/* | |
* (c) Copyright IBM Corp. 2000, 2001. | |
* All Rights Reserved. | |
*/ | |
package org.eclipse.compare.rangedifferencer; | |
/** | |
* For breaking an object to compare into a sequence of comparable entities. | |
* <p> | |
* It is used by <code>RangeDifferencer</code> to find longest sequences of | |
* matching and non-matching ranges. | |
* <p> | |
* For example, to compare two text documents and find longest common sequences | |
* of matching and non-matching lines, the implementation must break the document | |
* into lines. <code>getRangeCount</code> would return the number of lines in the | |
* document, and <code>rangesEqual</code> would compare a specified line given | |
* with one in another <code>IRangeComparator</code>. | |
* </p> | |
* <p> | |
* Clients should implement this interface; there is no standard implementation. | |
* </p> | |
*/ | |
public interface IRangeComparator { | |
/** | |
* Returns the number of comparable entities. | |
* | |
* @return the number of comparable entities | |
*/ | |
int getRangeCount(); | |
/** | |
* Returns whether the comparable entity given by the first index | |
* matches an entity specified by the other <code>IRangeComparator</code> and index. | |
* | |
* @param thisIndex the index of the comparable entity within this <code>IRangeComparator</code> | |
* @param other the IRangeComparator to compare this with | |
* @param otherIndex the index of the comparable entity within the other <code>IRangeComparator</code> | |
* @return <code>true</code> if the comparable entities are equal | |
*/ | |
boolean rangesEqual(int thisIndex, IRangeComparator other, int otherIndex); | |
/** | |
* Returns whether a comparison should be skipped because it would be too costly (or lengthy). | |
* | |
* @param length a number on which to base the decision whether to return | |
* <code>true</code> or <code>false</code> | |
* @param maxLength another number on which to base the decision whether to return | |
* <code>true</code> or <code>false</code> | |
* @param other the other <code>IRangeComparator</code> to compare with | |
* @return <code>true</code> to avoid a too lengthy range comparison | |
*/ | |
boolean skipRangeComparison(int length, int maxLength, IRangeComparator other); | |
} |