    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.bag;
    018
    019import java.io.IOException;
    020import java.io.ObjectInputStream;
    021import java.io.ObjectOutputStream;
    022import java.util.Collection;
    023import java.util.Iterator;
    024
    025import org.apache.commons.collections4.SortedBag;
    026
    027/**
    028 * Decorates another {@link SortedBag} to comply with the Collection contract.
    029 *
    030 * @param <E> the type of elements in this bag
    031 * @since 4.0
    032 */
    033public final class CollectionSortedBag<E> extends AbstractSortedBagDecorator<E> {
    034
    035    /** Serialization version */
    036    private static final long serialVersionUID = -2560033712679053143L;
    037
    038    /**
    039     * Factory method to create a sorted bag that complies to the Collection contract.
    040     *
    041     * @param <E> the type of the elements in the bag
    042     * @param bag  the sorted bag to decorate, must not be null
    043     * @return a SortedBag that complies to the Collection contract
    044     * @throws NullPointerException if bag is null
    045     */
    046    public static <E> SortedBag<E> collectionSortedBag(final SortedBag<E> bag) {
    047        return new CollectionSortedBag<>(bag);
    048    }
    049
    050    //-----------------------------------------------------------------------
    051    /**
    052     * Constructor that wraps (not copies).
    053     *
    054     * @param bag  the sorted bag to decorate, must not be null
    055     * @throws NullPointerException if bag is null
    056     */
    057    public CollectionSortedBag(final SortedBag<E> bag) {
    058        super(bag);
    059    }
    060
    061    //-----------------------------------------------------------------------
    062    /**
    063     * Write the collection out using a custom routine.
    064     *
    065     * @param out  the output stream
    066     * @throws IOException if an error occurs while writing to the stream
    067     */
    068    private void writeObject(final ObjectOutputStream out) throws IOException {
    069        out.defaultWriteObject();
    070        out.writeObject(decorated());
    071    }
    072
    073    /**
    074     * Read the collection in using a custom routine.
    075     *
    076     * @param in  the input stream
    077     * @throws IOException if an error occurs while reading from the stream
    078     * @throws ClassNotFoundException if an object read from the stream can not be loaded
    079     * @throws ClassCastException if deserialised object has wrong type
    080     */
    081    @SuppressWarnings("unchecked") // will throw CCE, see Javadoc
    082    private void readObject(final ObjectInputStream in) throws IOException, ClassNotFoundException {
    083        in.defaultReadObject();
    084        setCollection((Collection<E>) in.readObject());
    085    }
    086
    087    //-----------------------------------------------------------------------
    088    // Collection interface
    089    //-----------------------------------------------------------------------
    090
    091    @Override
    092    public boolean containsAll(final Collection<?> coll) {
    093        final Iterator<?> e = coll.iterator();
    094        while (e.hasNext()) {
    095            if(!contains(e.next())) {
    096                return false;
    097            }
    098        }
    099        return true;
    100    }
    101
    102    @Override
    103    public boolean add(final E object) {
    104        return add(object, 1);
    105    }
    106
    107    @Override
    108    public boolean addAll(final Collection<? extends E> coll) {
    109        boolean changed = false;
    110        final Iterator<? extends E> i = coll.iterator();
    111        while (i.hasNext()) {
    112            final boolean added = add(i.next(), 1);
    113            changed = changed || added;
    114        }
    115        return changed;
    116    }
    117
    118    @Override
    119    public boolean remove(final Object object) {
    120        return remove(object, 1);
    121    }
    122
    123    @Override
    124    public boolean removeAll(final Collection<?> coll) {
    125        if (coll != null) {
    126            boolean result = false;
    127            final Iterator<?> i = coll.iterator();
    128            while (i.hasNext()) {
    129                final Object obj = i.next();
    130                final boolean changed = remove(obj, getCount(obj));
    131                result = result || changed;
    132            }
    133            return result;
    134        }
    135        // let the decorated bag handle the case of null argument
    136        return decorated().removeAll(null);
    137    }
    138
    139    @Override
    140    public boolean retainAll(final Collection<?> coll) {
    141        if (coll != null) {
    142            boolean modified = false;
    143            final Iterator<E> e = iterator();
    144            while (e.hasNext()) {
    145                if (!coll.contains(e.next())) {
    146                    e.remove();
    147                    modified = true;
    148                }
    149            }
    150            return modified;
    151        }
    152        // let the decorated bag handle the case of null argument
    153        return decorated().retainAll(null);
    154    }
    155
    156    //-----------------------------------------------------------------------
    157    // Bag interface
    158    //-----------------------------------------------------------------------
    159
    160    @Override
    161    public boolean add(final E object, final int count) {
    162        decorated().add(object, count);
    163        return true;
    164    }
    165
    166}