/*******************************************************************************
* Copyright (c) 2000, 2009 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.jdt.internal.core.util;
import java.util.Enumeration;
/**
* The <code>ICacheEnumeration</code> is used to iterate over both the keys and values in an
* LRUCache. The <code>getValue()</code> method returns the value of the last key to be retrieved
* using <code>nextElement()</code>. The <code>nextElement()</code> method must be called before the
* <code>getValue()</code> method.
*
* <p>
* The iteration can be made efficient by making use of the fact that values in the cache (instances
* of <code>LRUCacheEntry</code>), know their key. For this reason, Hashtable lookups don't have to
* be made at each step of the iteration.
*
* <p>
* Modifications to the cache must not be performed while using the enumeration. Doing so will lead
* to an illegal state.
*
* @see LRUCache
*/
public interface ICacheEnumeration extends Enumeration {
/**
* Returns the value of the previously accessed key in the enumeration. Must be called after a
* call to nextElement().
*
* @return Value of current cache entry
*/
public Object getValue();
}