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} to provide additional behavior.
025 * <p>
026 * Methods are forwarded directly to the decorated set.
027 * </p>
028 *
029 * @param <E> the type of the elements in the sorted set
030 * @since 3.0
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    }
045
046    /**
047     * Constructor that wraps (not copies).
048     *
049     * @param set  the set to decorate, must not be null
050     * @throws NullPointerException if set is null
051     */
052    protected AbstractSortedSetDecorator(final Set<E> set) {
053        super(set);
054    }
055
056    @Override
057    public Comparator<? super E> comparator() {
058        return decorated().comparator();
059    }
060
061    /**
062     * Gets the set being decorated.
063     *
064     * @return the decorated set
065     */
066    @Override
067    protected SortedSet<E> decorated() {
068        return (SortedSet<E>) super.decorated();
069    }
070
071    @Override
072    public E first() {
073        return decorated().first();
074    }
075
076    @Override
077    public SortedSet<E> headSet(final E toElement) {
078        return decorated().headSet(toElement);
079    }
080
081    @Override
082    public E last() {
083        return decorated().last();
084    }
085
086    @Override
087    public SortedSet<E> subSet(final E fromElement, final E toElement) {
088        return decorated().subSet(fromElement, toElement);
089    }
090
091    @Override
092    public SortedSet<E> tailSet(final E fromElement) {
093        return decorated().tailSet(fromElement);
094    }
095
096}