.editor.widget.SymbolPairMatch;
 import java.io.StringReader;
 import org.antlr.v4.runtime.CharStreams;
 import org.antlr.v4.runtime.Token;
+import org.eclipse.lsp4j.services.LanguageServer;
 
 public class XMLLanguage extends BaseLanguage {
 
@@ -24,6 +26,16 @@ public class XMLLanguage extends BaseLanguage {
 		this.newlineHandlers = new NewlineHandler[]{new IndentHandler()};
 	}
 
+    @Override
+    public LanguageServer getLanguageServer() {
+        return null;
+    }
+
+    @Override
+    public String getLanguageCode() {
+        return LSPProvider.LANGUAGE_XML;
+    }
+    
 	@Override
 	public CodeAnalyzer getAnalyzer() {
 		return analyzer;

app/src/main/java/com/itsaky/androidide/language/xml/completion/XMLCompletionService.java

@@ -1,7 +1,6 @@
 package com.itsaky.androidide.language.xml.completion;
 
 import com.itsaky.androidide.language.xml.lexer.XMLLexer;
-import com.itsaky.androidide.models.CompletionListItem;
 import com.itsaky.androidide.utils.Environment;
 import com.itsaky.androidide.utils.FileUtil;
 import io.github.rosemoe.editor.widget.CodeEditor;
@@ -17,10 +16,13 @@ import java.util.Map;
 import java.util.Set;
 import org.antlr.v4.runtime.CharStreams;
 import org.antlr.v4.runtime.Token;
+import org.eclipse.lsp4j.CompletionItem;
 import org.jsoup.Jsoup;
 import org.jsoup.nodes.Document;
 import org.jsoup.nodes.Element;
 import org.jsoup.select.Elements;
+import org.eclipse.lsp4j.InsertTextFormat;
+import org.eclipse.lsp4j.CompletionItemKind;
 
 public class XMLCompletionService {
 	private HashMap<String, Attr> attrs;
@@ -50,11 +52,8 @@ public class XMLCompletionService {
 	}
 	
 	
-	public List<CompletionListItem> complete(CodeEditor editor, String prefix) {
-		prefix = prefix.toLowerCase(Locale.US).trim();
-		final int line = editor.getCursor().getLeftLine();
-		final int column = editor.getCursor().getLeftColumn();
-		final List<CompletionListItem> result = new ArrayList<>();
+	public List<CompletionItem> complete(int index, int line, int column, String prefix) {
+		final List<CompletionItem> result = new ArrayList<>();
 		if(prefix.startsWith("<") || prefix.startsWith("</")) {
 			boolean slash = false;
 			prefix = prefix.substring(1).trim();
@@ -63,13 +62,17 @@ public class XMLCompletionService {
 				prefix = prefix.substring(1);
 			}
 			for(String name : widgets) {
-				if(simpleName(name).toLowerCase(Locale.US).contains(prefix))
+				if(simpleName(name).toLowerCase(Locale.US).startsWith(prefix))
 					result.add(widgetNameAsCompletion(name, slash));
 			}
 			return handleResults(result);
 		} else {
-			final IsInValueScanner scanner = new IsInValueScanner(editor.getCursor().getLeft());
-			final String name = scanner.scan(editor.getText().toString());
+            /**
+             * TODO: Change to LSP
+             */
+            final String content = "";
+			final IsInValueScanner scanner = new IsInValueScanner(index);
+			final String name = scanner.scan(content);
 			if(name != null) {
 				final String attrName = name.contains(":") ? name.substring(name.indexOf(":") + 1) : name;
                 if (attrs.containsKey(attrName)) {
@@ -77,14 +80,14 @@ public class XMLCompletionService {
                     if(attr.hasPossibleValues()) {
                         Set<String> values = attr.possibleValues;
                         for(String value : values) 
-                            if(value.toLowerCase(Locale.US).contains(prefix))
+                            if(value.toLowerCase(Locale.US).startsWith(prefix))
                                 result.add(valueAsCompletion(value));
                     }
                 }
 			} else {
 				for(Map.Entry<String, Attr> entry : attrs.entrySet()) {
 					Attr attr = entry.getValue();
-					if(attr.name.toLowerCase(Locale.US).contains(prefix))
+					if(attr.name.toLowerCase(Locale.US).startsWith(prefix))
 						result.add(attrAsCompletion(attr));
 				}
 			}
@@ -92,39 +95,37 @@ public class XMLCompletionService {
 		return handleResults(result);
 	}
 
-	private CompletionListItem valueAsCompletion(String value) {
-		CompletionListItem item = new CompletionListItem();
-		item.setLabel(value)
-			.setCommit(value)
-			.setDesc("Attribute Value")
-			.setDetail(item.getDesc())
-			.setItemType("int")
-			.setType(CompletionListItem.Type.ATTRIBUTE)
-			.cursorOffset(item.getCommit().length());
+	private CompletionItem valueAsCompletion(String value) {
+		CompletionItem item = new CompletionItem();
+		item.setLabel(value);
+        item.setDetail("Attribute value");
+        item.setInsertText(value);
+        item.setInsertTextFormat(InsertTextFormat.PlainText);
+        item.setSortText("0" + value);
+        item.setKind(CompletionItemKind.Value);
 		return item;
 	}
 
-	private CompletionListItem attrAsCompletion(Attr attr) {
-		CompletionListItem item = new CompletionListItem();
-		item.setLabel(attr.name)
-			.setCommit(attr.prefix + ":" + attr.name + "=\"" + (attr.prefix.equals("android") && attr.name.equals("id") ? "@+id/\"" : "\""))
-			.setDesc("Attribute")
-			.setDetail(item.getDesc())
-			.setItemType("int")
-			.setType(CompletionListItem.Type.ATTRIBUTE)
-			.cursorOffset(item.getCommit().length() - 1);
+	private CompletionItem attrAsCompletion(Attr attr) {
+		CompletionItem item = new CompletionItem();
+        item.setLabel(attr.name);
+        item.setDetail("Attribute");
+        item.setInsertText(attr.prefix + ":" + attr.name + "=\"" + (attr.prefix.equals("android") && attr.name.equals("id") ? "@+id/\"" : "\""));
+        item.setInsertTextFormat(InsertTextFormat.PlainText);
+        item.setSortText("1" + attr.name);
+        item.setKind(CompletionItemKind.Snippet);
 		return item;
 	}
 
-	private CompletionListItem widgetNameAsCompletion(String name, boolean slash) {
-		CompletionListItem item = new CompletionListItem();
-		final String n = simpleName(name);
-		item.setLabel(n)
-			.setCommit("<" + (slash ? "/" : "") + n)
-			.setDesc(name)
-			.setDetail(item.getDesc())
-			.setItemType("  ")
-			.setType(CompletionListItem.Type.WIDGET);
+	private CompletionItem widgetNameAsCompletion(String name, boolean slash) {
+        final String n = simpleName(name);
+		CompletionItem item = new CompletionItem();
+        item.setLabel(n);
+        item.setDetail(name);
+        item.setInsertText("<" + (slash ? "/" : "") + n);
+        item.setInsertTextFormat(InsertTextFormat.PlainText);
+        item.setSortText("2" + n);
+        item.setKind(CompletionItemKind.Value);
 		return item;
 	}
 	
@@ -132,7 +133,7 @@ public class XMLCompletionService {
 		return name.substring(name.lastIndexOf(".") + 1);
 	}
 	
-	private List<CompletionListItem> handleResults(List<CompletionListItem> result) {
+	private List<CompletionItem> handleResults(List<CompletionItem> result) {
 		return result;
 	}
 	

app/src/main/java/com/itsaky/androidide/lsp/IDELanguageClient.java

@@ -0,0 +1,153 @@
+package com.itsaky.androidide.lsp;
+
+import com.blankj.utilcode.util.FileUtils;
+import com.google.gson.Gson;
+import com.itsaky.androidide.EditorActivity;
+import com.itsaky.androidide.fragments.EditorFragment;
+import com.itsaky.androidide.interfaces.EditorActivityProvider;
+import com.itsaky.androidide.utils.LSPUtils;
+import com.itsaky.androidide.utils.Logger;
+import java.io.File;
+import java.net.URI;
+import java.util.List;
+import java.util.concurrent.CompletableFuture;
+import org.eclipse.lsp4j.Location;
+import org.eclipse.lsp4j.LocationLink;
+import org.eclipse.lsp4j.Range;
+import org.eclipse.lsp4j.ShowDocumentParams;
+import org.eclipse.lsp4j.ShowDocumentResult;
+import org.eclipse.lsp4j.services.LanguageClient;
+import org.eclipse.lsp4j.services.LanguageServer;
+
+/**
+ * AndroidIDE specific implementation of the LanguageClient
+ */
+public abstract class IDELanguageClient implements LanguageClient {
+
+    protected static final Gson gson = new Gson();
+    protected static final Logger LOG = Logger.instance("IDELanguageClient");
+
+    protected EditorActivityProvider activityProvider;
+
+    private final StarterListener starterListener;
+    private final OnConnectedListener onConnectedListener;
+
+    private boolean isConnected;
+
+    public IDELanguageClient(StarterListener starterListener, OnConnectedListener onConnectedListener) {
+        this.starterListener = starterListener;
+        this.onConnectedListener = onConnectedListener;
+    }
+
+    public void setActivityProvider(EditorActivityProvider provider) {
+        this.activityProvider = provider;
+    }
+
+    /**
+     * Are we connected to the server?
+     */
+    public boolean isConnected() {
+        return isConnected;
+    }
+
+    /**
+     * Called when the LanguageServer is connected successfully
+     */
+    protected void onServerConnected(LanguageServer server) {
+        this.isConnected = true;
+        if (onConnectedListener != null)
+            onConnectedListener.onConnected(server);
+    }
+
+    /**
+     * Called when the connection to the LanguageServer was cancelled.
+     */
+    protected void onServerDisconnected() {
+        this.isConnected = false;
+    }
+
+    /**
+     * Called when the ServerSocket is started. At this point, the {@link LSPClient} waits for the server to connect. <br>
+     * This is (probably) the proper time to start your language server as ServerSocket is waiting for a client to connect.
+     */
+    protected void startServer() {
+        if (this.starterListener != null) {
+            starterListener.startServer();
+        }
+    }
+
+    protected EditorActivity activity() {
+        if (activityProvider == null) return null;
+        return activityProvider.provide();
+    }
+
+    /**
+     * Called by {@link io.github.rosemoe.editor.widget.CodeEditor CodeEditor} to show locations in EditorActivity
+     */
+    public void showLocations(List<? extends Location> locations) {
+
+    }
+
+    /**
+     * Called by {@link io.github.rosemoe.editor.widget.CodeEditor CodeEditor} to show locations in EditorActivity
+     */
+    public void showLocationLinks(List<? extends LocationLink> locations) {
+
+    }
+
+    /**
+     * Usually called by {@link io.github.rosemoe.editor.widget.CodeEditor CodeEditor} to show a specific document in EditorActivity and select the specified range
+     */
+    @Override
+    public CompletableFuture<ShowDocumentResult> showDocument(ShowDocumentParams params) {
+        ShowDocumentResult result = new ShowDocumentResult();
+        boolean success = false;
+        
+        if(params != null && params.getUri() != null && params.getSelection() != null) {
+            File file = new File(URI.create(params.getUri()));
+            if(file.exists() && file.isFile() && FileUtils.isUtf8(file)) {
+                final Range range = params.getSelection();
+                EditorFragment frag = activity().getPagerAdapter().getFrag(activity().getBinding().tabs.getSelectedTabPosition());
+                if(frag != null
+                   && frag.getFile() != null
+                   && frag.getEditor() != null
+                   && frag.getFile().getAbsolutePath().equals(file.getAbsolutePath())) {
+                    if(LSPUtils.isEqual(range.getStart(), range.getEnd())) {
+                        frag.getEditor().setSelection(range.getStart().getLine(), range.getStart().getCharacter());
+                    } else {
+                        frag.getEditor().setSelectionRegion(range.getStart().getLine(), range.getStart().getCharacter(), range.getEnd().getLine(), range.getEnd().getCharacter());
+                    }
+                } else {
+                    activity().openFileAndSelect(file, range);
+                }
+                success = true;
+            }
+        }
+        
+        result.setSuccess(success);
+        return CompletableFuture.completedFuture(result);
+    }
+
+    @Override
+    public void telemetryEvent(Object p1) {
+        LOG.info("telemetryEvent: ", gson.toJson(p1));
+    }
+
+    /**
+     * Reports connection progress
+     */
+    protected abstract void connectionReport(String message);
+
+    /**
+     * Called when there was an error connecting to server.
+     */
+    protected abstract void connectionError(Throwable th);
+
+    public static interface StarterListener {
+        void startServer();
+    }
+
+    public static interface OnConnectedListener {
+        void onConnected(LanguageServer server);
+    }
+}

