MultiKeyMap.java
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.commons.collections4.map;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.util.Map;
import java.util.Objects;
import org.apache.commons.collections4.MapIterator;
import org.apache.commons.collections4.keyvalue.MultiKey;
import org.apache.commons.collections4.map.AbstractHashedMap.HashEntry;
/**
* A {@code Map} implementation that uses multiple keys to map the value.
* <p>
* This class is the most efficient way to uses multiple keys to map to a value.
* The best way to use this class is via the additional map-style methods.
* These provide {@code get}, {@code containsKey}, {@code put} and
* {@code remove} for individual keys which operate without extra object creation.
* </p>
* <p>
* The additional methods are the main interface of this map.
* As such, you will not normally hold this map in a variable of type {@code Map}.
* </p>
* <p>
* The normal map methods take in and return a {@link MultiKey}.
* If you try to use {@code put()} with any other object type a
* {@code ClassCastException} is thrown. If you try to use {@code null} as
* the key in {@code put()} a {@code NullPointerException} is thrown.
* </p>
* <p>
* This map is implemented as a decorator of a {@code AbstractHashedMap} which
* enables extra behavior to be added easily.
* </p>
* <ul>
* <li>{@code MultiKeyMap.decorate(new LinkedMap())} creates an ordered map.
* <li>{@code MultiKeyMap.decorate(new LRUMap())} creates an least recently used map.
* <li>{@code MultiKeyMap.decorate(new ReferenceMap())} creates a garbage collector sensitive map.
* </ul>
* <p>
* Note that {@code IdentityMap} and {@code ReferenceIdentityMap} are unsuitable
* for use as the key comparison would work on the whole MultiKey, not the elements within.
* </p>
* <p>
* As an example, consider a least recently used cache that uses a String airline code
* and a Locale to lookup the airline's name:
* </p>
* <pre>
* private MultiKeyMap cache = MultiKeyMap.multiKeyMap(new LRUMap(50));
*
* public String getAirlineName(String code, String locale) {
* String name = (String) cache.get(code, locale);
* if (name == null) {
* name = getAirlineNameFromDB(code, locale);
* cache.put(code, locale, name);
* }
* return name;
* }
* </pre>
* <p>
* <strong>Note that MultiKeyMap is not synchronized and is not thread-safe.</strong>
* If you wish to use this map from multiple threads concurrently, you must use
* appropriate synchronization. This class may throw exceptions when accessed
* by concurrent threads without synchronization.
* </p>
*
* @param <K> the type of the keys in this map
* @param <V> the type of the values in this map
* @since 3.1
*/
public class MultiKeyMap<K, V> extends AbstractMapDecorator<MultiKey<? extends K>, V>
implements Serializable, Cloneable {
/** Serialisation version */
private static final long serialVersionUID = -1788199231038721040L;
/**
* Decorates the specified map to add the MultiKeyMap API and fast query.
* The map must not be null and must be empty.
*
* @param <K> the key type
* @param <V> the value type
* @param map the map to decorate, not null
* @return a new multi key map
* @throws NullPointerException if map is null
* @throws IllegalArgumentException if the map is not empty
* @since 4.0
*/
public static <K, V> MultiKeyMap<K, V> multiKeyMap(final AbstractHashedMap<MultiKey<? extends K>, V> map) {
Objects.requireNonNull(map, "map");
if (map.isEmpty()) {
return new MultiKeyMap<>(map);
}
throw new IllegalArgumentException("Map must be empty");
}
/**
* Constructs a new MultiKeyMap that decorates a {@code HashedMap}.
*/
public MultiKeyMap() {
this(new HashedMap<>());
}
/**
* Constructor that decorates the specified map and is called from
* {@link #multiKeyMap(AbstractHashedMap)}.
* The map must not be null and should be empty or only contain valid keys.
* This constructor performs no validation.
*
* @param map the map to decorate
*/
protected MultiKeyMap(final AbstractHashedMap<MultiKey<? extends K>, V> map) {
super(map);
this.map = map;
}
/**
* Check to ensure that input keys are valid MultiKey objects.
