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Diffstat (limited to 'org.eclipse.text/src/org/eclipse/text/undo/UndoableTextChange.java')
| -rw-r--r-- | org.eclipse.text/src/org/eclipse/text/undo/UndoableTextChange.java | 381 |
1 files changed, 0 insertions, 381 deletions
diff --git a/org.eclipse.text/src/org/eclipse/text/undo/UndoableTextChange.java b/org.eclipse.text/src/org/eclipse/text/undo/UndoableTextChange.java deleted file mode 100644 index 21574aa1c42..00000000000 --- a/org.eclipse.text/src/org/eclipse/text/undo/UndoableTextChange.java +++ /dev/null @@ -1,381 +0,0 @@ -/******************************************************************************* - * Copyright (c) 2006 IBM Corporation and others. - * All rights reserved. This program and the accompanying materials - * are made available under the terms of the Eclipse Public License v1.0 - * which accompanies this distribution, and is available at - * http://www.eclipse.org/legal/epl-v10.html - * - * Contributors: - * IBM Corporation - initial API and implementation - *******************************************************************************/ -package org.eclipse.text.undo; - -import org.eclipse.core.commands.operations.AbstractOperation; -import org.eclipse.core.commands.operations.IOperationHistory; - -import org.eclipse.core.runtime.IAdaptable; -import org.eclipse.core.runtime.IProgressMonitor; -import org.eclipse.core.runtime.IStatus; -import org.eclipse.core.runtime.Status; - -import org.eclipse.jface.text.BadLocationException; -import org.eclipse.jface.text.IDocumentExtension4; - -/** - * Represents an undo-able text change, described as the - * replacement of some preserved text with new text. - * <p> - * Based on the DefaultUndoManager.TextCommand from R3.1. - * </p> - * - * @see org.eclipse.text.undo.DocumentUndoManager - * @since 3.2 - */ -class UndoableTextChange extends AbstractOperation { - - /** The start index of the replaced text. */ - protected int fStart= -1; - - /** The end index of the replaced text. */ - protected int fEnd= -1; - - /** The newly inserted text. */ - protected String fText; - - /** The replaced text. */ - protected String fPreservedText; - - /** The undo modification stamp. */ - protected long fUndoModificationStamp= IDocumentExtension4.UNKNOWN_MODIFICATION_STAMP; - - /** The redo modification stamp. */ - protected long fRedoModificationStamp= IDocumentExtension4.UNKNOWN_MODIFICATION_STAMP; - - /** The undo manager that generated the change. */ - protected DocumentUndoManager manager; - - /** - * Creates a new text change. - * - * @param manager the undo manager for this change - */ - UndoableTextChange(DocumentUndoManager manager) { - super(UndoMessages.getString("DocumentUndoManager.operationLabel")); //$NON-NLS-1$ - this.manager= manager; - addContext(manager.getUndoContext()); - } - - /** - * Re-initializes this text change. - */ - protected void reinitialize() { - fStart= fEnd= -1; - fText= fPreservedText= null; - fUndoModificationStamp= IDocumentExtension4.UNKNOWN_MODIFICATION_STAMP; - fRedoModificationStamp= IDocumentExtension4.UNKNOWN_MODIFICATION_STAMP; - } - - /** - * Sets the start and the end index of this change. - * - * @param start the start index - * @param end the end index - */ - protected void set(int start, int end) { - fStart= start; - fEnd= end; - fText= null; - fPreservedText= null; - } - - /* - * @see org.eclipse.core.commands.operations.IUndoableOperation#dispose() - */ - public void dispose() { - reinitialize(); - } - - /** - * Undo the change described by this change. - */ - protected void undoTextChange() { - try { - if (manager.fDocument instanceof IDocumentExtension4) - ((IDocumentExtension4) manager.fDocument).replace(fStart, fText - .length(), fPreservedText, fUndoModificationStamp); - else - manager.fDocument.replace(fStart, fText.length(), - fPreservedText); - } catch (BadLocationException x) { - } - } - - /* - * @see org.eclipse.core.commands.operations.IUndoableOperation#canUndo() - */ - public boolean canUndo() { - if (isValid()) { - if (manager.fDocument instanceof IDocumentExtension4) { - long docStamp= ((IDocumentExtension4) manager.fDocument) - .getModificationStamp(); - - // Normal case: an undo is valid if its redo will restore - // document to its current modification stamp - boolean canUndo= docStamp == IDocumentExtension4.UNKNOWN_MODIFICATION_STAMP - || docStamp == getRedoModificationStamp(); - - /* - * Special case to check if the answer is false. If the last - * document change was empty, then the document's modification - * stamp was incremented but nothing was committed. The - * operation being queried has an older stamp. In this case - * only, the comparison is different. A sequence of document - * changes that include an empty change is handled correctly - * when a valid commit follows the empty change, but when - * #canUndo() is queried just after an empty change, we must - * special case the check. The check is very specific to prevent - * false positives. see - * https://bugs.eclipse.org/bugs/show_bug.cgi?id=98245 - */ - if (!canUndo - && this == manager.fHistory - .getUndoOperation(manager.fUndoContext) - // this is the latest operation - && this != manager.fCurrent - // there is a more current operation not on the stack - && !manager.fCurrent.isValid() - // the current operation is not a valid document - // modification - && manager.fCurrent.fUndoModificationStamp != - // the invalid current operation has a document stamp - IDocumentExtension4.UNKNOWN_MODIFICATION_STAMP) { - canUndo= manager.fCurrent.fRedoModificationStamp == docStamp; - } - /* - * When the composite is the current operation, it may hold the - * timestamp of a no-op change. We check this here rather than - * in an override of canUndo() in UndoableCompoundTextChange simply to - * keep all the special case checks in one place. - */ - if (!canUndo - && this == manager.fHistory - .getUndoOperation(manager.fUndoContext) - && // this is the latest operation - this instanceof UndoableCompoundTextChange - && this == manager.fCurrent - && // this is the current operation - this.fStart == -1 - && // the current operation text is not valid - manager.fCurrent.fRedoModificationStamp != IDocumentExtension4.UNKNOWN_MODIFICATION_STAMP) { - // but it has a redo stamp - canUndo= manager.fCurrent.fRedoModificationStamp == docStamp; - } - - } - // if there is no timestamp to check, simply return true per the - // 3.0.1 behavior - return true; - } - return false; - } - - /* - * @see org.eclipse.core.commands.operations.IUndoableOperation#canRedo() - */ - public boolean canRedo() { - if (isValid()) { - if (manager.fDocument instanceof IDocumentExtension4) { - long docStamp= ((IDocumentExtension4) manager.fDocument) - .getModificationStamp(); - return docStamp == IDocumentExtension4.UNKNOWN_MODIFICATION_STAMP - || docStamp == getUndoModificationStamp(); - } - // if there is no timestamp to check, simply return true per the - // 3.0.1 behavior - return true; - } - return false; - } - - /* - * @see org.eclipse.core.commands.operations.IUndoableOperation#canExecute() - */ - public boolean canExecute() { - return manager.isConnected(); - } - - /* - * @see org.eclipse.core.commands.operations.IUndoableOperation.IUndoableOperation#execute(IProgressMonitor, IAdaptable) - */ - public IStatus execute(IProgressMonitor monitor, IAdaptable uiInfo) { - // Text changes execute as they are typed, so executing one has no - // effect. - return Status.OK_STATUS; - } - - /** - * {@inheritDoc} - * Notifies clients about the undo. - */ - public IStatus undo(IProgressMonitor monitor, IAdaptable uiInfo) { - if (isValid()) { - manager.fireDocumentUndo(fStart, fPreservedText, fText, uiInfo, DocumentUndoEvent.ABOUT_TO_UNDO, false); - undoTextChange(); - manager.fireDocumentUndo(fStart, fPreservedText, fText, uiInfo, DocumentUndoEvent.UNDONE, false); - return Status.OK_STATUS; - } - return IOperationHistory.OPERATION_INVALID_STATUS; - } - - /** - * Re-applies the change described by this change. - */ - protected void redoTextChange() { - try { - if (manager.fDocument instanceof