app/src/main/java/com/itsaky/androidide/lsp/LSP.java

@@ -0,0 +1,221 @@
+package com.itsaky.androidide.lsp;
+
+import com.google.gson.Gson;
+import com.itsaky.androidide.app.StudioApp;
+import com.itsaky.androidide.lsp.client.java.JavaLanguageClient;
+import com.itsaky.androidide.shell.ShellServer;
+import com.itsaky.androidide.utils.Environment;
+import com.itsaky.androidide.utils.Logger;
+import java.io.File;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.CompletableFuture;
+import org.eclipse.lsp4j.ClientCapabilities;
+import org.eclipse.lsp4j.ClientInfo;
+import org.eclipse.lsp4j.GeneralClientCapabilities;
+import org.eclipse.lsp4j.InitializeParams;
+import org.eclipse.lsp4j.InitializeResult;
+import org.eclipse.lsp4j.InitializedParams;
+import org.eclipse.lsp4j.TextDocumentClientCapabilities;
+import org.eclipse.lsp4j.WindowClientCapabilities;
+import org.eclipse.lsp4j.WorkspaceClientCapabilities;
+import org.eclipse.lsp4j.WorkspaceFolder;
+import org.eclipse.lsp4j.services.LanguageServer;
+import java.util.concurrent.ExecutionException;
+import java.util.Optional;
+import org.eclipse.lsp4j.CallHierarchyCapabilities;
+import org.eclipse.lsp4j.CodeActionCapabilities;
+import org.eclipse.lsp4j.DidChangeConfigurationCapabilities;
+import org.eclipse.lsp4j.DidChangeWatchedFilesCapabilities;
+import org.eclipse.lsp4j.ExecuteCommandCapabilities;
+import org.eclipse.lsp4j.FileOperationsWorkspaceCapabilities;
+import org.eclipse.lsp4j.SemanticTokensCapabilities;
+import org.eclipse.lsp4j.SynchronizationCapabilities;
+import org.eclipse.lsp4j.ColorProviderCapabilities;
+import org.eclipse.lsp4j.CompletionCapabilities;
+import org.eclipse.lsp4j.CompletionItemCapabilities;
+import com.itsaky.androidide.interfaces.EditorActivityProvider;
+
+/**
+ * A manager class to manage Language Server Protocol implementations
+ * An initiaize request must be sent to the server only through specific nested classes.
+ * This will make sure that we map the capabilites of each language server we support.
+ */
+public class LSP {
+    
+    private static EditorActivityProvider PROVIDER;
+    private static final Logger LOG = Logger.instance("LSP");
+    
+    /**
+     * Stores information about ports at which the specified language server must be started
+     */
+    public static class Ports {
+        public static final int JAVA = 4116;
+    }
+    
+    /**
+     * Manages Java Language Server
+     */
+    public static class Java {
+        private static ShellServer mShell;
+        private static JavaLanguageClient javaClient;
+        private static LSPClientLauncher mLauncher;
+
+        /**
+         * Starts the Java Language server and the client
+         */
+        public static void start(Runnable onStarted) {
+            if (mShell != null && mLauncher != null && mLauncher.isConnected()) {
+                return;
+            }
+            javaClient = new JavaLanguageClient(() -> LSP.Java.startJLS(false), server -> storeServerInfoAndNotify(server, onStarted));
+            javaClient.setActivityProvider(LSP.PROVIDER);
+            mLauncher = new LSPClientLauncher(javaClient, Ports.JAVA);
+            mLauncher.start();
+        }
+
+        /**
+         * Sends initialize request to the Java Language Server
+         */
+        public static Optional<InitializeResult> init(String rootPath) {
+
+            final LanguageServer server = LSPProvider.getServerForLanguage(LSPProvider.LANGUAGE_JAVA);
+            if (server == null)
+                return Optional.empty();
+
+            final List<WorkspaceFolder> folders = new ArrayList<>();
+            final File file = new File(rootPath);
+            final WorkspaceFolder folder = new WorkspaceFolder();
+            
+            folder.setUri(file.toURI().toString());
+            folder.setName(file.getName().toString());
+            folders.add(folder);
+
+            InitializeParams params = new InitializeParams();
+            params.setClientInfo(LSP.getClientInfo());
+            params.setWorkspaceFolders(folders);
+            params.setCapabilities(LSP.getCapabilities());
+
+            CompletableFuture<InitializeResult> initResult = server.initialize(params);
+            try {
+                InitializeResult result = initResult.get();
+                if(result.getCapabilities() != null) {
+                    LSPProvider.setServerCapabilitesForLanguage(LSPProvider.LANGUAGE_JAVA, result.getCapabilities());
+                }
+                return Optional.of(result);
+            } catch (Throwable e) {
+                return Optional.empty();
+            }
+        }
+        
+        /**
+         * Sends a shutdown request to the java language server
+         */
+         
+        public static void shutdown() {
+            if(mLauncher != null) {
+                mLauncher.shutdown();
+            }
+        }
+        
+        /**
+         * Start JDT LS from the command line
+         */
+        private static void startJLS(boolean quiet) {
+            mShell = StudioApp.getInstance().newShell(t -> LOG.verbose(t));
+            mShell.append(String.format("java -Djls.client.port=%d -jar %s%s", Ports.JAVA, Environment.JLS_JAR.getAbsolutePath(), quiet ? /* IMPORTANT: Do not forget the leading space */ " --quiet" : ""));
+        }
+
+        /**
+         * Store the instance of Java Language Server in LSPProvider
+         */
+        private static void storeServerInfoAndNotify(LanguageServer server, Runnable startedListener) {
+            LSPProvider.setLanguageServer(LSPProvider.LANGUAGE_JAVA, server);
+            LSPProvider.setClientForLanguage(LSPProvider.LANGUAGE_JAVA, javaClient);
+            
+            if(startedListener != null)
+                startedListener.run();
+        }
+    }
+    
+    public static void setActivityProvider(EditorActivityProvider provider) {
+        PROVIDER = provider;
+    }
+    
+    /**
+     * Shuts down all known language server
+     */
+    public static void shutdownAll() {
+        // Shutdown language servers one by one
+        LSP.Java.shutdown();
+    }
+
+    /**
+     * Global LSP client information that should be passed to LanguageServer with InitializeParams
+     */
+    public static ClientInfo getClientInfo() {
+        ClientInfo info = new ClientInfo();
+        info.setName("AndroidIDE");
+        info.setVersion(com.itsaky.androidide.BuildConfig.VERSION_NAME);
+        return info;
+    }
+
+    public static ClientCapabilities getCapabilities() {
+        ClientCapabilities capabilities = new ClientCapabilities();
+        capabilities.setGeneral(LSP.getGeneralCapabilities());
+        capabilities.setTextDocument(LSP.getTextDocumentCapabilities());
+        capabilities.setWindow(LSP.getWindowCapabilities());
+        capabilities.setWorkspace(LSP.getWorkspaceCapabilities());
+        return capabilities;
+    }
+
+    private static GeneralClientCapabilities getGeneralCapabilities() {
+        GeneralClientCapabilities c = new GeneralClientCapabilities();
+        return c;
+    }
+
+    private static TextDocumentClientCapabilities getTextDocumentCapabilities() {
+        TextDocumentClientCapabilities c = new TextDocumentClientCapabilities();
+        c.setSynchronization(synchronizationCapabilities());
+        c.setColorProvider(new ColorProviderCapabilities());
+        c.setCompletion(completionCapabilities());
+        return c;
+    }
+
+    private static CompletionCapabilities completionCapabilities() {
+        CompletionCapabilities c = new CompletionCapabilities();
+        return c;
+    }
+
+    private static SynchronizationCapabilities synchronizationCapabilities() {
+        SynchronizationCapabilities c = new SynchronizationCapabilities();
+        c.setDidSave(true);
+        c.setWillSave(false);
+        c.setWillSaveWaitUntil(false);
+        return c;
+    }
+
+    private static WindowClientCapabilities getWindowCapabilities() {
+        WindowClientCapabilities c = new WindowClientCapabilities();
+        return c;
+    }
+
+    private static WorkspaceClientCapabilities getWorkspaceCapabilities() {
+        WorkspaceClientCapabilities c = new WorkspaceClientCapabilities();
+        c.setApplyEdit(true);
+        c.setConfiguration(true);
+        c.setDidChangeConfiguration(new DidChangeConfigurationCapabilities(false));
+        c.setDidChangeWatchedFiles(new DidChangeWatchedFilesCapabilities(false));
+        c.setExecuteCommand(new ExecuteCommandCapabilities(true));
+        c.setFileOperations(fileOperationsWorkspaceCapabilities());
+        return c;
+    }
+    
+    private static FileOperationsWorkspaceCapabilities fileOperationsWorkspaceCapabilities() {
+        FileOperationsWorkspaceCapabilities c = new FileOperationsWorkspaceCapabilities();
+        c.setDidCreate(true);
+        c.setDidDelete(true);
+        c.setDidRename(true);
+        return c;
+    }
+}

