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 */
017package org.apache.commons.collections4.set;
018
019import java.util.Comparator;
020import java.util.Set;
021import 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 * @param <E> the type of the elements in the sorted set
029 * @since 3.0
030 * @version $Id: AbstractSortedSetDecorator.html 972421 2015-11-14 20:00:04Z tn $
031 */
032public abstract class AbstractSortedSetDecorator<E>
033        extends AbstractSetDecorator<E>
034        implements SortedSet<E> {
035
036    /** Serialization version */
037    private static final long serialVersionUID = -3462240946294214398L;
038
039    /**
040     * Constructor only used in deserialization, do not use otherwise.
041     * @since 3.1
042     */
043    protected AbstractSortedSetDecorator() {
044        super();
045    }
046
047    /**
048     * Constructor that wraps (not copies).
049     *
050     * @param set  the set to decorate, must not be null
051     * @throws IllegalArgumentException if set is null
052     */
053    protected AbstractSortedSetDecorator(final Set<E> set) {
054        super(set);
055    }
056
057    /**
058     * Gets the set being decorated.
059     *
060     * @return the decorated set
061     */
062    @Override
063    protected SortedSet<E> decorated() {
064        return (SortedSet<E>) super.decorated();
065    }
066
067    //-----------------------------------------------------------------------
068    public SortedSet<E> subSet(final E fromElement, final E toElement) {
069        return decorated().subSet(fromElement, toElement);
070    }
071
072    public SortedSet<E> headSet(final E toElement) {
073        return decorated().headSet(toElement);
074    }
075
076    public SortedSet<E> tailSet(final E fromElement) {
077        return decorated().tailSet(fromElement);
078    }
079
080    public E first() {
081        return decorated().first();
082    }
083
084    public E last() {
085        return decorated().last();
086    }
087
088    public Comparator<? super E> comparator() {
089        return decorated().comparator();
090    }
091
092}