Performance with Immutable charsequence

Signed-off-by: azerr <azerr@redhat.com>

Author: angelozerr

org.eclipse.lemminx/src/main/java/com/thaiopensource/relaxng/pattern/CMRelaxNGDocument.java

@@ -317,6 +317,6 @@ DOMNode findNodeAt(Locator locator) {
 	private static String getTextContent(DOMElement element) {
 		int start = element.getStartTagCloseOffset() + 1;
 		int end = element.getEndTagOpenOffset();
-		return element.getOwnerDocument().getText().substring(start, end);
+		return element.getOwnerDocument().getText().subSequence(start, end).toString();
 	}
 }

org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/commons/CodeActionFactory.java

@@ -28,7 +28,6 @@
 import org.eclipse.lsp4j.Range;
 import org.eclipse.lsp4j.ResourceOperation;
 import org.eclipse.lsp4j.TextDocumentEdit;
-import org.eclipse.lsp4j.TextDocumentItem;
 import org.eclipse.lsp4j.TextEdit;
 import org.eclipse.lsp4j.VersionedTextDocumentIdentifier;
 import org.eclipse.lsp4j.WorkspaceEdit;
@@ -49,7 +48,7 @@ public class CodeActionFactory {
 	 * @param diagnostic
 	 * @return
 	 */
-	public static CodeAction remove(String title, Range range, TextDocumentItem document, Diagnostic diagnostic) {
+	public static CodeAction remove(String title, Range range, TextDocument document, Diagnostic diagnostic) {
 		return replace(title, range, "", document, diagnostic);
 	}
 
@@ -64,7 +63,7 @@ public static CodeAction remove(String title, Range range, TextDocumentItem docu
 	 *
 	 * @return the CodeAction to insert a new content at the end of the given range.
 	 */
-	public static CodeAction insert(String title, Position position, String insertText, TextDocumentItem document,
+	public static CodeAction insert(String title, Position position, String insertText, TextDocument document,
 			Diagnostic diagnostic) {
 		CodeAction insertContentAction = new CodeAction(title);
 		insertContentAction.setKind(CodeActionKind.QuickFix);
@@ -84,7 +83,7 @@ public static CodeAction insert(String title, Position position, String insertTe
 	 *
 	 * @return the text edit to insert a new content at the end of the given range.
 	 */
-	public static TextDocumentEdit insertEdit(String insertText, Position position, TextDocumentItem document) {
+	public static TextDocumentEdit insertEdit(String insertText, Position position, TextDocument document) {
 		TextEdit edit = insertEdit(insertText, position);
 		return insertEdits(document, Collections.singletonList(edit));
 	}
@@ -93,19 +92,19 @@ public static TextEdit insertEdit(String insertText, Position position) {
 		return new TextEdit(new Range(position, position), insertText);
 	}
 
-	public static TextDocumentEdit insertEdits(TextDocumentItem document, List<TextEdit> edits) {
+	public static TextDocumentEdit insertEdits(TextDocument document, List<TextEdit> edits) {
 		VersionedTextDocumentIdentifier versionedTextDocumentIdentifier = new VersionedTextDocumentIdentifier(
 				document.getUri(), document.getVersion());
 		return new TextDocumentEdit(versionedTextDocumentIdentifier, edits);
 	}
 
-	public static CodeAction replace(String title, Range range, String replaceText, TextDocumentItem document,
+	public static CodeAction replace(String title, Range range, String replaceText, TextDocument document,
 			Diagnostic diagnostic) {
 		TextEdit replace = new TextEdit(range, replaceText);
 		return replace(title, Collections.singletonList(replace), document, diagnostic);
 	}
 
-	public static CodeAction replace(String title, List<TextEdit> replace, TextDocumentItem document,
+	public static CodeAction replace(String title, List<TextEdit> replace, TextDocument document,
 			Diagnostic diagnostic) {
 