app/src/main/java/com/itsaky/androidide/lsp/LSPClientLauncher.java

@@ -0,0 +1,193 @@
+package com.itsaky.androidide.lsp;
+
+import com.blankj.utilcode.util.CloseUtils;
+import com.itsaky.androidide.utils.Logger;
+import java.io.Closeable;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.net.InetSocketAddress;
+import java.nio.channels.AsynchronousServerSocketChannel;
+import java.nio.channels.AsynchronousSocketChannel;
+import java.nio.channels.Channels;
+import java.util.concurrent.ArrayBlockingQueue;
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.Future;
+import org.eclipse.lsp4j.jsonrpc.Launcher;
+import org.eclipse.lsp4j.launch.LSPLauncher;
+import org.eclipse.lsp4j.services.LanguageServer;
+
+/**
+ * Launches a client for a Language server and handles connection.
+ * A callback is sent to the IDELanguageClient to tell the client to start the server if necessary.
+ */
+public class LSPClientLauncher extends Thread {
+
+    private final int PORT;
+    private Future<Void> listeningFuture;
+    private final IDELanguageClient languageClient;
+
+    private AsynchronousServerSocketChannel serverSocket;
+    private LanguageServer server;
+
+    public LSPClientLauncher(IDELanguageClient client, int port) {
+        this.languageClient = client;
+        this.PORT = port;
+
+        setDaemon(true);
+    }
+
+    /**
+     * Returns the connected LanguageServer, or {@code null}
+     *
+     * @return The LanguageServer or {@code null}
+     */
+    public LanguageServer getServer() {
+        return server;
+    }
+
+    /**
+     * Are we connected to the server?
+     */
+    public boolean isConnected() {
+        return languageClient != null && languageClient.isConnected();
+    }
+
+    @Override
+    public void run() {
+        try { 
+            languageClient.connectionReport("Starting server socket");
+            serverSocket = AsynchronousServerSocketChannel.open();
+            serverSocket.bind(new InetSocketAddress(PORT));
+            languageClient.connectionReport("Waiting for server to connect...");
+            languageClient.startServer();
+
+            final AsynchronousSocketChannel server = serverSocket.accept().get();
+            final OutputStream outWriter = new OutputStreamWrapper(Channels.newOutputStream(server));
+            final InputStream inReader   = Channels.newInputStream(server);
+            languageClient.connectionReport("Server connected. Launching client...");
+            
+            Launcher<LanguageServer> launcher = LSPLauncher.createClientLauncher(languageClient, inReader, outWriter);
+            listeningFuture = launcher.startListening();
+
+            this.server = launcher.getRemoteProxy();
+            languageClient.onServerConnected(this.server);
+            languageClient.connectionReport("Server is now listening.");
+
+            while (!(listeningFuture.isCancelled() || listeningFuture.isDone())) {
+                // Take some rest
+                sleep(50);
+            }
+            
+            // Make sure we close the server. Sockets are limited resources...
+            CloseUtils.closeIOQuietly(inReader, outWriter, server);
+            languageClient.connectionReport("Server disconnected.");
+            languageClient.onServerDisconnected();
+        } catch (Throwable th) {
+            languageClient.connectionError(th);
+        }
+    }
+
+    /**
+     * Shut down the language server
+     */
+    public void shutdown() {
+        try {
+            if (this.server != null) {
+                server.shutdown();
+                server.exit();
+            }
+            serverSocket.close();
+        } catch (Throwable th) {
+            // Ignored
+        }
+    }
+
+    /**
+     * Wraps an output stream to make sure that we don't write on UI Thread
+     * Writing to a socket's output stream is considered as network operation
+     * Trying to write to a socket on UI Thread will result in NetworkOnMainThreadExeption
+     */
+
+    private class OutputStreamWrapper extends OutputStream {
+        
+        private final AsyncWriter writer;
+        private final Thread writerThread;
+        
+        public OutputStreamWrapper(OutputStream actualStream) {
+            this.writer = new AsyncWriter(actualStream);
+            this.writerThread = new Thread(writer);
+            
+            this.writerThread.start();
+        }
+        
+        @Override
+        public void write(int p1) throws IOException {
+            // Not needed
+        }
+
+        @Override
+        public void write(byte[] b) throws IOException {
+            // Do not call super.write(b);
+            // If done, it will further call write(int)
+            this.writer.write(b);
+        }
+
+        @Override
+        public void close() throws IOException {
+            super.close();
+            this.writer.close();
+        }
+    }
+    
+    /**
+     * Actual implementation of the writer thread
+     */
+    private class AsyncWriter implements Runnable, Closeable {
+
+        private final OutputStream out;
+        private boolean closed;
+
+        private final BlockingQueue<Writable> writeQueue = new ArrayBlockingQueue<>(10);
+
+        public AsyncWriter(OutputStream out) {
+            this.out = out;
+            this.closed = false;
+        }
+
+        public void write(byte[] b) {
+            this.writeQueue.add(new Writable(b));
+        }
+
+        @Override
+        public void run() {
+            while (!closed) {
+                try {
+                    Writable data = writeQueue.take();
+                    this.out.write(data.data);
+                    this.out.flush();
+                } catch (Throwable e) {
+                    LOG.error("Error writing to LanguageServer");
+                }
+            }
+            
+            LOG.info("Writer thread stopped");
+        }
+
+        @Override
+        public void close() throws IOException {
+            this.closed = true;
+            this.out.close();
+        }
+
+        class Writable {
+            byte[] data;
+
+            public Writable(byte[] data) {
+                this.data = data;
+            }
+        }
+    }
+
+    private static final Logger LOG = Logger.instance("LSPClientLauncher");
+}

app/src/main/java/com/itsaky/androidide/lsp/LSPProvider.java

@@ -0,0 +1,84 @@
+package com.itsaky.androidide.lsp;
+
+import java.util.HashMap;
+import java.util.Map;
+import org.eclipse.lsp4j.services.LanguageServer;
+import org.eclipse.lsp4j.ServerCapabilities;
+
+/**
+ * A provider that holds references to active {@link LanguageServer}s, its capabilites and its client implementation. <br>
+ * To get language server for a specific language, just call {@link #getServerForLanguage(String)}
+ */
+public class LSPProvider {
+    
+    /**
+     * Language code for Java language
+     */
+    public static final String LANGUAGE_JAVA = "java";
+    
+    /**
+     * Language code for Kotlin language
+     */
+    public static final String LANGUAGE_KOTLIN = "kotlin";
+    
+    /**
+     * Language code for XML language
+     */
+    public static final String LANGUAGE_XML = "xml";
+    
+    /**
+     * Language code for Groovy language
+     */
+    public static final String LANGUAGE_GROOVY = "groovy";
+    
+    /**
+     * Map a reference to active language servers with its language id as a key
+     */
+    private static final Map<String, LanguageServer> serverMap = new HashMap<>();
+    
+    /**
+     * Maps a reference to the capabilities of a language server with its language id as a key
+     */
+    private static final Map<String, ServerCapabilities> capabilitiesMap = new HashMap<>();
+    
+    /**
+     * Maps a reference to the client of a language server with its language id as a key
+     */
+    private static final Map<String, IDELanguageClient> clientMap = new HashMap<>();
+    
+    static void setLanguageServer(String languageCode, LanguageServer server) {
+        serverMap.put(languageCode, server);
+    }
+    
+    static void setServerCapabilitesForLanguage(String languageCode, ServerCapabilities capabilities) {
+        capabilitiesMap.put(languageCode, capabilities);
+    }
+    
+    static void setClientForLanguage(String languageCode, IDELanguageClient client) {
+        clientMap.put(languageCode, client);
+    }
+    
+    public static Map<String, LanguageServer> getAvailableServers() {
+        return serverMap;
+    }
+    
+    public static Map<String, ServerCapabilities> getAllServerCapabilities() {
+        return capabilitiesMap;
+    }
+    
+    public static Map<String, IDELanguageClient> getAllServerClients() {
+        return clientMap;
+    }
+    
+    public static LanguageServer getServerForLanguage(String languageCode) {
+        return languageCode == null ? null : serverMap.get(languageCode);
+    }
+    
+    public static ServerCapabilities getServerCapabilitiesForLanguage(String language) {
+        return language == null ? null : capabilitiesMap.get(language);
+    }
+    
+    public static IDELanguageClient getClientForLanguage(String language) {
+        return language == null ? null : clientMap.get(language);
+    }
+}

app/src/main/java/com/itsaky/androidide/lsp/client/java/JavaLanguageClient.java

@@ -0,0 +1,117 @@
+package com.itsaky.androidide.lsp.client.java;
+
+import com.itsaky.androidide.lsp.IDELanguageClient;
+import java.util.List;
+import java.util.concurrent.CompletableFuture;
+import org.eclipse.lsp4j.ApplyWorkspaceEditParams;
+import org.eclipse.lsp4j.ApplyWorkspaceEditResponse;
+import org.eclipse.lsp4j.ConfigurationParams;
+import org.eclipse.lsp4j.LogTraceParams;
+import org.eclipse.lsp4j.MessageActionItem;
+import org.eclipse.lsp4j.MessageParams;
+import org.eclipse.lsp4j.ProgressParams;
+import org.eclipse.lsp4j.PublishDiagnosticsParams;
+import org.eclipse.lsp4j.RegistrationParams;
+import org.eclipse.lsp4j.SetTraceParams;
+import org.eclipse.lsp4j.ShowDocumentParams;
+import org.eclipse.lsp4j.ShowDocumentResult;
+import org.eclipse.lsp4j.ShowMessageRequestParams;
+import org.eclipse.lsp4j.UnregistrationParams;
+import org.eclipse.lsp4j.WorkDoneProgressCreateParams;
+import org.eclipse.lsp4j.WorkspaceFolder;
+
+public class JavaLanguageClient extends IDELanguageClient {
+    
+    public JavaLanguageClient(StarterListener starterListener, OnConnectedListener onConnectedListener) {
+        super(starterListener, onConnectedListener);
+    }
+    
+    @Override
+    protected void connectionReport(String message) {
+        LOG.info("Connection report: ", message);
+    }
+
+    @Override
+    protected void connectionError(Throwable th) {
+        LOG.info("Connection error: ", th);
+    }
+    
+    @Override
+    public CompletableFuture<ApplyWorkspaceEditResponse> applyEdit(ApplyWorkspaceEditParams p1) {
+        return null;
+    }
+
+    @Override
+    public CompletableFuture<List<Object>> configuration(ConfigurationParams p1) {
+        return null;
+    }
+
+    @Override
+    public CompletableFuture<Void> createProgress(WorkDoneProgressCreateParams p1) {
+        return null;
+    }
+
+    @Override
+    public void logMessage(MessageParams p1) {
+        LOG.info("logMessage: ", gson.toJson(p1));
+    }
+
+    @Override
+    public void logTrace(LogTraceParams p1) {
+        LOG.info("logTrace: ", gson.toJson(p1));
+    }
+
+    @Override
+    public void notifyProgress(ProgressParams p1) {
+        LOG.info("notifyProgress: ", gson.toJson(p1));
+    }
+
+    @Override
+    public void publishDiagnostics(PublishDiagnosticsParams p1) {
+    }
+
+    @Override
+    public CompletableFuture<Void> refreshCodeLenses() {
+        return null;
+    }
+
+    @Override
+    public CompletableFuture<Void> refreshSemanticTokens() {
+        return null;
+    }
+
+    @Override
+    public CompletableFuture<Void> registerCapability(RegistrationParams p1) {
+        return null;
+    }
+
+    @Override
+    public void setTrace(SetTraceParams p1) {
+        LOG.info("setTrace: ", gson.toJson(p1));
+    }
+
+    @Override
+    public CompletableFuture<ShowDocumentResult> showDocument(ShowDocumentParams p1) {
+        return null;
+    }
+
+    @Override
+    public void showMessage(MessageParams p1) {
+        LOG.info("showMessage: ", gson.toJson(p1));
+    }
+
+    @Override
+    public CompletableFuture<MessageActionItem> showMessageRequest(ShowMessageRequestParams p1) {
+        return null;
+    }
+    
+    @Override
+    public CompletableFuture<Void> unregisterCapability(UnregistrationParams p1) {
+        return null;
+    }
+
+    @Override
+    public CompletableFuture<List<WorkspaceFolder>> workspaceFolders() {
+        return null;
+    }
+}