IDocumentExtension4) - ((IDocumentExtension4) manager.fDocument).replace(fStart, fEnd - fStart, fText, fRedoModificationStamp); - else - manager.fDocument.replace(fStart, fEnd - fStart, fText); - } catch (BadLocationException x) { - } - } - - /** - * Re-applies the change described by this change that was previously - * undone. Also notifies clients about the redo. - * - * @param monitor the progress monitor to use if necessary - * @param uiInfo an adaptable that can provide UI info if needed - * @return the status - */ - public IStatus redo(IProgressMonitor monitor, IAdaptable uiInfo) { - if (isValid()) { - manager.fireDocumentUndo(fStart, fText, fPreservedText, uiInfo, DocumentUndoEvent.ABOUT_TO_REDO, false); - redoTextChange(); - manager.fireDocumentUndo(fStart, fText, fPreservedText, uiInfo, DocumentUndoEvent.REDONE, false); - return Status.OK_STATUS; - } - return IOperationHistory.OPERATION_INVALID_STATUS; - } - - /** - * Update the change in response to a commit. - */ - - protected void updateTextChange() { - fText= manager.fTextBuffer.toString(); - manager.fTextBuffer.setLength(0); - fPreservedText= manager.fPreservedTextBuffer.toString(); - manager.fPreservedTextBuffer.setLength(0); - } - - /** - * Creates a new uncommitted text change depending on whether a compound - * change is currently being executed. - * - * @return a new, uncommitted text change or a compound text change - */ - protected UndoableTextChange createCurrent() { - if (manager.fFoldingIntoCompoundChange) - return new UndoableCompoundTextChange(manager); - return new UndoableTextChange(manager); - } - - /** - * Commits the current change into this one. - */ - protected void commit() { - if (fStart < 0) { - if (manager.fFoldingIntoCompoundChange) { - manager.fCurrent= createCurrent(); - } else { - reinitialize(); - } - } else { - updateTextChange(); - manager.fCurrent= createCurrent(); - } - } - - /** - * Updates the text from the buffers without resetting the buffers or adding - * anything to the stack. - */ - protected void pretendCommit() { - if (fStart > -1) { - fText= manager.fTextBuffer.toString(); - fPreservedText= manager.fPreservedTextBuffer.toString(); - } - } - - /** - * Attempt a commit of this change and answer true if a new fCurrent was - * created as a result of the commit. - * - * @return <code>true</code> if the change was committed and created - * a new <code>fCurrent</code>, <code>false</code> if not - */ - protected boolean attemptCommit() { - pretendCommit(); - if (isValid()) { - manager.commit(); - return true; - } - return false; - } - - /** - * Checks whether this text change is valid for undo or redo. - * - * @return <code>true</code> if the change is valid for undo or redo - */ - protected boolean isValid() { - return fStart > -1 && fEnd > -1 && fText != null; - } - - /* - * @see java.lang.Object#toString() - */ - public String toString() { - String delimiter= ", "; //$NON-NLS-1$ - StringBuffer text= new StringBuffer(super.toString()); - text.append("\n"); //$NON-NLS-1$ - text.append(this.getClass().getName()); - text.append(" undo modification stamp: "); //$NON-NLS-1$ - text.append(fUndoModificationStamp); - text.append(" redo modification stamp: "); //$NON-NLS-1$ - text.append(fRedoModificationStamp); - text.append(" start: "); //$NON-NLS-1$ - text.append(fStart); - text.append(delimiter); - text.append("end: "); //$NON-NLS-1$ - text.append(fEnd); - text.append(delimiter); - text.append("text: '"); //$NON-NLS-1$ - text.append(fText); - text.append('\''); - text.append(delimiter); - text.append("preservedText: '"); //$NON-NLS-1$ - text.append(fPreservedText); - text.append('\''); - return text.toString(); - } - - /** - * Return the undo modification stamp - * - * @return the undo modification stamp for this change - */ - protected long getUndoModificationStamp() { - return fUndoModificationStamp; - } - - /** - * Return the redo modification stamp - * - * @return the redo modification stamp for this change - */ - protected long getRedoModificationStamp() { - return fRedoModificationStamp; - } -} |