 		CodeAction insertContentAction = new CodeAction(title);
@@ -128,7 +127,7 @@ public static CodeAction replace(String title, List<TextEdit> replace, TextDocum
 	 * @param document
 	 * @return the workspace edit of a given replacement text and range.
 	 */
-	public static WorkspaceEdit getReplaceWorkspaceEdit(String replaceText, Range range, TextDocumentItem document) {
+	public static WorkspaceEdit getReplaceWorkspaceEdit(String replaceText, Range range, TextDocument document) {
 		TextEdit replace = new TextEdit(range, replaceText);
 		VersionedTextDocumentIdentifier versionedTextDocumentIdentifier = new VersionedTextDocumentIdentifier(
 				document.getUri(), document.getVersion());
@@ -137,8 +136,8 @@ public static WorkspaceEdit getReplaceWorkspaceEdit(String replaceText, Range ra
 		return new WorkspaceEdit(Collections.singletonList(Either.forLeft(textDocumentEdit)));
 	}
 
-	public static CodeAction replaceAt(String title, String replaceText, TextDocumentItem document,
-			Diagnostic diagnostic, Collection<Range> ranges) {
+	public static CodeAction replaceAt(String title, String replaceText, TextDocument document, Diagnostic diagnostic,
+			Collection<Range> ranges) {
 		CodeAction insertContentAction = new CodeAction(title);
 		insertContentAction.setKind(CodeActionKind.QuickFix);
 		insertContentAction.setDiagnostics(Arrays.asList(diagnostic));

org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/commons/ILineTracker.java

@@ -135,14 +135,14 @@ public interface ILineTracker {
 	 * @param text the substitution text
 	 * @exception BadLocationException if specified range is unknown to this tracker
 	 */
-	void replace(int offset, int length, String text) throws BadLocationException;
+	void replace(int offset, int length, CharSequence text) throws BadLocationException;
 
 	/**
 	 * Sets the tracked text to the specified text.
 	 *
 	 * @param text the new tracked text
 	 */
-	void set(String text);
+	void set(CharSequence text);
 
 	Position getPositionAt(int position) throws BadLocationException;
 

org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/commons/ListLineTracker.java

@@ -343,7 +343,7 @@ public final String getLineDelimiter(int line) throws BadLocationException {
 	 * @param offset the offset in the given text
 	 * @return the information of the first found delimiter or <code>null</code>
 	 */
-	protected DelimiterInfo nextDelimiterInfo(String text, int offset) {
+	protected DelimiterInfo nextDelimiterInfo(CharSequence text, int offset) {
 		char ch;
 		int length = text.length();
 		for (int i = offset; i < length; i++) {
@@ -389,7 +389,7 @@ protected DelimiterInfo nextDelimiterInfo(String text, int offset) {
 	 * @param offset         the offset of all newly created lines
 	 * @return the number of newly created lines
 	 */
-	private int createLines(String text, int insertPosition, int offset) {
+	private int createLines(CharSequence text, int insertPosition, int offset) {
 
 		int count = 0;
 		int start = 0;
@@ -427,12 +427,12 @@ private int createLines(String text, int insertPosition, int offset) {
 	}
 
 	@Override
-	public final void replace(int position, int length, String text) throws BadLocationException {
+	public final void replace(int position, int length, CharSequence text) throws BadLocationException {
 		throw new UnsupportedOperationException();
 	}
 
 	@Override
-	public final void set(String text) {
+	public final void set(CharSequence text) {
 		fLines.clear();
 		if (text != null) {
 			fTextLength = text.length();

org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/commons/ModelTextDocument.java

@@ -97,12 +97,12 @@ private synchronized T getSynchronizedModel() {
 		return model;
 	}
 
-	@Override
+	/*@Override
 	public void setText(String text) {
 		super.setText(text);
 		// text changed, cancel the completable future which load the model
 		cancelModel();
-	}
+	}*/
 
 	@Override
 	public void setVersion(int version) {

org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/commons/TextDocument.java