app/src/main/java/com/itsaky/androidide/managers/ToolsManager.java

@@ -17,7 +17,7 @@ public class ToolsManager {
     
     private static PreferenceManager prefs;
     
-    public static final int JLS_VERSION = 8;
+    public static final int JLS_VERSION = 12;
     public static final int LOGSENDER_VERSION = 1;
     public static final int CLEANER_VERSION = 1;
     public static final int GRADLE_API_VERSION = 2;
@@ -62,18 +62,9 @@ public class ToolsManager {
     
     
     private static void extractJlsIfNeeded() {
-        boolean gson = false, jls = false, proto = false;
-        final List<File> files = FileUtils.listFilesInDir(Environment.JLS_HOME, true);
-        for(File f : files) {
-            gson = gson == true ? gson : f.getName().equals("gson.jar");
-            jls = jls == true ? jls : f.getName().equals("jls.jar");
-            proto = proto == true ? proto : f.getName().equals("protobuf.jar");
-        }
-
-        final boolean exists = gson && jls && proto;
         final boolean isOld = JLS_VERSION > prefs.getInt(KEY_JLS_VERSION, 0);
         
-        if(!exists || isOld) {
+        if(!Environment.JLS_JAR.exists() || isOld) {
             try {
                 extractJls();
             } catch (Throwable e) {}
@@ -81,14 +72,7 @@ public class ToolsManager {
     }
 
     private static void extractJls(){
-        final File jlsZip = new File(Environment.JLS_HOME, "jls.zip");
-        ResourceUtils.copyFileFromAssets("data/jls.zip", jlsZip.getAbsolutePath());
-        try {
-            ZipFile file = new ZipFile(jlsZip, ConstantsBridge.JLS_ZIP_PASSWORD_HASH.toCharArray());
-            file.extractAll(Environment.JLS_HOME.getAbsolutePath());
-            FileUtils.delete(jlsZip);
-            prefs.putInt(KEY_JLS_VERSION, JLS_VERSION);
-        } catch (Throwable th) {}
+        ResourceUtils.copyFileFromAssets("data/jls.jar", Environment.JLS_JAR.getAbsolutePath());
     }
     
     

app/src/main/java/com/itsaky/androidide/models/SearchResult.java

@@ -1,7 +1,7 @@
 package com.itsaky.androidide.models;
 
-import com.itsaky.lsp.Range;
 import java.io.File;
+import org.eclipse.lsp4j.Range;
 
 public class SearchResult extends Range {
     public File file;
@@ -9,8 +9,8 @@ public class SearchResult extends Range {
     public String match;
     
     public SearchResult(Range src, File file, String line, String match) {
-        this.start = src.start;
-        this.end = src.end;
+        this.setStart(src.getStart());
+        this.setEnd(src.getEnd());
         this.file = file;
         this.line = line;
         this.match = match;

app/src/main/java/com/itsaky/androidide/utils/Environment.java

@@ -35,6 +35,7 @@ public final class Environment {
     
     public static final File INIT_SCRIPT;
     public static final File PROJECT_DATA_FILE;
+    public static final File JLS_JAR;
     
 	public static final File GRADLE_HOME;
 	public static final File GRADLE_PROPS;
@@ -71,7 +72,8 @@ public final class Environment {
         IDEPROPS = new File(SYSROOT, "etc/ide-environment.properties");
         LIBHOOK = new File(LIBDIR, "libhook.so");
         PROJECT_DATA_FILE = new File(TMP_DIR, "ide_project");
-
+        JLS_JAR = new File(JLS_HOME, "jls.jar");
+        
         INIT_SCRIPT = new File(mkdirIfNotExits(new File(app.getIDEDataDir(), "init")), "androidide.init.gradle");
         BOOTCLASSPATH = new File("");
         GRADLE_USER_HOME = new File(HOME, ".gradle");

app/src/main/java/com/itsaky/androidide/utils/JSONUtility.java

@@ -0,0 +1,9 @@
+package com.itsaky.androidide.utils;
+
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+
+public class JSONUtility {
+    public static final Gson gson = new Gson();
+    public static final Gson prettyPrinter = new GsonBuilder().setPrettyPrinting().create();
+}

app/src/main/java/com/itsaky/androidide/utils/LSPUtils.java

@@ -0,0 +1,31 @@
+package com.itsaky.androidide.utils;
+
+import org.eclipse.lsp4j.Position;
+import org.eclipse.lsp4j.Range;
+
+public class LSPUtils {
+    
+    public static final Position Position_ofZero;
+    public static final Range Range_ofZero;
+    
+    static {
+        Position_ofZero = new Position(0, 0);
+        Range_ofZero = new Range(Position_ofZero, Position_ofZero);
+    }
+    
+    public static boolean isEqual(Position p1, Position p2) {
+        if(p1 == null) return false;
+        if(p2 == null) return false;
+        
+        return p1.getLine() == p2.getLine()
+            && p1.getCharacter() == p2.getCharacter();
+    }
+    
+    public static boolean isEqual(Range r1, Range r2) {
+        if(r1 == null) return false;
+        if(r2 == null) return false;
+
+        return LSPUtils.isEqual(r1.getStart(), r2.getStart())
+            && LSPUtils.isEqual(r1.getEnd(), r2.getEnd());
+    }
+}

app/src/main/java/com/itsaky/androidide/utils/RecursiveFileSearcher.java

@@ -4,19 +4,19 @@ import com.blankj.utilcode.util.FileIOUtils;
 import com.blankj.utilcode.util.FileUtils;
 import com.itsaky.androidide.models.SearchResult;
 import com.itsaky.androidide.tasks.TaskExecutor;
-import com.itsaky.lsp.Position;
-import com.itsaky.lsp.Range;
 import io.github.rosemoe.editor.text.CharPosition;
 import io.github.rosemoe.editor.text.Content;
 import java.io.File;
 import java.io.FileFilter;
 import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.Callable;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
-import java.util.HashMap;
+import org.eclipse.lsp4j.Position;
+import org.eclipse.lsp4j.Range;
 
 /**
  * This class provides API to search in files recursively
@@ -84,8 +84,8 @@ public class RecursiveFileSearcher {
                         final Range range = new Range();
                         final CharPosition start = content.getIndexer().getCharPosition(matcher.start());
                         final CharPosition end = content.getIndexer().getCharPosition(matcher.end());
-                        range.start = new Position(start.line, start.column);
-                        range.end = new Position(end.line, end.column);
+                        range.setStart(new Position(start.line, start.column));
+                        range.setEnd(new Position(end.line, end.column));
                         String sub = "...".concat(text.substring(Math.max(0, matcher.start() - 30), Math.min(matcher.end() + 31, text.length()))).trim().concat("...");
                         String match = content.subContent(start.line, start.column, end.line, end.column).toString();
                         ranges.add(new SearchResult(range, file, sub.replaceAll("\\s+", " "), match));

app/src/main/java/io/github/rosemoe/editor/interfaces/AutoCompleteProvider.java

@@ -15,12 +15,11 @@
  */
 package io.github.rosemoe.editor.interfaces;
 
-import com.itsaky.androidide.models.SuggestItem;
-import com.itsaky.androidide.utils.Either;
-import io.github.rosemoe.editor.struct.CompletionItem;
 import io.github.rosemoe.editor.text.TextAnalyzeResult;
 import io.github.rosemoe.editor.widget.CodeEditor;
 import java.util.List;
+import org.eclipse.lsp4j.CompletionItem;
+import com.itsaky.androidide.utils.Logger;
 
 /**
  * Interface for auto completion analysis
@@ -28,7 +27,7 @@ import java.util.List;
  * @author Rose
  */
 public interface AutoCompleteProvider {
-
+    
     /**
      * Analyze auto complete items
      *
@@ -38,7 +37,7 @@ public interface AutoCompleteProvider {
      * @param line          The line of cursor
      * @return Analyzed items
      */
-    List<Either<SuggestItem, CompletionItem>> getAutoCompleteItems(CodeEditor editor, String prefix, boolean isInCodeBlock, TextAnalyzeResult colors, int line);
+    List<CompletionItem> getAutoCompleteItems(String fileUri, String prefix, boolean isInCodeBlock, TextAnalyzeResult colors, int index, int line, int column) throws Exception;
 
 }
 

app/src/main/java/io/github/rosemoe/editor/interfaces/EditorLanguage.java

@@ -16,6 +16,7 @@
 package io.github.rosemoe.editor.interfaces;
 
 import io.github.rosemoe.editor.widget.SymbolPairMatch;
+import org.eclipse.lsp4j.services.LanguageServer;
 
 /**
  * Language for editor
@@ -32,7 +33,19 @@ import io.github.rosemoe.editor.widget.SymbolPairMatch;
  * @author Rose
  */
 public interface EditorLanguage {
-
+    
+    /**
+     * Get the language server for this available
+     * May return null.
+     */
+    LanguageServer getLanguageServer();
+    
+    /**
+     * Get the language code of this language.
+     * This must be the one specified in {@link com.itsaky.androidide.lsp.LSPProvider LSPProvider}
+     */
+    String getLanguageCode();
+     
     /**
      * Get CodeAnalyzer of this language object
      *

app/src/main/java/io/github/rosemoe/editor/langs/EmptyLanguage.java

@@ -15,27 +15,36 @@
  */
 package io.github.rosemoe.editor.langs;
 
