/*
* 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.catalina.util;
import java.util.LinkedHashMap;
import java.util.Map;
import org.apache.tomcat.util.res.StringManager;
/**
* Extended implementation of <strong>HashMap</strong> that includes a
* <code>locked</code> property. This class can be used to safely expose
* Catalina internal parameter map objects to user classes without having
* to clone them in order to avoid modifications. When first created, a
* <code>ParmaeterMap</code> instance is not locked.
*
* @author Craig R. McClanahan
*/
public final class ParameterMap<K,V> extends LinkedHashMap<K,V> {
private static final long serialVersionUID = 1L;
// ----------------------------------------------------------- Constructors
/**
* Construct a new, empty map with the default initial capacity and
* load factor.
*/
public ParameterMap() {
super();
}
/**
* Construct a new, empty map with the specified initial capacity and
* default load factor.
*
* @param initialCapacity The initial capacity of this map
*/
public ParameterMap(int initialCapacity) {
super(initialCapacity);
}
/**
* Construct a new, empty map with the specified initial capacity and
* load factor.
*
* @param initialCapacity The initial capacity of this map
* @param loadFactor The load factor of this map
*/
public ParameterMap(int initialCapacity, float loadFactor) {
super(initialCapacity, loadFactor);
}
/**
* Construct a new map with the same mappings as the given map.
*
* @param map Map whose contents are duplicated in the new map
*/
public ParameterMap(Map<K,V> map) {
super(map);
}
// ------------------------------------------------------------- Properties
/**
* The current lock state of this parameter map.
*/
private boolean locked = false;
/**
* Return the locked state of this parameter map.
*/
public boolean isLocked() {
return (this.locked);
}
/**
* Set the locked state of this parameter map.
*
* @param locked The new locked state
*/
public void setLocked(boolean locked) {
this.locked = locked;
}
/**
* The string manager for this package.
*/
private static final StringManager sm =
StringManager.getManager("org.apache.catalina.util");
// --------------------------------------------------------- Public Methods
/**
* Remove all mappings from this map.
*
* @exception IllegalStateException if this map is currently locked
*/
@Override
public void clear() {
if (locked)
throw new IllegalStateException
(sm.getString("parameterMap.locked"));
super.clear();
}
/**
* Associate the specified value with the specified key in this map. If
* the map previously contained a mapping for this key, the old value is
* replaced.
*
* @param key Key with which the specified value is to be associated
* @param value Value to be associated with the specified key
*
* @return The previous value associated with the specified key, or
* <code>null</code> if there was no mapping for key
*
* @exception IllegalStateException if this map is currently locked
*/
@Override
public V put(K key, V value) {
if (locked)
throw new IllegalStateException
(sm.getString("parameterMap.locked"));
return (super.put(key, value));
}
/**
* Copy all of the mappings from the specified map to this one. These
* mappings replace any mappings that this map had for any of the keys
* currently in the specified Map.
*
* @param map Mappings to be stored into this map
*
* @exception IllegalStateException if this map is currently locked
*/
@Override
public void putAll(Map<? extends K,? extends V> map) {
if (locked)
throw new IllegalStateException
(sm.getString("parameterMap.locked"));
super.putAll(map);
}
/**
* Remove the mapping for this key from the map if present.
*
* @param key Key whose mapping is to be removed from the map
*
* @return The previous value associated with the specified key, or
* <code>null</code> if there was no mapping for that key
*
* @exception IllegalStateException if this map is currently locked
*/
@Override
public V remove(Object key) {
if (locked)
throw new IllegalStateException
(sm.getString("parameterMap.locked"));
return (super.remove(key));
}
}