*
* @param key the key to check
*/
protected void checkKey(final MultiKey<?> key) {
Objects.requireNonNull(key, "key");
}
/**
* Clones the map without cloning the keys or values.
*
* @return a shallow clone
*/
@SuppressWarnings("unchecked")
@Override
public MultiKeyMap<K, V> clone() {
try {
return (MultiKeyMap<K, V>) super.clone();
} catch (final CloneNotSupportedException e) {
throw new UnsupportedOperationException(e);
}
}
/**
* Checks whether the map contains the specified multi-key.
*
* @param key1 the first key
* @param key2 the second key
* @return true if the map contains the key
*/
public boolean containsKey(final Object key1, final Object key2) {
final int hashCode = hash(key1, key2);
AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> entry = decoratedHashEntry(hashCode);
while (entry != null) {
if (entry.hashCode == hashCode && isEqualKey(entry, key1, key2)) {
return true;
}
entry = entry.next;
}
return false;
}
/**
* Checks whether the map contains the specified multi-key.
*
* @param key1 the first key
* @param key2 the second key
* @param key3 the third key
* @return true if the map contains the key
*/
public boolean containsKey(final Object key1, final Object key2, final Object key3) {
final int hashCode = hash(key1, key2, key3);
AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> entry = decoratedHashEntry(hashCode);
while (entry != null) {
if (entry.hashCode == hashCode && isEqualKey(entry, key1, key2, key3)) {
return true;
}
entry = entry.next;
}
return false;
}
/**
* Checks whether the map contains the specified multi-key.
*
* @param key1 the first key
* @param key2 the second key
* @param key3 the third key
* @param key4 the fourth key
* @return true if the map contains the key
*/
public boolean containsKey(final Object key1, final Object key2, final Object key3, final Object key4) {
final int hashCode = hash(key1, key2, key3, key4);
AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> entry = decoratedHashEntry(hashCode);
while (entry != null) {
if (entry.hashCode == hashCode && isEqualKey(entry, key1, key2, key3, key4)) {
return true;
}
entry = entry.next;
}
return false;
}
/**
* Checks whether the map contains the specified multi-key.
*
* @param key1 the first key
* @param key2 the second key
* @param key3 the third key
* @param key4 the fourth key
* @param key5 the fifth key
* @return true if the map contains the key
*/
public boolean containsKey(final Object key1, final Object key2, final Object key3, final Object key4, final Object key5) {
final int hashCode = hash(key1, key2, key3, key4, key5);
AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> entry = decoratedHashEntry(hashCode);
while (entry != null) {
if (entry.hashCode == hashCode && isEqualKey(entry, key1, key2, key3, key4, key5)) {
return true;
}
entry = entry.next;
}
return false;
}
/**
* {@inheritDoc}
*/
@Override
protected AbstractHashedMap<MultiKey<? extends K>, V> decorated() {
return (AbstractHashedMap<MultiKey<? extends K>, V>) super.decorated();
}
HashEntry<MultiKey<? extends K>, V> decoratedHashEntry(final int hashCode) {
return decorated().data[decoratedHashIndex(hashCode)];
}
int decoratedHashIndex(final int hashCode) {
return decorated().hashIndex(hashCode, decorated().data.length);
}
/**
* Gets the value mapped to the specified multi-key.
*
* @param key1 the first key
* @param key2 the second key
* @return the mapped value, null if no match
*/
public V get(final Object key1, final Object key2) {
final int hashCode = hash(key1, key2);
AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> entry = decoratedHashEntry(hashCode);
while (entry != null) {
if (entry.hashCode == hashCode && isEqualKey(entry, key1, key2)) {
return entry.getValue();
}
entry = entry.next;
}
return null;
}
/**
* Gets the value mapped to the specified multi-key.
