j2ee项目使用filter和memcached实现session服务器

package com.laoer.session; import java.util.Collection; import java.util.Enumeration; import java.util.Iterator; import java.util.List; import java.util.ArrayList; import java.util.Map; import java.util.NoSuchElementException; public class Enumerator implements Enumeration { // ----------------------------------------------------------- Constructors /** * Return an Enumeration over the values of the specified Collection. * * @param collection * Collection whose values should be enumerated */ public Enumerator(Collection collection) { this(collection.iterator()); } /** * Return an Enumeration over the values of the specified Collection. * * @param collection * Collection whose values should be enumerated * @param clone * true to clone iterator */ public Enumerator(Collection collection, boolean clone) { this(collection.iterator(), clone); } /** * Return an Enumeration over the values returned by the specified Iterator. * * @param iterator * Iterator to be wrapped */ public Enumerator(Iterator iterator) { super(); this.iterator = iterator; } /** * Return an Enumeration over the values returned by the specified Iterator. * * @param iterator * Iterator to be wrapped * @param clone * true to clone iterator */ @SuppressWarnings("unchecked") public Enumerator(Iterator iterator, boolean clone) { super(); if (!clone) { this.iterator = iterator; } else { List list = new ArrayList(); while (iterator.hasNext()) { list.add(iterator.next()); } this.iterator = list.iterator(); } } /** * Return an Enumeration over the values of the specified Map. * * @param map * Map whose values should be enumerated */ public Enumerator(Map map) { this(map.values().iterator()); } /** * Return an Enumeration over the values of the specified Map. * * @param map * Map whose values should be enumerated * @param clone * true to clone iterator */ public Enumerator(Map map, boolean clone) { this(map.values().iterator(), clone); } // ----------------------------------------------------- Instance Variables /** * The <code>Iterator</code> over which the <code>Enumeration</code> * represented by this class actually operates. */ private Iterator iterator = null; // --------------------------------------------------------- Public Methods /** * Tests if this enumeration contains more elements. * * @return <code>true</code> if and only if this enumeration object * contains at least one more element to provide, <code>false</code> * otherwise */ public boolean hasMoreElements() { return (iterator.hasNext()); } /** * Returns the next element of this enumeration if this enumeration has at * least one more element to provide. * * @return the next element of this enumeration * * @exception NoSuchElementException * if no more elements exist */ public Object nextElement() throws NoSuchElementException { return (iterator.next()); } }