@@ -17,20 +17,50 @@
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
+import org.eclipse.lemminx.commons.text.CompositeCharSequence;
+import org.eclipse.lemminx.commons.text.ImmutableCharSequence;
+import org.eclipse.lemminx.commons.text.ImmutableCharSequenceImpl;
 import org.eclipse.lsp4j.Position;
 import org.eclipse.lsp4j.Range;
 import org.eclipse.lsp4j.TextDocumentContentChangeEvent;
 import org.eclipse.lsp4j.TextDocumentItem;
+import org.eclipse.lsp4j.jsonrpc.util.Preconditions;
+import org.eclipse.lsp4j.jsonrpc.validation.NonNull;
 
 /**
  * Text document extends LSP4j {@link TextDocumentItem} to provide methods to
  * retrieve position.
  *
  */
-public class TextDocument extends TextDocumentItem {
+public class TextDocument {
 
 	private static final Logger LOGGER = Logger.getLogger(TextDocument.class.getName());
 
+	/**
+	 * The text document's uri.
+	 */
+	@NonNull
+	private String uri;
+
+	/**
+	 * The text document's language identifier
+	 */
+	@NonNull
+	private String languageId;
+
+	/**
+	 * The version number of this document (it will strictly increase after each
+	 * change, including undo/redo).
+	 */
+	private int version;
+
+	/**
+	 * The content of the opened text document.
+	 */
+	// CharSequence-based text storage for memory-efficient incremental updates
+	@NonNull
+	private ImmutableCharSequence text;
+
 	private final Object lock = new Object();
 
 	private static String DEFAULT_DELIMTER = System.lineSeparator();
@@ -41,13 +71,13 @@ public class TextDocument extends TextDocumentItem {
 
 	public TextDocument(TextDocumentItem document) {
 		this(document.getText(), document.getUri());
-		super.setVersion(document.getVersion());
-		super.setLanguageId(document.getLanguageId());
+		this.setVersion(document.getVersion());
+		this.setLanguageId(document.getLanguageId());
 	}
 
 	public TextDocument(String text, String uri) {
-		super.setUri(uri);
-		super.setText(text);
+		this.setUri(uri);
+		this.text = ImmutableCharSequenceImpl.fromString(text);
 	}
 
 	public void setIncremental(boolean incremental) {
@@ -74,8 +104,8 @@ public int offsetAt(Position position) throws BadLocationException {
 	public String lineText(int lineNumber) throws BadLocationException {
 		ILineTracker lineTracker = getLineTracker();
 		Line line = lineTracker.getLineInformation(lineNumber);
-		String text = super.getText();
-		return text.substring(line.offset, line.offset + line.length);
+		CharSequence text = getText();
+		return text.subSequence(line.offset, line.offset + line.length).toString();
 	}
 
 	public int lineOffsetAt(int position) throws BadLocationException {
@@ -115,8 +145,8 @@ public Range getWordRangeAt(int textOffset, Pattern wordDefinition) {
 			Position pos = positionAt(textOffset);
 			ILineTracker lineTracker = getLineTracker();
 			Line line = lineTracker.getLineInformation(pos.getLine());
-			String text = super.getText();
-			String lineText = text.substring(line.offset, textOffset);
+			CharSequence text = getText();
+			String lineText = text.subSequence(line.offset, textOffset).toString();
 			int position = lineText.length();
 			Matcher m = wordDefinition.matcher(lineText);
 			int currentPosition = 0;
@@ -149,7 +179,7 @@ private synchronized ILineTracker createLineTracker() {
 			return lineTracker;
 		}
 		ILineTracker lineTracker = isIncremental() ? new TreeLineTracker(new ListLineTracker()) : new ListLineTracker();
-		lineTracker.set(super.getText());
+		lineTracker.set(getText());
 		return lineTracker;
 	}
 
@@ -168,31 +198,48 @@ public void update(List<TextDocumentContentChangeEvent> changes) {
 			try {
 				long start = System.currentTimeMillis();
 				synchronized (lock) {
-					// Initialize buffer and line tracker from the current text document
-					StringBuilder buffer = new StringBuilder(getText());
+					// Get current text as CharSequence (no copy)
+					CharSequence currentText = getText();
 