*
* @param key1 the first key
* @param key2 the second key
* @param key3 the third key
* @return the mapped value, null if no match
*/
public V get(final Object key1, final Object key2, final Object key3) {
final int hashCode = hash(key1, key2, key3);
AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> entry = decoratedHashEntry(hashCode);
while (entry != null) {
if (entry.hashCode == hashCode && isEqualKey(entry, key1, key2, key3)) {
return entry.getValue();
}
entry = entry.next;
}
return null;
}
/**
* Gets the value mapped to the specified multi-key.
*
* @param key1 the first key
* @param key2 the second key
* @param key3 the third key
* @param key4 the fourth key
* @return the mapped value, null if no match
*/
public V get(final Object key1, final Object key2, final Object key3, final Object key4) {
final int hashCode = hash(key1, key2, key3, key4);
AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> entry = decoratedHashEntry(hashCode);
while (entry != null) {
if (entry.hashCode == hashCode && isEqualKey(entry, key1, key2, key3, key4)) {
return entry.getValue();
}
entry = entry.next;
}
return null;
}
/**
* Gets the value mapped to the specified multi-key.
*
* @param key1 the first key
* @param key2 the second key
* @param key3 the third key
* @param key4 the fourth key
* @param key5 the fifth key
* @return the mapped value, null if no match
*/
public V get(final Object key1, final Object key2, final Object key3, final Object key4, final Object key5) {
final int hashCode = hash(key1, key2, key3, key4, key5);
AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> entry = decoratedHashEntry(hashCode);
while (entry != null) {
if (entry.hashCode == hashCode && isEqualKey(entry, key1, key2, key3, key4, key5)) {
return entry.getValue();
}
entry = entry.next;
}
return null;
}
/**
* Gets the hash code for the specified multi-key.
*
* @param key1 the first key
* @param key2 the second key
* @return the hash code
*/
protected int hash(final Object key1, final Object key2) {
int h = 0;
if (key1 != null) {
h ^= key1.hashCode();
}
if (key2 != null) {
h ^= key2.hashCode();
}
h += ~(h << 9);
h ^= h >>> 14;
h += h << 4;
h ^= h >>> 10;
return h;
}
/**
* Gets the hash code for the specified multi-key.
*
* @param key1 the first key
* @param key2 the second key
* @param key3 the third key
* @return the hash code
*/
protected int hash(final Object key1, final Object key2, final Object key3) {
int h = 0;
if (key1 != null) {
h ^= key1.hashCode();
}
if (key2 != null) {
h ^= key2.hashCode();
}
if (key3 != null) {
h ^= key3.hashCode();
}
h += ~(h << 9);
h ^= h >>> 14;
h += h << 4;
h ^= h >>> 10;
return h;
}
/**
* Gets the hash code for the specified multi-key.
*
* @param key1 the first key
* @param key2 the second key
* @param key3 the third key
* @param key4 the fourth key
* @return the hash code
*/
protected int hash(final Object key1, final Object key2, final Object key3, final Object key4) {
int h = 0;
if (key1 != null) {
h ^= key1.hashCode();
}
if (key2 != null) {
h ^= key2.hashCode();
}
if (key3 != null) {
h ^= key3.hashCode();
}
if (key4 != null) {
h ^= key4.hashCode();
}
h += ~(h << 9);
h ^= h >>> 14;
h += h << 4;
h ^= h >>> 10;
return h;
}
/**
* Gets the hash code for the specified multi-key.
*
* @param key1 the first key
* @param key2 the second key
* @param key3 the third key
* @param key4 the fourth key
* @param key5 the fifth key
* @return the hash code
*/
protected int hash(final Object key1, final Object key2, final Object key3, final Object key4, final Object key5) {
int h = 0;
if (key1 != null) {
h ^= key1.hashCode();
}
if (key2 != null) {
h ^= key2.hashCode();
}
if (key3 != null) {
h ^= key3.hashCode();
}
if (key4 != null) {
h ^= key4.hashCode();
}
if (key5 != null) {
h ^= key5.hashCode();
}
h += ~(h << 9);
h ^= h >>> 14;
h += h << 4;
h ^= h >>> 10;
return h;
}
/**
* Is the key equal to the combined key.
