/*******************************************************************************
* Copyright (c) 2012-2015 Codenvy, S.A.
* 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:
* Codenvy, S.A. - initial API and implementation
*******************************************************************************/
package org.eclipse.che.ide.ext.java.worker;
import org.eclipse.che.ide.api.text.BadLocationException;
import org.eclipse.che.ide.ext.java.jdt.text.AbstractDocument;
import org.eclipse.che.ide.ext.java.jdt.text.ConfigurableLineTracker;
import org.eclipse.che.ide.ext.java.jdt.text.CopyOnWriteTextStore;
import org.eclipse.che.ide.ext.java.jdt.text.GapTextStore;
/**
* Default document implementation. Uses a {@link CopyOnWriteTextStore} as text store.
* <p>
* The used line tracker considers the following strings as line delimiters: "\n", "\r", "\r\n". In case of a text replacement
* across line delimiter boundaries and with different line delimiters, the line tracker might have to be repaired. Use
* {@link #isLineInformationRepairNeeded(int, int, String)} before doing the text replace if you have the need to discover such a
* situation.
* </p>
* <p>
* The document is ready to use. It has a default position category for which a default position updater is installed.
* </p>
* <p>
* <strong>Performance:</strong> The implementation should perform reasonably well for typical source code documents. It is not
* designed for very large documents of a size of several megabytes. Space-saving implementations are initially used for both the
* text store and the line tracker; the first modification after a {@link #set(String) set} incurs the cost to transform the
* document structures to efficiently handle updates.
* </p>
* <p>
* See {@link org.eclipse.che.ide.ext.java.jdt.text.GapTextStore} and <code>TreeLineTracker</code> for algorithmic behavior of the used document structures.
* </p>
*/
public class WorkerDocument extends AbstractDocument {
private static final String[] delimeters = {"\n"};
/** Creates a new empty document. */
public WorkerDocument() {
super();
ConfigurableLineTracker lineTracker = new ConfigurableLineTracker(delimeters);
setTextStore(new CopyOnWriteTextStore(new GapTextStore()));
setLineTracker(lineTracker);
completeInitialization();
}
/**
* Creates a new document with the given initial content.
*
* @param initialContent
* the document's initial content
*/
public WorkerDocument(String initialContent) {
super();
ConfigurableLineTracker lineTracker = new ConfigurableLineTracker(delimeters);
setTextStore(new CopyOnWriteTextStore(new GapTextStore()));
setLineTracker(lineTracker);
getStore().set(initialContent);
getTracker().set(initialContent);
completeInitialization();
}
/*
* @see org.eclipse.jface.text.IRepairableDocumentExtension# isLineInformationRepairNeeded(int, int, java.lang.String)
* @since 3.4
*/
public boolean isLineInformationRepairNeeded(int offset, int length, String text) throws BadLocationException {
if ((0 > offset) || (0 > length) || (offset + length > getLength()))
throw new BadLocationException();
return isLineInformationRepairNeeded(text) || isLineInformationRepairNeeded(get(offset, length));
}
/**
* Checks whether the line information needs to be repaired.
*
* @param text
* the text to check
* @return <code>true</code> if the line information must be repaired
* @since 3.4
*/
private boolean isLineInformationRepairNeeded(String text) {
if (text == null)
return false;
int length = text.length();
if (length == 0)
return false;
int rIndex = text.indexOf('\r');
int nIndex = text.indexOf('\n');
if (rIndex == -1 && nIndex == -1)
return false;
if (rIndex > 0 && rIndex < length - 1 && nIndex > 1 && rIndex < length - 2)
return false;
String defaultLD = null;
try {
defaultLD = getLineDelimiter(0);
} catch (BadLocationException x) {
return true;
}
if (defaultLD == null)
return false;
defaultLD = getDefaultLineDelimiter();
if (defaultLD.length() == 1) {
if (rIndex != -1 && !"\r".equals(defaultLD)) //$NON-NLS-1$
return true;
if (nIndex != -1 && !"\n".equals(defaultLD)) //$NON-NLS-1$
return true;
} else if (defaultLD.length() == 2)
return rIndex == -1 || nIndex - rIndex != 1;
return false;
}
}