Java tutorial
/* * $Id: PortletRequestMap.java 471756 2006-11-06 15:01:43Z husted $ * * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, * software distributed under the License is distributed on an * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY * KIND, either express or implied. See the License for the * specific language governing permissions and limitations * under the License. */ package org.apache.struts2.portlet; import java.util.AbstractMap; import java.util.Enumeration; import java.util.HashSet; import java.util.Iterator; import java.util.Set; import javax.portlet.PortletRequest; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; /** * A simple implementation of the {@link java.util.Map} interface to handle a collection of request attributes. * */ public class PortletRequestMap extends AbstractMap { private static final Log LOG = LogFactory.getLog(PortletRequestMap.class); private Set<Object> entries = null; private PortletRequest request = null; /** * Saves the request to use as the backing for getting and setting values * * @param request the portlet request. */ public PortletRequestMap(PortletRequest request) { this.request = request; if (LOG.isDebugEnabled()) { LOG.debug("Dumping request parameters: "); Iterator params = request.getParameterMap().keySet().iterator(); while (params.hasNext()) { String key = (String) params.next(); String val = request.getParameter(key); LOG.debug(key + " = " + val); } } } /** * Removes all attributes from the request as well as clears entries in this * map. */ public void clear() { entries = null; Enumeration keys = request.getAttributeNames(); while (keys.hasMoreElements()) { String key = (String) keys.nextElement(); request.removeAttribute(key); } } /** * Returns a Set of attributes from the portlet request. * * @return a Set of attributes from the portlet request. */ public Set entrySet() { if (entries == null) { entries = new HashSet<Object>(); Enumeration enumeration = request.getAttributeNames(); while (enumeration.hasMoreElements()) { final String key = enumeration.nextElement().toString(); final Object value = request.getAttribute(key); entries.add(new Entry() { public boolean equals(Object obj) { Entry entry = (Entry) obj; return ((key == null) ? (entry.getKey() == null) : key.equals(entry.getKey())) && ((value == null) ? (entry.getValue() == null) : value.equals(entry.getValue())); } public int hashCode() { return ((key == null) ? 0 : key.hashCode()) ^ ((value == null) ? 0 : value.hashCode()); } public Object getKey() { return key; } public Object getValue() { return value; } public Object setValue(Object obj) { request.setAttribute(key, obj); return value; } }); } } return entries; } /** * Returns the request attribute associated with the given key or * <tt>null</tt> if it doesn't exist. * * @param key the name of the request attribute. * @return the request attribute or <tt>null</tt> if it doesn't exist. */ public Object get(Object key) { return request.getAttribute(key.toString()); } /** * Saves an attribute in the request. * * @param key the name of the request attribute. * @param value the value to set. * @return the object that was just set. */ public Object put(Object key, Object value) { entries = null; request.setAttribute(key.toString(), value); return get(key); } /** * Removes the specified request attribute. * * @param key the name of the attribute to remove. * @return the value that was removed or <tt>null</tt> if the value was * not found (and hence, not removed). */ public Object remove(Object key) { entries = null; Object value = get(key); request.removeAttribute(key.toString()); return value; } }