-import com.itsaky.androidide.models.SuggestItem;
-import com.itsaky.androidide.utils.Either;
-import io.github.rosemoe.editor.interfaces.AutoCompleteProvider;
-import io.github.rosemoe.editor.interfaces.CodeAnalyzer;
-import io.github.rosemoe.editor.interfaces.EditorLanguage;
-import io.github.rosemoe.editor.interfaces.NewlineHandler;
-import io.github.rosemoe.editor.struct.CompletionItem;
-import io.github.rosemoe.editor.text.TextAnalyzeResult;
-import io.github.rosemoe.editor.text.TextAnalyzer.AnalyzeThread.Delegate;
-import io.github.rosemoe.editor.widget.CodeEditor;
-import io.github.rosemoe.editor.widget.SymbolPairMatch;
-import java.util.ArrayList;
-import java.util.List;
-
 /**
  * Empty language without any effect
  *
  * @author Rose
  */
+import io.github.rosemoe.editor.interfaces.AutoCompleteProvider;
+import io.github.rosemoe.editor.interfaces.CodeAnalyzer;
+import io.github.rosemoe.editor.interfaces.EditorLanguage;
+import io.github.rosemoe.editor.interfaces.NewlineHandler;
+import io.github.rosemoe.editor.text.TextAnalyzeResult;
+import io.github.rosemoe.editor.widget.CodeEditor;
+import io.github.rosemoe.editor.widget.SymbolPairMatch;
+import java.util.ArrayList;
+import java.util.List;
+import org.eclipse.lsp4j.CompletionItem;
+import org.eclipse.xtend.lib.annotations.Delegate;
+import org.eclipse.lsp4j.services.LanguageServer;
+
 public class EmptyLanguage implements EditorLanguage {
 
+    @Override
+    public LanguageServer getLanguageServer() {
+        return null;
+    }
+
+    @Override
+    public String getLanguageCode() {
+        return null;
+    }
+    
     @Override
     public CharSequence format(CharSequence text) {
         return text;
@@ -80,8 +89,8 @@ public class EmptyLanguage implements EditorLanguage {
     public static class EmptyAutoCompleteProvider implements AutoCompleteProvider {
 
         @Override
-        public List<Either<SuggestItem, CompletionItem>> getAutoCompleteItems(CodeEditor editor, String prefix, boolean isInCodeBlock, TextAnalyzeResult colors, int line) {
-            return new ArrayList<Either<SuggestItem, CompletionItem>>();
+        public List<CompletionItem> getAutoCompleteItems(String fileUri, String prefix, boolean isInCodeBlock, TextAnalyzeResult colors, int index, int line, int column) {
+            return new ArrayList<CompletionItem>();
         }
 
     }
@@ -89,10 +98,9 @@ public class EmptyLanguage implements EditorLanguage {
     private static class EmptyCodeAnalyzer implements CodeAnalyzer {
 
         @Override
-        public void analyze(CharSequence content, TextAnalyzeResult colors, Delegate delegate) {
+        public void analyze(CharSequence content, TextAnalyzeResult colors, io.github.rosemoe.editor.text.TextAnalyzer.AnalyzeThread.Delegate delegate) {
             colors.addNormalIfNull();
         }
-
     }
 }
 

app/src/main/java/io/github/rosemoe/editor/widget/CodeEditor.java

@@ -58,27 +58,21 @@ import androidx.annotation.Px;
 import androidx.appcompat.app.AppCompatActivity;
 import androidx.appcompat.view.ActionMode;
 import androidx.appcompat.view.menu.MenuBuilder;
-import com.blankj.utilcode.util.ThrowableUtils;
 import com.google.android.material.dialog.MaterialAlertDialogBuilder;
 import com.itsaky.androidide.R;
+import com.itsaky.androidide.app.StudioApp;
 import com.itsaky.androidide.databinding.LayoutDialogTextInputBinding;
 import com.itsaky.androidide.interfaces.JLSRequestor;
-import com.itsaky.androidide.managers.VersionedFileManager;
+import com.itsaky.androidide.lsp.LSPProvider;
 import com.itsaky.androidide.syntax.colorschemes.SchemeAndroidIDE;
 import com.itsaky.androidide.utils.Logger;
 import com.itsaky.androidide.utils.Symbols;
 import com.itsaky.androidide.utils.TypefaceUtils;
+import com.itsaky.lsp.CodeAction;
 import com.itsaky.lsp.Diagnostic;
 import com.itsaky.lsp.DiagnosticSeverity;
-import com.itsaky.lsp.DidChangeTextDocumentParams;
-import com.itsaky.lsp.Position;
 import com.itsaky.lsp.Range;
-import com.itsaky.lsp.ReferenceContext;
-import com.itsaky.lsp.ReferenceParams;
-import com.itsaky.lsp.TextDocumentContentChangeEvent;
-import com.itsaky.lsp.TextDocumentIdentifier;
-import com.itsaky.lsp.TextDocumentPositionParams;
-import com.itsaky.lsp.VersionedTextDocumentIdentifier;
+import com.itsaky.toaster.Toaster;
 import io.github.rosemoe.editor.interfaces.EditorEventListener;
 import io.github.rosemoe.editor.interfaces.EditorLanguage;
 import io.github.rosemoe.editor.interfaces.NewlineHandler;
@@ -106,8 +100,29 @@ import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
-import com.itsaky.lsp.CodeActionParams;
-import com.itsaky.lsp.CodeAction;
+import java.util.concurrent.CompletableFuture;
+import org.eclipse.lsp4j.DefinitionParams;
+import org.eclipse.lsp4j.DidChangeTextDocumentParams;
+import org.eclipse.lsp4j.DidCloseTextDocumentParams;
+import org.eclipse.lsp4j.DidOpenTextDocumentParams;
+import org.eclipse.lsp4j.DidSaveTextDocumentParams;
+import org.eclipse.lsp4j.Location;
+import org.eclipse.lsp4j.LocationLink;
+import org.eclipse.lsp4j.Position;
+import org.eclipse.lsp4j.ServerCapabilities;
+import org.eclipse.lsp4j.TextDocumentContentChangeEvent;
+import org.eclipse.lsp4j.TextDocumentIdentifier;
+import org.eclipse.lsp4j.TextDocumentItem;
+import org.eclipse.lsp4j.VersionedTextDocumentIdentifier;
+import org.eclipse.lsp4j.jsonrpc.messages.Either;
+import org.eclipse.lsp4j.services.LanguageServer;
+import android.app.ProgressDialog;
+import com.blankj.utilcode.util.ThreadUtils;
+import com.itsaky.androidide.lsp.IDELanguageClient;
+import org.eclipse.lsp4j.ShowDocumentParams;
+import org.eclipse.lsp4j.CodeActionOptions;
+import org.eclipse.lsp4j.DefinitionOptions;
+import org.eclipse.lsp4j.ReferenceOptions;
 
 /**
  * CodeEditor is a editor that can highlight text regions by doing basic syntax analyzing
@@ -194,6 +209,7 @@ public class CodeEditor extends View implements ContentListener, TextAnalyzer.Ca
     private int mCachedLineNumberWidth;
 	private int mErrorColor;
 	private int mWarningColor;
+    private int mFileVersion = 0;
     private float mDpUnit;
     private float mDividerWidth;
     private float mDividerMargin;
@@ -213,6 +229,9 @@ public class CodeEditor extends View implements ContentListener, TextAnalyzer.Ca
     private boolean mLineNumberEnabled;
     private boolean mBlockLineEnabled;
     private boolean mAutoCompletionEnabled;
+    private boolean mFindReferencesEnabled;
+    private boolean mGotoDefinitionEnabled;
+    private boolean mCodeActionsEnabled;
     private boolean mCompletionOnComposing;
     private boolean mHighlightSelectedText;
     private boolean mHighlightCurrentBlock;
@@ -245,6 +264,7 @@ public class CodeEditor extends View implements ContentListener, TextAnalyzer.Ca
     private EditorColorScheme mColors;
     private String mLnTip = "Line:";
     private EditorLanguage mLanguage;
+    private LanguageServer mLanguageServer;
     private long mLastMakeVisible = 0;
     private EditorAutoCompleteWindow mCompletionWindow;
     private DiagnosticWindow mDiagnosticWindow;
@@ -253,7 +273,6 @@ public class CodeEditor extends View implements ContentListener, TextAnalyzer.Ca
     private GestureDetector mBasicDetector;
     protected EditorTextActionPresenter mTextActionPresenter;
     private ScaleGestureDetector mScaleDetector;
-    EditorInputConnection mConnection;
     private CursorAnchorInfo.Builder mAnchorInfoBuilder;
     private MaterialEdgeEffect mVerticalEdgeGlow;
     private MaterialEdgeEffect mHorizontalGlow;
@@ -269,6 +288,7 @@ public class CodeEditor extends View implements ContentListener, TextAnalyzer.Ca
     private SymbolPairMatch mOverrideSymbolPairs;
     private LongArrayList mPostDrawLineNumbers = new LongArrayList();
     private CharPosition mLockedSelection;
+    EditorInputConnection mConnection;
     KeyMetaStates mKeyMetaStates = new KeyMetaStates(this);
 	
 	private Map<HexColor, Integer> mLineColors;
@@ -306,8 +326,42 @@ public class CodeEditor extends View implements ContentListener, TextAnalyzer.Ca
         return currentFile;
     }
     
+    /**
+     * Set the current file whose contents this editor is editing <br>
+     * This method must be called only once in this editors lifetime <br>
+     * This will also make sure to send 'textDocument/didOpen' to any provided language server.
+     *
+     * @param file The file that was opened
+     */
     public void setFile(File file) {
         this.currentFile = file;
+        
+        if(mLanguageServer != null) {
+            TextDocumentItem item = new TextDocumentItem();
+            item.setLanguageId(getLanguageIdForFile());
+            item.setText(getText().toString());
+            item.setUri(file.toURI().toString());
+            item.setVersion(mFileVersion = 0);
+            mLanguageServer.getTextDocumentService().didOpen(new DidOpenTextDocumentParams(item));
+        }
+    }
+    
+    private String getLanguageIdForFile() {
+        final String name = getFile().getName();
+        
+        if(name.endsWith(".java")) {
+            return "java";
+        }
+        
+        if(name.endsWith(".xml")) {
+            return "xml";
+        }
+        
+        if(name.endsWith(".kt")) {
+            return "kotlin";
+        }
+        
+        return "unknown";
     }
     