*
* @param entry the entry to compare to
* @param key1 the first key
* @param key2 the second key
* @return true if the key matches
*/
protected boolean isEqualKey(final AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> entry,
final Object key1, final Object key2) {
final MultiKey<? extends K> multi = entry.getKey();
return
multi.size() == 2 &&
Objects.equals(key1, multi.getKey(0)) &&
Objects.equals(key2, multi.getKey(1));
}
/**
* Is the key equal to the combined key.
*
* @param entry the entry to compare to
* @param key1 the first key
* @param key2 the second key
* @param key3 the third key
* @return true if the key matches
*/
protected boolean isEqualKey(final AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> entry,
final Object key1, final Object key2, final Object key3) {
final MultiKey<? extends K> multi = entry.getKey();
return
multi.size() == 3 &&
Objects.equals(key1, multi.getKey(0)) &&
Objects.equals(key2, multi.getKey(1)) &&
Objects.equals(key3, multi.getKey(2));
}
/**
* Is the key equal to the combined key.
*
* @param entry the entry to compare to
* @param key1 the first key
* @param key2 the second key
* @param key3 the third key
* @param key4 the fourth key
* @return true if the key matches
*/
protected boolean isEqualKey(final AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> entry,
final Object key1, final Object key2, final Object key3, final Object key4) {
final MultiKey<? extends K> multi = entry.getKey();
return
multi.size() == 4 &&
Objects.equals(key1, multi.getKey(0)) &&
Objects.equals(key2, multi.getKey(1)) &&
Objects.equals(key3, multi.getKey(2)) &&
Objects.equals(key4, multi.getKey(3));
}
/**
* Is the key equal to the combined key.
*
* @param entry the entry to compare to
* @param key1 the first key
* @param key2 the second key
* @param key3 the third key
* @param key4 the fourth key
* @param key5 the fifth key
* @return true if the key matches
*/
protected boolean isEqualKey(final AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> entry,
final Object key1, final Object key2, final Object key3, final Object key4, final Object key5) {
final MultiKey<? extends K> multi = entry.getKey();
return
multi.size() == 5 &&
Objects.equals(key1, multi.getKey(0)) &&
Objects.equals(key2, multi.getKey(1)) &&
Objects.equals(key3, multi.getKey(2)) &&
Objects.equals(key4, multi.getKey(3)) &&
Objects.equals(key5, multi.getKey(4));
}
@Override
public MapIterator<MultiKey<? extends K>, V> mapIterator() {
return decorated().mapIterator();
}
/**
* Associates the specified value with the specified keys in this map.
*
* @param key1 the first key
* @param key2 the second key
* @param key3 the third key
* @param key4 the fourth key
* @param key5 the fifth key
* @param value the value to store
* @return the value previously mapped to this combined key, null if none
*/
public V put(final K key1, final K key2, final K key3, final K key4, final K key5, final V value) {
final int hashCode = hash(key1, key2, key3, key4, key5);
final int index = decoratedHashIndex(hashCode);
AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> entry = decorated().data[index];
while (entry != null) {
if (entry.hashCode == hashCode && isEqualKey(entry, key1, key2, key3, key4, key5)) {
final V oldValue = entry.getValue();
decorated().updateEntry(entry, value);
return oldValue;
}
entry = entry.next;
}
decorated().addMapping(index, hashCode, new MultiKey<>(key1, key2, key3, key4, key5), value);
return null;
}
/**
* Associates the specified value with the specified keys in this map.
