/*
* $Id: RequestMap.java 911398 2010-02-18 13:45:08Z lukaszlenart $
*
* 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.dispatcher;
import javax.servlet.http.HttpServletRequest;
import java.io.Serializable;
import java.util.AbstractMap;
import java.util.Enumeration;
import java.util.HashSet;
import java.util.Set;
/**
* A simple implementation of the {@link java.util.Map} interface to handle a collection of request attributes.
*/
public class RequestMap extends AbstractMap implements Serializable {
private static final long serialVersionUID = -7675640869293787926L;
private Set<Object> entries;
private HttpServletRequest request;
/**
* Saves the request to use as the backing for getting and setting values
*
* @param request the http servlet request.
*/
public RequestMap(final HttpServletRequest request) {
this.request = request;
}
/**
* 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 http request.
*
* @return a Set of attributes from the http 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) {
if (!(obj instanceof Entry)) {
return false;
}
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) {
Object oldValue = get(key);
entries = null;
request.setAttribute(key.toString(), value);
return oldValue;
}
/**
* 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;
}
}
|