     /**
@@ -555,14 +609,14 @@ public class CodeEditor extends View implements ContentListener, TextAnalyzer.Ca
         int leftCol = getCursor().getLeftColumn();
         int rightLine = getCursor().getRightLine();
         int rightCol = getCursor().getRightColumn();
-        final Range range = new Range(new Position(leftLine, leftCol), new Position(rightLine, rightCol));
+        final org.eclipse.lsp4j. Range range = new org.eclipse.lsp4j. Range(new Position(leftLine, leftCol), new Position(rightLine, rightCol));
         final Set<Range> keys = mDiagnostics.keySet();
         Range found = null;
         for(Range r : keys) {
-            if(r.start.line <= range.start.line
-               && r.start.column <= range.start.column
-               && r.end.line >= range.end.line
-               && r.end.column >= range.end.column) {
+            if(r.start.line <= range.getStart().getLine()
+               && r.start.column <= range.getStart().getCharacter()
+               && r.end.line >= range.getEnd().getLine()
+               && r.end.column >= range.getEnd().getCharacter()) {
                 found = r;
                 break;
             }
@@ -749,7 +803,8 @@ public class CodeEditor extends View implements ContentListener, TextAnalyzer.Ca
             lang = new EmptyLanguage();
         }
         this.mLanguage = lang;
-
+        this.mLanguageServer = mLanguage.getLanguageServer();
+        
         // Update spanner
         if (mSpanner != null) {
             mSpanner.shutdown();
@@ -781,13 +836,63 @@ public class CodeEditor extends View implements ContentListener, TextAnalyzer.Ca
         if (mCursor != null) {
             mCursor.setLanguage(mLanguage);
         }
+        
+        setupLanguageServerCapabilities();
+        
         invalidate();
     }
     
     public EditorLanguage getEditorLanguage() {
         return mLanguage;
     }
-
+    
+    /**
+     * Get the {@link org.eclipse.lsp4j.services.LanguageServer current language server} which is set to this editor
+     * May return null;
+     *
+     * @return Current language server or {@code null}.
+     */
+    public LanguageServer getLanguageServer () {
+        return mLanguageServer;
+    }
+    
+    /**
+     * Sets up this editor according to the capabilities of the current language server
+     */
+    private void setupLanguageServerCapabilities() {
+        if(mLanguage == null || mLanguageServer == null) return;
+        
+        ServerCapabilities c = LSPProvider.getServerCapabilitiesForLanguage(mLanguage.getLanguageCode());
+        if(c == null) {
+            mCodeActionsEnabled = mGotoDefinitionEnabled = mFindReferencesEnabled = false;
+            return;
+        }
+        
+        Either<Boolean, CodeActionOptions> codeActionOptions = c.getCodeActionProvider();
+        if(codeActionOptions.isLeft()) {
+            mCodeActionsEnabled = codeActionOptions.getLeft();
+        } else {
+            CodeActionOptions options = codeActionOptions.getRight();
+            mCodeActionsEnabled = options != null;
+        }
+        
+        Either<Boolean, DefinitionOptions> definitionOptions = c.getDefinitionProvider();
+        if(definitionOptions.isLeft()) {
+            mGotoDefinitionEnabled = definitionOptions.getLeft();
+        } else {
+            DefinitionOptions options = definitionOptions.getRight();
+            mGotoDefinitionEnabled = options != null;
+        }
+        
+        Either<Boolean, ReferenceOptions> referenceOptions = c.getReferencesProvider();
+        if(definitionOptions.isLeft()) {
+            mFindReferencesEnabled = referenceOptions.getLeft();
+        } else {
+            ReferenceOptions options = referenceOptions.getRight();
+            mFindReferencesEnabled = options != null;
+        }
+    }
+     
     /**
      * Getter
      *
@@ -2575,6 +2680,28 @@ public class CodeEditor extends View implements ContentListener, TextAnalyzer.Ca
             mCompletionWindow.hide();
         }
     }
+    
+    /**
+     * Specify whether we should provide any code actions
+     * <p>
+     */
+    public void setCodeActionsEnabled(boolean codeActionsEnabled) {
+        mCodeActionsEnabled = codeActionsEnabled;
+    }
+    
+    /**
+     * Specify whether we should provide any 'Go to definition' support
+     */
+    public void setGotoDefinitionEnabled(boolean gotoDefinitionEnabled) {
+        mGotoDefinitionEnabled = gotoDefinitionEnabled;
+    }
+    
+    /**
+     * Specify whether we should provide any 'Find references' support
+     */
+    public void setFindReferencesEnabled(boolean findReferencesEnabled) {
+        mFindReferencesEnabled = findReferencesEnabled;
+    }
 
     /**
      * @see CodeEditor#setAutoCompletionEnabled(boolean)
@@ -2582,6 +2709,18 @@ public class CodeEditor extends View implements ContentListener, TextAnalyzer.Ca
     public boolean isAutoCompletionEnabled() {
         return mAutoCompletionEnabled;
     }
+    
+    public boolean isCodeActionsEnabled() {
+        return mCodeActionsEnabled && mLanguageServer != null;
+    }
+    
+    public boolean isGotoDefinitionEnabled() {
+        return mGotoDefinitionEnabled && mLanguageServer != null;
+    }
+    
+    public boolean isFindReferencesEnabled() {
+        return mFindReferencesEnabled && mLanguageServer != null;
+    }
 
     /**
      * Sets non-printable painting flags.
@@ -3767,8 +3906,6 @@ public class CodeEditor extends View implements ContentListener, TextAnalyzer.Ca
             mListener.onNewTextSet(this);
         }
         
-        notifyChanged();
-        
         if (mInputMethodManager != null) {
             mInputMethodManager.restartInput(this);
         }
@@ -4495,43 +4632,143 @@ public class CodeEditor extends View implements ContentListener, TextAnalyzer.Ca
     }
     
     public void findDefinition() {
-        if(jlsRequestor == null || getFile() == null) return;
+        if(!isGotoDefinitionEnabled()) return;
+        
+        final ProgressDialog pd = ProgressDialog.show(getContext(), null, getContext().getString(R.string.msg_finding_definition));
+        
         try {
-            TextDocumentPositionParams params = new TextDocumentPositionParams();
-            params.position = new Position(getCursor().getLeftLine(), getCursor().getLeftColumn());
-            params.textDocument = new TextDocumentIdentifier(getFile().toURI());
-            jlsRequestor.findDefinition(params);
+            final DefinitionParams params = new DefinitionParams();
+            params.setTextDocument(new TextDocumentIdentifier(getFile().toURI().toString()));
+            params.setPosition(getCursorAsLSPPosition());
+            final CompletableFuture<Either<List<? extends Location>, List<? extends LocationLink>>> future = mLanguageServer.getTextDocumentService().definition(params);
+            future.whenComplete((e, t) -> {
+                final Either<List<? extends Location>, List<? extends LocationLink>> either = e;
+                final Throwable th = t;
+                final IDELanguageClient client = LSPProvider.getClientForLanguage(mLanguage.getLanguageCode());
+                if(client == null || future.isCancelled() || future.isCompletedExceptionally()) {
+                    showDefinitionNotFound(pd);
+                    return;
+                }
+                
+                if(either.isLeft()) {
+                    List<? extends Location> locations = either.getLeft();
+                    if(locations == null || locations.size() <= 0) {
+                        showDefinitionNotFound(pd);
+                        return;
+                    }
+                    
+                    if(locations.size() == 1) {
+                        Location location = locations.get(0);
+                        showDocument(client, location.getUri(), location.getRange());
+                    } else {
+                        client.showLocations(locations);
+                    }
+                } else if(either.isRight()) {
+                    List<? extends LocationLink> locations = either.getRight();
+                    if(locations == null || locations.size() <= 0) {
+                        showDefinitionNotFound(pd);
+                        return;
+                    }
+                    
+                    if(locations.size() == 1) {
+                        LocationLink location = locations.get(0);
+                        showDocument(client, location.getTargetUri(), location.getTargetSelectionRange());
+                    } else {
+                        client.showLocationLinks(locations);
+                    }
+                }
+            });
         } catch (Throwable th) {
-            LOG.error(ThrowableUtils.getFullStackTrace(th));
+            showDefinitionNotFound(pd);
         }
     }
     
+    private void showDefinitionNotFound(final ProgressDialog pd) {
+        ThreadUtils.runOnUiThread(() -> {
+            toast(R.string.msg_no_definition, Toaster.Type.ERROR);
+            pd.dismiss();
+        });
+    }
+    
     public void findReferences() {
-        if(jlsRequestor == null || getFile() == null) return;
+        if(!isFindReferencesEnabled()) return;
+        
+        final ProgressDialog pd = ProgressDialog.show(getContext(), null, getContext().getString(R.string.msg_finding_definition));
+        
         try {
-            ReferenceParams params = new ReferenceParams();
-            params.context = new ReferenceContext(true);
-            params.position = new Position(getCursor().getLeftLine(), getCursor().getLeftColumn());
-            params.textDocument = new TextDocumentIdentifier(getFile().toURI());
-            jlsRequestor.findReferences(params);
+
         } catch (Throwable th) {
-            LOG.error(ThrowableUtils.getFullStackTrace(th));
+            showReferencesNotFound(pd);
         }
     }
     
-    public void performCodeActions(List<CodeAction> actions) {
-        if(jlsRequestor != null && getFile() != null) {
-            jlsRequestor.performCodeActions(getFile(), actions);
+    private void showReferencesNotFound(final ProgressDialog pd) {
+        ThreadUtils.runOnUiThread(() -> {
+            toast(R.string.msg_no_references, Toaster.Type.ERROR);
+            pd.dismiss();
+        });
+    }
+    
+    /**
+     * Request the client to show the specific document in an editor and select the provided range
+     */
+    private void showDocument(IDELanguageClient client, String uri, org.eclipse.lsp4j.Range range) {
+        ShowDocumentParams params = new ShowDocumentParams();
+        params.setExternal(false);
+        params.setSelection(range);
+        params.setUri(uri);
+        client.showDocument(params);
+    }
+    
+    public void didSave () {
+        if(mLanguageServer != null && getFile() != null) {
+            mLanguageServer.getTextDocumentService().didSave(new DidSaveTextDocumentParams(new org.eclipse.lsp4j.TextDocumentIdentifier(getFile().toURI().toString())));
         }
     }
+    
+    public void close() {
+        if(mLanguageServer != null && getFile() != null) {
+            mLanguageServer.getTextDocumentService().didClose(new DidCloseTextDocumentParams(new org.eclipse.lsp4j.TextDocumentIdentifier(getFile().toURI().toString())));
+        }
+    }
+    
+    public void codeAction() {
+        
+    }
+    
+    public Position getCursorAsLSPPosition() {
+        return new Position(getCursor().getLeftLine(), getCursor().getLeftColumn());
+    }
+    
+    private boolean isInString() {
+        final int line = getCursor().getLeftLine();
+        final int column = getCursor().getLeftColumn();
+        if(stringMap == null || stringMap.isEmpty() || !stringMap.containsKey(line)) return false;
+        List<Range> strings = stringMap.get(line);
+        if(strings == null || strings.isEmpty()) return false;
+        for(int i=0;i<strings.size();i++) {
+            Range r = strings.get(i);
+            if(r.start.column <= column && column <= r.end.column)
+                return true;
+        }
+        return false;
+    }
+    
+    private void toast(int msg, Toaster.Type type) {
+        StudioApp.getInstance().toast(msg, type);
+    }
+    
+    private void toast(String msg, Toaster.Type type) {
+        StudioApp.getInstance().toast(msg, type);
+    }
 
