| /******************************************************************************* |
| * Copyright (c) 2000, 2013 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; |
| |
| import java.util.Enumeration; |
| |
| /** |
| * The <code>LRUCacheEnumerator</code> returns its elements in |
| * the order they are found in the <code>LRUCache</code>, with the |
| * most recent elements first. |
| * |
| * Once the enumerator is created, elements which are later added |
| * to the cache are not returned by the enumerator. However, |
| * elements returned from the enumerator could have been closed |
| * by the cache. |
| */ |
| @SuppressWarnings("rawtypes") |
| public class LRUCacheEnumerator implements Enumeration { |
| /** |
| * Current element; |
| */ |
| protected LRUEnumeratorElement elementQueue; |
| |
| public static class LRUEnumeratorElement { |
| /** |
| * Value returned by <code>nextElement()</code>; |
| */ |
| public Object value; |
| |
| /** |
| * Next element |
| */ |
| public LRUEnumeratorElement next; |
| |
| /** |
| * Constructor |
| */ |
| public LRUEnumeratorElement(Object value) { |
| this.value = value; |
| } |
| } |
| /** |
| * Creates a CacheEnumerator on the list of <code>LRUEnumeratorElements</code>. |
| */ |
| public LRUCacheEnumerator(LRUEnumeratorElement firstElement) { |
| this.elementQueue = firstElement; |
| } |
| /** |
| * Returns true if more elements exist. |
| */ |
| public boolean hasMoreElements() { |
| return this.elementQueue != null; |
| } |
| /** |
| * Returns the next element. |
| */ |
| public Object nextElement() { |
| Object temp = this.elementQueue.value; |
| this.elementQueue = this.elementQueue.next; |
| return temp; |
| } |
| } |