    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 *      https://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.multimap;
    018
    019import java.util.Collection;
    020import java.util.Map;
    021import java.util.Map.Entry;
    022import java.util.Set;
    023
    024import org.apache.commons.collections4.MapIterator;
    025import org.apache.commons.collections4.MultiSet;
    026import org.apache.commons.collections4.MultiValuedMap;
    027import org.apache.commons.collections4.Unmodifiable;
    028import org.apache.commons.collections4.collection.UnmodifiableCollection;
    029import org.apache.commons.collections4.iterators.UnmodifiableMapIterator;
    030import org.apache.commons.collections4.map.UnmodifiableMap;
    031import org.apache.commons.collections4.multiset.UnmodifiableMultiSet;
    032import org.apache.commons.collections4.set.UnmodifiableSet;
    033
    034/**
    035 * Decorates another {@link MultiValuedMap} to ensure it can't be altered.
    036 * <p>
    037 * Attempts to modify it will result in an UnsupportedOperationException.
    038 * </p>
    039 *
    040 * @param <K> The type of key elements
    041 * @param <V> The type of value elements
    042 * @since 4.1
    043 */
    044public final class UnmodifiableMultiValuedMap<K, V>
    045        extends AbstractMultiValuedMapDecorator<K, V> implements Unmodifiable {
    046
    047    /** Serialization version */
    048    private static final long serialVersionUID = 20150612L;
    049
    050    /**
    051     * Factory method to create an unmodifiable MultiValuedMap.
    052     * <p>
    053     * If the map passed in is already unmodifiable, it is returned.
    054     * </p>
    055     *
    056     * @param <K> The type of key elements
    057     * @param <V> The type of value elements
    058     * @param map  The map to decorate, may not be null
    059     * @return An unmodifiable MultiValuedMap
    060     * @throws NullPointerException if map is null
    061     */
    062    @SuppressWarnings("unchecked")
    063    public static <K, V> UnmodifiableMultiValuedMap<K, V> unmodifiableMultiValuedMap(
    064            final MultiValuedMap<? extends K, ? extends V> map) {
    065        if (map instanceof Unmodifiable) {
    066            return (UnmodifiableMultiValuedMap<K, V>) map;
    067        }
    068        return new UnmodifiableMultiValuedMap<>(map);
    069    }
    070
    071    /**
    072     * Constructor that wraps (not copies).
    073     *
    074     * @param map  The MultiValuedMap to decorate, may not be null
    075     * @throws NullPointerException if the map is null
    076     */
    077    @SuppressWarnings("unchecked")
    078    private UnmodifiableMultiValuedMap(final MultiValuedMap<? extends K, ? extends V> map) {
    079        super((MultiValuedMap<K, V>) map);
    080    }
    081
    082    @Override
    083    public Map<K, Collection<V>> asMap() {
    084        return UnmodifiableMap.unmodifiableMap(decorated().asMap());
    085    }
    086
    087    /**
    088     * Always throws {@link UnsupportedOperationException}.
    089     *
    090     * @throws UnsupportedOperationException Always thrown.
    091     */
    092    @Override
    093    public void clear() {
    094        throw new UnsupportedOperationException();
    095    }
    096
    097    @Override
    098    public Collection<Entry<K, V>> entries() {
    099        return UnmodifiableCollection.unmodifiableCollection(decorated().entries());
    100    }
    101
    102    @Override
    103    public Collection<V> get(final K key) {
    104        return UnmodifiableCollection.unmodifiableCollection(decorated().get(key));
    105    }
    106
    107    @Override
    108    public MultiSet<K> keys() {
    109        return UnmodifiableMultiSet.unmodifiableMultiSet(decorated().keys());
    110    }
    111
    112    @Override
    113    public Set<K> keySet() {
    114        return UnmodifiableSet.unmodifiableSet(decorated().keySet());
    115    }
    116
    117    /**
    118     * {@inheritDoc}
    119     * <p>
    120     * The returned map iterator's {@link MapIterator#setValue(Object)} method is not supported
    121     * and will throw an {@link UnsupportedOperationException}.
    122     * </p>
    123     */
    124    @Override
    125    public MapIterator<K, V> mapIterator() {
    126        return UnmodifiableMapIterator.unmodifiableMapIterator(decorated().mapIterator());
    127    }
    128
    129    /**
    130     * Always throws {@link UnsupportedOperationException}.
    131     *
    132     * @param key Ignored.
    133     * @throws UnsupportedOperationException Always thrown.
    134     */
    135    @Override
    136    public boolean put(final K key, final V value) {
    137        throw new UnsupportedOperationException();
    138    }
    139
    140    /**
    141     * Always throws {@link UnsupportedOperationException}.
    142     *
    143     * @param key Ignored.
    144     * @param values Ignored.
    145     * @throws UnsupportedOperationException Always thrown.
    146     */
    147    @Override
    148    public boolean putAll(final K key, final Iterable<? extends V> values) {
    149        throw new UnsupportedOperationException();
    150    }
    151
    152    /**
    153     * Always throws {@link UnsupportedOperationException}.
    154     *
    155     * @param map Ignored.
    156     * @throws UnsupportedOperationException Always thrown.
    157     */
    158    @Override
    159    public boolean putAll(final Map<? extends K, ? extends V> map) {
    160        throw new UnsupportedOperationException();
    161    }
    162
    163    /**
    164     * Always throws {@link UnsupportedOperationException}.
    165     *
    166     * @param map Ignored.
    167     * @throws UnsupportedOperationException Always thrown.
    168     */
    169    @Override
    170    public boolean putAll(final MultiValuedMap<? extends K, ? extends V> map) {
    171        throw new UnsupportedOperationException();
    172    }
    173
    174    /**
    175     * Always throws {@link UnsupportedOperationException}.
    176     *
    177     * @param key Ignored.
    178     * @throws UnsupportedOperationException Always thrown.
    179     */
    180    @Override
    181    public Collection<V> remove(final Object key) {
    182        throw new UnsupportedOperationException();
    183    }
    184
    185    /**
    186     * Always throws {@link UnsupportedOperationException}.
    187     *
    188     * @param key Ignored.
    189     * @param item Ignored.
    190     * @throws UnsupportedOperationException Always thrown.
    191     */
    192    @Override
    193    public boolean removeMapping(final Object key, final Object item) {
    194        throw new UnsupportedOperationException();
    195    }
    196
    197    @Override
    198    public Collection<V> values() {
    199        return UnmodifiableCollection.unmodifiableCollection(decorated().values());
    200    }
    201
    202}