     @Override
     public void afterInsert(Content content, int startLine, int startColumn, int endLine, int endColumn, CharSequence insertedContent) {
+        notifyChanged();
+        
         if(mDiagnosticWindow != null)
             mDiagnosticWindow.hide();
         
-        notifyChanged();
-        
         // Update spans
         if (isSpanMapPrepared(true, endLine - startLine)) {
             if (startLine == endLine) {
@@ -4591,44 +4828,13 @@ public class CodeEditor extends View implements ContentListener, TextAnalyzer.Ca
             mListener.afterInsert(this, mText, startLine, startColumn, endLine, endColumn, insertedContent);
         }
     }
-
-    private boolean isInString() {
-        final int line = getCursor().getLeftLine();
-        final int column = getCursor().getLeftColumn();
-        if(stringMap == null || stringMap.isEmpty() || !stringMap.containsKey(line)) return false;
-        List<Range> strings = stringMap.get(line);
-        if(strings == null || strings.isEmpty()) return false;
-        for(int i=0;i<strings.size();i++) {
-            Range r = strings.get(i);
-            if(r.start.column <= column && column <= r.end.column)
-                return true;
-        }
-        return false;
-    }
-
-    private void notifyChanged() {
-        if (getFile() != null && getFile().getName().endsWith(".java") && jlsRequestor != null) {
-            TextDocumentContentChangeEvent event = new TextDocumentContentChangeEvent();
-            VersionedTextDocumentIdentifier id = new VersionedTextDocumentIdentifier();
-            DidChangeTextDocumentParams p = new DidChangeTextDocumentParams();
-            List<TextDocumentContentChangeEvent> changes = new ArrayList<>();
-            event.text = getText().toString();
-            event.range = null;
-            changes.add(event);
-            id.uri = getFile().toURI();
-            id.version = VersionedFileManager.incrementVersion(getFile());
-            p.textDocument = id;
-            p.contentChanges = changes;
-            jlsRequestor.didChange(p);
-        }
-    }
-
+    
     @Override
     public void afterDelete(Content content, int startLine, int startColumn, int endLine, int endColumn, CharSequence deletedContent) {
+        notifyChanged();
+        
         if(mDiagnosticWindow != null)
             mDiagnosticWindow.hide();
-            
-        notifyChanged();
         
         if (isSpanMapPrepared(false, endLine - startLine)) {
             if (startLine == endLine) {
@@ -4721,6 +4927,38 @@ public class CodeEditor extends View implements ContentListener, TextAnalyzer.Ca
             postInvalidate();
         }
     }
+    
+    private void notifyChanged() {
+        if(mLanguageServer != null) {
+            DidChangeTextDocumentParams p = didChangeParams();
+            if(p != null) {
+                mLanguageServer.getTextDocumentService().didChange(p);
+            }
+        }
+    }
+
+    protected DidChangeTextDocumentParams didChangeParams() {
+        if(getFile() == null) {
+            return null;
+        }
+
+        VersionedTextDocumentIdentifier doc = new VersionedTextDocumentIdentifier();
+        doc.setVersion(++mFileVersion);
+        doc.setUri(getFile().toURI().toString());
+        DidChangeTextDocumentParams p = new DidChangeTextDocumentParams();
+        p.setTextDocument(doc);
+        p.setContentChanges(createChangeEvents());
+
+        return p;
+    }
+
+    private List<TextDocumentContentChangeEvent> createChangeEvents() {
+        final List<TextDocumentContentChangeEvent> events = new ArrayList<>();
+        TextDocumentContentChangeEvent event = new TextDocumentContentChangeEvent();
+        event.setText(getText().toString());
+        events.add(event);
+        return events;
+    }
 
     public void onEndTextSelect() {
         showTextActionPopup();

app/src/main/java/io/github/rosemoe/editor/widget/DefaultCompletionItemAdapter.java

@@ -15,6 +15,11 @@
  */
 package io.github.rosemoe.editor.widget;
 
+/**
+ * Adapter to display results
+ *
+ * @author Rose
+ */
 import android.content.res.Resources;
 import android.graphics.drawable.Drawable;
 import android.util.TypedValue;
@@ -25,15 +30,8 @@ import android.widget.ImageView;
 import android.widget.TextView;
 import androidx.core.content.ContextCompat;
 import com.itsaky.androidide.R;
-import com.itsaky.androidide.models.SuggestItem;
-import com.itsaky.androidide.utils.Either;
-import io.github.rosemoe.editor.struct.CompletionItem;
+import org.eclipse.lsp4j.CompletionItem;
 
-/**
- * Adapter to display results
- *
- * @author Rose
- */
 @SuppressWarnings("CanBeFinal")
 class DefaultCompletionItemAdapter extends EditorCompletionAdapter {
 
@@ -47,29 +45,24 @@ class DefaultCompletionItemAdapter extends EditorCompletionAdapter {
         if (view == null) {
             view = LayoutInflater.from(getContext()).inflate(R.layout.default_completion_result_item, parent, false);
         }
-        Either<SuggestItem, CompletionItem> item = getItem(pos);
-		String label, desc;
-		Drawable icon;
-		if(item.isLeft()) {
-			label = item.getLeft().getName();
-			desc = item.getLeft().getDescription();
-			icon = ContextCompat.getDrawable(parent.getContext(), R.mipmap.box_red);
-		} else {
-			label = item.getRight().label;
-			desc = item.getRight().desc;
-			icon = item.getRight().icon;
-		}
-        TextView tv = (TextView) view.findViewById(R.id.result_item_label);
+        final CompletionItem item = getItem(pos);
+		final String label = item.getLabel();
+        final String desc = item.getDetail();
+        final Drawable icon = ContextCompat.getDrawable(parent.getContext(), R.mipmap.box_red);
+        
+        TextView tv = view.findViewById(R.id.result_item_label);
         tv.setText(label);
-        tv = (TextView) view.findViewById(R.id.result_item_desc);
+        tv = view.findViewById(R.id.result_item_desc);
         tv.setText(desc);
         view.setTag(pos);
+        
         if (isCurrentCursorPosition) {
             view.setBackgroundColor(0xffdddddd);
         } else {
             view.setBackgroundColor(0xffffffff);
         }
-        ImageView iv = (ImageView) view.findViewById(R.id.result_item_image);
+        
+        ImageView iv = view.findViewById(R.id.result_item_image);
         iv.setImageDrawable(icon);
         return view;
     }

app/src/main/java/io/github/rosemoe/editor/widget/EditorAutoCompleteWindow.java

@@ -15,29 +15,30 @@
  */
 package io.github.rosemoe.editor.widget;
 
+/**
+ * Auto complete window for editing code quicker
+ *
+ * @author Rose
+ */
+ 
 import android.content.Context;
 import android.graphics.drawable.GradientDrawable;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.widget.Toast;
 import com.itsaky.androidide.databinding.LayoutCompletionWindowBinding;
-import com.itsaky.androidide.models.CompletionEdit;
-import com.itsaky.androidide.models.CompletionListItem;
-import com.itsaky.androidide.models.SuggestItem;
-import com.itsaky.androidide.utils.Either;
+import com.itsaky.androidide.language.java.manager.JavaCharacter;
 import io.github.rosemoe.editor.interfaces.AutoCompleteProvider;
-import io.github.rosemoe.editor.struct.CompletionItem;
 import io.github.rosemoe.editor.text.CharPosition;
-import io.github.rosemoe.editor.text.Cursor;
+import io.github.rosemoe.editor.text.Content;
 import io.github.rosemoe.editor.text.TextAnalyzeResult;
 import java.util.ArrayList;
 import java.util.List;
+import org.eclipse.lsp4j.CompletionItem;
+import org.eclipse.lsp4j.Position;
+import org.eclipse.lsp4j.Range;
+import org.eclipse.lsp4j.TextEdit;
 
-/**
- * Auto complete window for editing code quicker
- *
- * @author Rose
- */
 public class EditorAutoCompleteWindow extends EditorBasePopupWindow {
     private final static String TIP = "Refreshing...";
     private final CodeEditor mEditor;
@@ -185,47 +186,54 @@ public class EditorAutoCompleteWindow extends EditorBasePopupWindow {
      * @param pos Index of auto complete item
      */
     public void select(int pos) {
-        Either<SuggestItem, CompletionItem> either = ((EditorCompletionAdapter) mBinding.list.getAdapter()).getItem(pos);
-		if(either != null && either.isLeft()) {
-			SuggestItem item = either.getLeft();
-			item.onSelectThis(mEditor);
-		} else if(either != null && either.isRight()) {
-			final CompletionItem item = either.getRight();
-			Cursor cursor = mEditor.getCursor();
-			if (!cursor.isSelected()) {
-				int l = 1;
-				if(mLastPrefix.endsWith("."))
-					l = 0;
-				else if(mLastPrefix.contains("."))
-					l = mLastPrefix.substring(mLastPrefix.lastIndexOf(".") + 1, mLastPrefix.length() - 1).length();
-				else l = mLastPrefix.length() - 1;
-				l++;
-				if(mLastPrefix.endsWith(".")) l--;
-				mEditor.getText().delete(cursor.getLeftLine(), cursor.getLeftColumn() - l, cursor.getLeftLine(), cursor.getLeftColumn());
-				cursor.onCommitText(item.commit);
-
-				if (item.cursorOffset != item.commit.length()) {
-					int delta = (item.commit.length() - item.cursorOffset);
-					if (delta != 0) {
-						int newSel = Math.max(mEditor.getCursor().getLeft() - delta, 0);
-						CharPosition charPosition = mEditor.getCursor().getIndexer().getCharPosition(newSel);
-						mEditor.setSelection(charPosition.line, charPosition.column);
-					}
-				}
-
-				if(item instanceof CompletionListItem && ((CompletionListItem) item).hasAdditionalEdits()) {
-					for(CompletionEdit edit : ((CompletionListItem) item).getAdditionalEdits()) {
-						if(edit.position.column == -1) {
-							int col = mEditor.getText().getColumnCount(edit.position.line);
-							edit.position.column = col;
-						}
-						mEditor.getText().insert(edit.position.line, edit.position.column, edit.insertText);
-					}
-				}
-			}
-		}
+        CompletionItem item = ((EditorCompletionAdapter) mBinding.list.getAdapter()).getItem(pos);
+        Range range = getIdentifierRange(mEditor.getCursor().getRight(), mEditor.getText());
+        String text = item.getInsertText() == null ? item.getLabel() : item.getInsertText();
+        final boolean shiftLeft = text.contains("$0");
+        final boolean atEnd = text.endsWith("$0");
+        text = text.replace("$0", "");
+        
+		mEditor.getText().delete(
+            range.getStart().getLine(),
+            range.getStart().getCharacter(),
+            range.getEnd().getLine(),
+            range.getEnd().getCharacter()
+         );
+        mEditor.getCursor().onCommitText(text);
+        
+        if(shiftLeft && !atEnd) {
+            mEditor.moveSelectionLeft();
+        }
+        
+        final List<TextEdit> edits = item.getAdditionalTextEdits();
+        if(edits != null && edits.size() > 0) {
+            for(int i=0;i<edits.size();i++) {
+                final TextEdit edit = edits.get(i);
+                if(edit == null || edit.getRange() == null || edit.getNewText() == null) continue;
+                final Position start = edit.getRange().getStart();
+                final Position end =  edit.getRange().getEnd();
+                if(start == null || end == null) continue;
+                if(start.equals(end)) {
+                    mEditor.getText().insert(start.getLine(), start.getCharacter(), edit.getNewText());
+                } else {
+                    mEditor.getText().replace(start.getLine(), start.getCharacter(), end.getLine(), end.getCharacter(), edit.getNewText());
+                }
+            }
+        }
+        
         mEditor.postHideCompletionWindow();
     }
+    
+    private Range getIdentifierRange(int end, Content content) {
+        int start = end;
+        while(start > 0 && JavaCharacter.isJavaIdentifierPart(content.charAt(start - 1))) {
+            start--;
+        }
+
+        CharPosition startPos = content.getIndexer().getCharPosition(start);
+        CharPosition endPos = content.getIndexer().getCharPosition(end);
+        return new Range(new Position(startPos.line, startPos.column), new Position(endPos.line, endPos.column));
+    }
 
