    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     * Constructor that wraps (not copies).
    052     *
    053     * @param bag  the sorted bag to decorate, must not be null
    054     * @throws NullPointerException if bag is null
    055     */
    056    public CollectionSortedBag(final SortedBag<E> bag) {
    057        super(bag);
    058    }
    059
    060    @Override
    061    public boolean add(final E object) {
    062        return add(object, 1);
    063    }
    064
    065    @Override
    066    public boolean add(final E object, final int count) {
    067        decorated().add(object, count);
    068        return true;
    069    }
    070
    071    // Collection interface
    072
    073    @Override
    074    public boolean addAll(final Collection<? extends E> coll) {
    075        boolean changed = false;
    076        for (final E current : coll) {
    077            final boolean added = add(current, 1);
    078            changed = changed || added;
    079        }
    080        return changed;
    081    }
    082
    083    @Override
    084    public boolean containsAll(final Collection<?> coll) {
    085        return coll.stream().allMatch(this::contains);
    086    }
    087
    088    /**
    089     * Read the collection in using a custom routine.
    090     *
    091     * @param in  the input stream
    092     * @throws IOException if an error occurs while reading from the stream
    093     * @throws ClassNotFoundException if an object read from the stream can not be loaded
    094     * @throws ClassCastException if deserialized object has wrong type
    095     */
    096    @SuppressWarnings("unchecked") // will throw CCE, see Javadoc
    097    private void readObject(final ObjectInputStream in) throws IOException, ClassNotFoundException {
    098        in.defaultReadObject();
    099        setCollection((Collection<E>) in.readObject());
    100    }
    101
    102    @Override
    103    public boolean remove(final Object object) {
    104        return remove(object, 1);
    105    }
    106
    107    @Override
    108    public boolean removeAll(final Collection<?> coll) {
    109        if (coll != null) {
    110            boolean result = false;
    111            for (final Object obj : coll) {
    112                final boolean changed = remove(obj, getCount(obj));
    113                result = result || changed;
    114            }
    115            return result;
    116        }
    117        // let the decorated bag handle the case of null argument
    118        return decorated().removeAll(null);
    119    }
    120
    121    @Override
    122    public boolean retainAll(final Collection<?> coll) {
    123        if (coll != null) {
    124            boolean modified = false;
    125            final Iterator<E> e = iterator();
    126            while (e.hasNext()) {
    127                if (!coll.contains(e.next())) {
    128                    e.remove();
    129                    modified = true;
    130                }
    131            }
    132            return modified;
    133        }
    134        // let the decorated bag handle the case of null argument
    135        return decorated().retainAll(null);
    136    }
    137
    138    // Bag interface
    139
    140    /**
    141     * Write the collection out using a custom routine.
    142     *
    143     * @param out  the output stream
    144     * @throws IOException if an error occurs while writing to the stream
    145     */
    146    private void writeObject(final ObjectOutputStream out) throws IOException {
    147        out.defaultWriteObject();
    148        out.writeObject(decorated());
    149    }
    150
    151}