001 /*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017 package org.apache.commons.collections.set;
018
019 import java.util.Comparator;
020 import java.util.Set;
021 import java.util.SortedSet;
022
023 /**
024 * Decorates another <code>SortedSet</code> to provide additional behaviour.
025 * <p>
026 * Methods are forwarded directly to the decorated set.
027 *
028 * @since Commons Collections 3.0
029 * @version $Revision: 646777 $ $Date: 2008-04-10 13:33:15 +0100 (Thu, 10 Apr 2008) $
030 *
031 * @author Stephen Colebourne
032 */
033 public abstract class AbstractSortedSetDecorator extends AbstractSetDecorator implements SortedSet {
034
035 /**
036 * Constructor only used in deserialization, do not use otherwise.
037 * @since Commons Collections 3.1
038 */
039 protected AbstractSortedSetDecorator() {
040 super();
041 }
042
043 /**
044 * Constructor that wraps (not copies).
045 *
046 * @param set the set to decorate, must not be null
047 * @throws IllegalArgumentException if set is null
048 */
049 protected AbstractSortedSetDecorator(Set set) {
050 super(set);
051 }
052
053 /**
054 * Gets the sorted set being decorated.
055 *
056 * @return the decorated set
057 */
058 protected SortedSet getSortedSet() {
059 return (SortedSet) getCollection();
060 }
061
062 //-----------------------------------------------------------------------
063 public SortedSet subSet(Object fromElement, Object toElement) {
064 return getSortedSet().subSet(fromElement, toElement);
065 }
066
067 public SortedSet headSet(Object toElement) {
068 return getSortedSet().headSet(toElement);
069 }
070
071 public SortedSet tailSet(Object fromElement) {
072 return getSortedSet().tailSet(fromElement);
073 }
074
075 public Object first() {
076 return getSortedSet().first();
077 }
078
079 public Object last() {
080 return getSortedSet().last();
081 }
082
083 public Comparator comparator() {
084 return getSortedSet().comparator();
085 }
086
087 }