     /**
      * Get prefix set
@@ -261,7 +269,7 @@ public class EditorAutoCompleteWindow extends EditorBasePopupWindow {
      * @param results     Items of analysis
      * @param requestTime The time that this thread starts
      */
-    public void displayResults(final List<Either<SuggestItem, CompletionItem>> results, long requestTime) {
+    public void displayResults(final List<CompletionItem> results, long requestTime) {
         mEditor.post(() -> {
             setLoading(false);
             if (results == null || results.isEmpty()) {
@@ -287,23 +295,29 @@ public class EditorAutoCompleteWindow extends EditorBasePopupWindow {
     private class MatchThread extends Thread {
         private final long mTime;
         private final String mPrefix;
+        private final String mFileUri;
         private final boolean mInner;
         private final TextAnalyzeResult mColors;
+        private final int mIndex;
         private final int mLine;
+        private final int mColumn;
         private final AutoCompleteProvider mLocalProvider = mProvider;
 
         public MatchThread(long requestTime, String prefix) {
             mTime = requestTime;
             mPrefix = prefix;
+            mFileUri = mEditor.getFile() != null ? mEditor.getFile().toURI().toString() : null;
             mColors = mEditor.getTextAnalyzeResult();
+            mIndex = mEditor.getCursor().getLeft();
             mLine = mEditor.getCursor().getLeftLine();
+            mColumn = mEditor.getCursor().getLeftColumn();
             mInner = (!mEditor.isHighlightCurrentBlock()) || (mEditor.getBlockIndex() != -1);
         }
 
         @Override
         public void run() {
             try {
-                displayResults(mLocalProvider.getAutoCompleteItems(mEditor, mPrefix, mInner, mColors, mLine), mTime);
+                displayResults(mLocalProvider.getAutoCompleteItems(mFileUri, mPrefix, mInner, mColors, mIndex, mLine, mColumn), mTime);
             } catch (Exception e) {
                 e.printStackTrace();
                 displayResults(new ArrayList<>(), mTime);

app/src/main/java/io/github/rosemoe/editor/widget/EditorCompletionAdapter.java

@@ -20,9 +20,8 @@ import android.view.View;
 import android.view.ViewGroup;
 import android.widget.BaseAdapter;
 import com.itsaky.androidide.models.SuggestItem;
-import com.itsaky.androidide.utils.Either;
-import io.github.rosemoe.editor.struct.CompletionItem;
 import java.util.List;
+import org.eclipse.lsp4j.CompletionItem;
 
 /**
  * A class to make custom adapter for auto-completion window
@@ -32,7 +31,7 @@ import java.util.List;
 public abstract class EditorCompletionAdapter extends BaseAdapter {
 
     private EditorAutoCompleteWindow mWindow;
-    private List<Either<SuggestItem, CompletionItem>> mItems;
+    private List<CompletionItem> mItems;
 
     public void clear() {
         if(mItems != null)
@@ -42,13 +41,13 @@ public abstract class EditorCompletionAdapter extends BaseAdapter {
     /**
      * Called by {@link EditorAutoCompleteWindow} to attach some arguments
      */
-    public void attachAttributes(EditorAutoCompleteWindow window, List<Either<SuggestItem, CompletionItem>> items) {
+    public void attachAttributes(EditorAutoCompleteWindow window, List<CompletionItem> items) {
         mWindow = window;
         mItems = items;
     }
 
     @Override
-    public Either<SuggestItem, CompletionItem> getItem(int position) {
+    public CompletionItem getItem(int position) {
         return mItems.get(position);
     }
 

app/src/main/java/io/github/rosemoe/editor/widget/EditorTextActionModeStarter.java

@@ -54,8 +54,6 @@ class EditorTextActionModeStarter implements CodeEditor.EditorTextActionPresente
         }
         mActionMode = ((AppCompatActivity) mEditor.getContext()).startSupportActionMode(new ActionMode.Callback() {
             
-            private List<CodeAction> actions;
-            
             @Override
             public boolean onCreateActionMode(ActionMode actionMode, Menu menu) {
                 mEditor.mStartedActionMode = CodeEditor.ACTION_MODE_SELECT_TEXT;
@@ -71,10 +69,7 @@ class EditorTextActionModeStarter implements CodeEditor.EditorTextActionPresente
                         android.R.attr.actionModePasteDrawable,
                 });
                 
-                // TODO: Request code actions on selection change
-                actions = null;
-                
-                if(actions != null && actions.size() > 0) {
+                if(mEditor.isCodeActionsEnabled()) {
                     menu.add(0, 8, 0, mEditor.getContext().getString(com.itsaky.androidide.R.string.msg_code_actions))
                         .setIcon(createDrawable(com.itsaky.androidide.R.drawable.ic_quickfix))
                         .setShowAsActionFlags(1);
@@ -100,13 +95,17 @@ class EditorTextActionModeStarter implements CodeEditor.EditorTextActionPresente
                         .setIcon(array.getDrawable(3));
                 }
                 
-                menu.add(0, 4, 0, mEditor.getContext().getString(com.itsaky.androidide.R.string.menu_navigate_definition))
-                    .setShowAsActionFlags(1)
-                    .setIcon(createDrawable(com.itsaky.androidide.R.drawable.ic_goto_definition));
+                if(mEditor.isGotoDefinitionEnabled()) {
+                    menu.add(0, 4, 0, mEditor.getContext().getString(com.itsaky.androidide.R.string.menu_navigate_definition))
+                        .setShowAsActionFlags(1)
+                        .setIcon(createDrawable(com.itsaky.androidide.R.drawable.ic_goto_definition));
+                }
                     
-                menu.add(0, 5, 0, mEditor.getContext().getString(com.itsaky.androidide.R.string.menu_navigate_references))
-                    .setShowAsActionFlags(1)
-                    .setIcon(createDrawable( com.itsaky.androidide.R.drawable.ic_find_references));
+                if(mEditor.isFindReferencesEnabled()) {
+                    menu.add(0, 5, 0, mEditor.getContext().getString(com.itsaky.androidide.R.string.menu_navigate_references))
+                        .setShowAsActionFlags(1)
+                        .setIcon(createDrawable( com.itsaky.androidide.R.drawable.ic_find_references));
+                }
                     
                 menu.add(0, 6, 0, mEditor.getContext().getString(com.itsaky.androidide.R.string.menu_comment_line))
                     .setShowAsActionFlags(1)
@@ -139,19 +138,25 @@ class EditorTextActionModeStarter implements CodeEditor.EditorTextActionPresente
                 final MenuItem uncomment = menu.findItem(7);
                 final MenuItem codeActions = menu.findItem(8);
                 
-                def.setEnabled(isJava).getIcon().setAlpha(isJava ? 255 : 76);
-                ref.setEnabled(isJava).getIcon().setAlpha(isJava ? 255 : 76);
                 comment.setEnabled(isJava || isXml).getIcon().setAlpha(isJava || isXml ? 255 : 76);
                 uncomment.setEnabled(isJava || isXml).getIcon().setAlpha(isJava || isXml ? 255 : 76);
                 
                 /**
-                 * CodeActions menu item may, or may not be added
+                 * Thesw menu items may, or may not be added
                  * So we need to check if its null or not
                  * before we perform any further actions
                  */
                 if(codeActions != null)
                     codeActions.setEnabled(isJava).getIcon().setAlpha(isJava ? 255 : 76);
                 
+                if(def != null) {
+                    def.setEnabled(isJava).getIcon().setAlpha(isJava ? 255 : 76);
+                }
+                
+                if(ref != null) {
+                    ref.setEnabled(isJava).getIcon().setAlpha(isJava ? 255 : 76);
+                }
+                    
                 return true;
             }
 
@@ -183,7 +188,7 @@ class EditorTextActionModeStarter implements CodeEditor.EditorTextActionPresente
                         mEditor.uncommentLine();
                         break;
                     case 8:
-                        mEditor.performCodeActions(actions);
+                        mEditor.codeAction();
                         break;
                 }
                 if(menuItem.getItemId() != 0) {

build.gradle

@@ -1,15 +1,14 @@
 buildscript {
     ext {
-		build_gradle_version = '4.0.1'
-		androidide_plugin_version = '1.0.6'
+		build_gradle_version = '7.0.1'
 	}
     project.ext {
-        compileSdk = 30
-        buildTools = "30.0.2"
+        compileSdk = 31
+        buildTools = "31.0.0"
         minSdk = 21
         targetSdk = 28
-        versionCode = 102210808
-        versionName = "1.0.2.1-alpha"
+        versionCode = 103210928
+        versionName = "1.0.3-alpha"
 		packageName = "com.itsaky.androidide"
     }
 
@@ -27,7 +26,6 @@ buildscript {
     }
     dependencies {
         classpath "com.android.tools.build:gradle:$build_gradle_version"
-		classpath "com.itsaky.androidide:gradle:$androidide_plugin_version"
 		classpath 'com.github.megatronking.stringfog:gradle-plugin:2.2.1'
 		classpath 'com.github.megatronking.stringfog:xor:1.1.0'
 		classpath 'com.google.gms:google-services:4.3.8'