/*******************************************************************************
* Copyright (c) 2004, 2008 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.ltk.core.refactoring;
/**
* Comparator class to compare two refactoring status entries. The general
* contract of this class is equivalent to the one of class
* {@link java.util.Comparator}from the Java Collection Framework.
* <p>
* This interface is intended to be implemented by clients.
* </p>
*
* @since 3.1
*/
public interface IRefactoringStatusEntryComparator {
/**
* Compares two refactoring status entries for order. Returns a negative
* integer, zero, or a positive integer as the first status entry is less
* than, equal to, or greater than the second.
* <p>
* The implementor must ensure that <tt>sgn(compare(x, y)) ==
* -sgn(compare(y, x))</tt>
* for all <tt>x</tt> and <tt>y</tt>.
* </p>
* <p>
* The implementor must ensure that the relation is transitive:
* <tt>((compare(x, y)>0) && (compare(y, z)>0))</tt> implies
* <tt>compare(x, z)>0</tt>.
* </p>
* <p>
* Furthermore, the implementer must ensure that <tt>compare(x, y)==0</tt>
* implies that <tt>sgn(compare(x, z))==sgn(compare(y, z))</tt> for all
* <tt>z</tt>.
* </p>
*
* @param entry1 the first refactoring status entry to be compared.
* @param entry2 the second refactoring status entry to be compared.
* @return a negative integer, zero, or a positive integer as the first
* status entry is less than, equal to, or greater than the second.
*/
public int compare(RefactoringStatusEntry entry1, RefactoringStatusEntry entry2);
}