 					// Loop for each changes and update the buffer
 					for (int i = 0; i < changes.size(); i++) {
 
 						TextDocumentContentChangeEvent changeEvent = changes.get(i);
 						Range range = changeEvent.getRange();
-						int length = 0;
 
 						if (range != null) {
 							Integer rangeLength = changeEvent.getRangeLength();
-							length = rangeLength != null ? rangeLength.intValue() : offsetAt(range.getEnd()) - offsetAt(range.getStart());
+							int startOffset = offsetAt(range.getStart());
+							int length;
+							
+							if (rangeLength != null) {
+								// Use rangeLength if provided (preferred)
+								length = rangeLength.intValue();
+							} else {
+								// Calculate length from range.end
+								int endOffset = offsetAt(range.getEnd());
+								length = endOffset - startOffset;
+							}
+
+							String text = changeEvent.getText();
+
+							// Use CompositeCharSequence for zero-copy update
+							// This avoids copying the entire document text
+							ImmutableCharSequence newText = CompositeCharSequence.replaceRange(currentText, startOffset,
+									startOffset + length, ImmutableCharSequenceImpl.fromString(text));
+
+							lineTracker.replace(startOffset, length, text);
+							setText(newText);
+							
+							// IMPORTANT: Update currentText for next iteration
+							currentText = newText;
 						} else {
-							// range is optional and if not given, the whole file content is replaced
-							length = buffer.length();
-							range = new Range(positionAt(0), positionAt(length));
+							// Full replacement
+							setText(changeEvent.getText());
+							lineTracker.set(changeEvent.getText());
+							currentText = getText();
 						}
-						String text = changeEvent.getText();
-						int startOffset = offsetAt(range.getStart());
-						buffer.replace(startOffset, startOffset + length, text);
-						lineTracker.replace(startOffset, length, text);
 					}
-					// Update the new text content from the updated buffer
-					setText(buffer.toString());
 				}
 				LOGGER.fine("Text document content updated in " + (System.currentTimeMillis() - start) + "ms");
 			} catch (BadLocationException e) {
@@ -209,4 +256,76 @@ public void update(List<TextDocumentContentChangeEvent> changes) {
 			}
 		}
 	}
+
+	/**
+	 * Set the text content from a String. Converts to ImmutableCharSequence
+	 * internally.
+	 * 
+	 * @param text the new text content
+	 */
+	private void setText(String text) {
+		this.text = ImmutableCharSequenceImpl.fromString(text);
+	}
+
+	private void setText(ImmutableCharSequence text) {
+		this.text = text;
+	}
+
+	public int getTextLength() {
+		return getText().length();
+	}
+
+	/**
+	 * The text document's uri.
+	 */
+	@NonNull
+	public String getUri() {
+		return this.uri;
+	}
+
+	/**
+	 * The text document's uri.
+	 */
+	public void setUri(@NonNull final String uri) {
+		this.uri = Preconditions.checkNotNull(uri, "uri");
+	}
+
+	/**
+	 * The text document's language identifier
+	 */
+	@NonNull
+	public String getLanguageId() {
+		return this.languageId;
+	}
+
+	/**
+	 * The text document's language identifier
+	 */
+	public void setLanguageId(@NonNull final String languageId) {
+		this.languageId = Preconditions.checkNotNull(languageId, "languageId");
+	}
+
+	/**
+	 * The version number of this document (it will strictly increase after each
+	 * change, including undo/redo).
+	 */
+	public int getVersion() {
+		return this.version;
+	}
+
+	/**
+	 * The version number of this document (it will strictly increase after each
+	 * change, including undo/redo).
+	 */
+	public void setVersion(final int version) {
+		this.version = version;
+	}
+
+	/**
+	 * The content of the opened text document.
+	 */
+	public CharSequence getText() {
+		return text;
+	}
+
 }