Java tutorial
/* * 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.cocoon.el.impl.objectmodel; import java.util.Collection; import java.util.Map; import java.util.Set; import org.apache.commons.collections.IterableMap; import org.apache.commons.collections.MapIterator; import org.apache.commons.collections.MultiMap; import org.apache.commons.collections.Unmodifiable; import org.apache.commons.collections.collection.UnmodifiableCollection; import org.apache.commons.collections.iterators.EntrySetMapIterator; import org.apache.commons.collections.iterators.UnmodifiableMapIterator; import org.apache.commons.collections.map.AbstractMapDecorator; import org.apache.commons.collections.map.UnmodifiableEntrySet; import org.apache.commons.collections.map.UnmodifiableMap; import org.apache.commons.collections.set.UnmodifiableSet; /** * <p>This class brings equally the same functionality as {@link UnmodifiableMap} but also implements {@link MultiMap} interface.</p> * * <p>Use this class to wrap {@link MultiMap MultiMaps} only.</p> */ public class UnmodifiableMultiMap extends AbstractMapDecorator implements MultiMap, IterableMap, Unmodifiable { public static MultiMap decorate(MultiMap map) { if (map instanceof UnmodifiableMultiMap) return map; return new UnmodifiableMultiMap(map); } private UnmodifiableMultiMap(MultiMap map) { super(map); } /* (non-Javadoc) * @see org.apache.commons.collections.MultiMap#values() */ public Collection values() { Collection coll = super.values(); return UnmodifiableCollection.decorate(coll); } /* (non-Javadoc) * @see java.util.Map#entrySet() */ public Set entrySet() { Set set = super.entrySet(); return UnmodifiableEntrySet.decorate(set); } /* (non-Javadoc) * @see java.util.Map#keySet() */ public Set keySet() { Set set = super.keySet(); return UnmodifiableSet.decorate(set); } /* (non-Javadoc) * @see org.apache.commons.collections.IterableMap#mapIterator() */ public MapIterator mapIterator() { if (map instanceof IterableMap) { MapIterator it = ((IterableMap) map).mapIterator(); return UnmodifiableMapIterator.decorate(it); } else { MapIterator it = new EntrySetMapIterator(map); return UnmodifiableMapIterator.decorate(it); } } //----------------------------------------------------------------------- public void clear() { throw new UnsupportedOperationException(); } public Object put(Object key, Object value) { throw new UnsupportedOperationException(); } public void putAll(Map mapToCopy) { throw new UnsupportedOperationException(); } public Object remove(Object key) { throw new UnsupportedOperationException(); } public Object remove(Object key, Object item) { throw new UnsupportedOperationException(); } }