org.eclipse.compare.contentmergeviewer.ITokenComparator Maven / Gradle / Ivy
/*******************************************************************************
* Copyright (c) 2000, 2011 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.compare.contentmergeviewer;
import org.eclipse.compare.rangedifferencer.IRangeComparator;
/**
* For performing a so-called "token compare" on a line of text.
* This interface extends the IRangeComparator interface
* so that it can be used by the TextMergeViewer.
*
* TextMergeViewer activates the token compare when navigating into
* a range of differing lines. At first the lines are selected as a block.
* When navigating into this block the token compare shows for every line
* the differing token by selecting them.
*
* TextMergeViewer's default token comparator works on characters separated
* by whitespace. If a different strategy is needed (for example, to use Java tokens in
* a Java-aware merge viewer), clients may create their own token
* comparators by implementing this interface (and overriding the
* TextMergeViewer.createTokenComparator factory method).
*
*
* @see TextMergeViewer
*/
public interface ITokenComparator extends IRangeComparator {
/**
* Returns the start character position of the token with the given index.
* If the index is out of range (but not negative) the character position
* behind the last character (the length of the input string) is returned.
*
* @param index index of the token for which to return the start position
* @return the start position of the token with the given index
* @throws java.lang.IndexOutOfBoundsException if index is negative
*/
int getTokenStart(int index);
/**
* Returns the character length of the token with the given index.
* If the index is out of range (but not negative) the value 0 is returned.
*
* @param index index of the token for which to return the start position
* @return the character length of the token with the given index
* @throws java.lang.IndexOutOfBoundsException if index is negative
*/
int getTokenLength(int index);
}