*
* @param key1 the first key
* @param key2 the second key
* @param key3 the third key
* @param key4 the fourth key
* @param value the value to store
* @return the value previously mapped to this combined key, null if none
*/
public V put(final K key1, final K key2, final K key3, final K key4, final V value) {
final int hashCode = hash(key1, key2, key3, key4);
final int index = decoratedHashIndex(hashCode);
AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> entry = decorated().data[index];
while (entry != null) {
if (entry.hashCode == hashCode && isEqualKey(entry, key1, key2, key3, key4)) {
final V oldValue = entry.getValue();
decorated().updateEntry(entry, value);
return oldValue;
}
entry = entry.next;
}
decorated().addMapping(index, hashCode, new MultiKey<>(key1, key2, key3, key4), value);
return null;
}
/**
* Associates the specified value with the specified keys in this map.
*
* @param key1 the first key
* @param key2 the second key
* @param key3 the third key
* @param value the value to store
* @return the value previously mapped to this combined key, null if none
*/
public V put(final K key1, final K key2, final K key3, final V value) {
final int hashCode = hash(key1, key2, key3);
final int index = decoratedHashIndex(hashCode);
AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> entry = decorated().data[index];
while (entry != null) {
if (entry.hashCode == hashCode && isEqualKey(entry, key1, key2, key3)) {
final V oldValue = entry.getValue();
decorated().updateEntry(entry, value);
return oldValue;
}
entry = entry.next;
}
decorated().addMapping(index, hashCode, new MultiKey<>(key1, key2, key3), value);
return null;
}
/**
* Associates the specified value with the specified keys in this map.
*
* @param key1 the first key
* @param key2 the second key
* @param value the value to store
* @return the value previously mapped to this combined key, null if none
*/
public V put(final K key1, final K key2, final V value) {
final int hashCode = hash(key1, key2);
final int index = decoratedHashIndex(hashCode);
AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> entry = decorated().data[index];
while (entry != null) {
if (entry.hashCode == hashCode && isEqualKey(entry, key1, key2)) {
final V oldValue = entry.getValue();
decorated().updateEntry(entry, value);
return oldValue;
}
entry = entry.next;
}
decorated().addMapping(index, hashCode, new MultiKey<>(key1, key2), value);
return null;
}
/**
* Puts the key and value into the map, where the key must be a non-null
* MultiKey object.
*
* @param key the non-null MultiKey object
* @param value the value to store
* @return the previous value for the key
* @throws NullPointerException if the key is null
* @throws ClassCastException if the key is not a MultiKey
*/
@Override
public V put(final MultiKey<? extends K> key, final V value) {
checkKey(key);
return super.put(key, value);
}
/**
* Copies all of the keys and values from the specified map to this map.
* Each key must be non-null and a MultiKey object.
*
* @param mapToCopy to this map
* @throws NullPointerException if the mapToCopy or any key within is null
* @throws ClassCastException if any key in mapToCopy is not a MultiKey
*/
@Override
public void putAll(final Map<? extends MultiKey<? extends K>, ? extends V> mapToCopy) {
for (final MultiKey<? extends K> key : mapToCopy.keySet()) {
checkKey(key);
}
super.putAll(mapToCopy);
}
/**
* Deserializes the map in using a custom routine.
*
* @param in the input stream
* @throws IOException if an error occurs while reading from the stream
* @throws ClassNotFoundException if an object read from the stream cannot be loaded
*/
@SuppressWarnings("unchecked")
private void readObject(final ObjectInputStream in) throws IOException, ClassNotFoundException {
in.defaultReadObject();
map = (Map<MultiKey<? extends K>, V>) in.readObject();
}
/**
* Removes all mappings where the first key is that specified.
* <p>
* This method removes all the mappings where the {@code MultiKey}
* has one or more keys, and the first matches that specified.
* </p>
*
* @param key1 the first key
* @return true if any elements were removed
*/
public boolean removeAll(final Object key1) {
boolean modified = false;
final MapIterator<MultiKey<? extends K>, V> it = mapIterator();
while (it.hasNext()) {
final MultiKey<? extends K> multi = it.next();
if (multi.size() >= 1 &&
Objects.equals(key1, multi.getKey(0))) {
it.remove();
modified = true;
}
}
return modified;
}
/**
* Removes all mappings where the first two keys are those specified.
* <p>
* This method removes all the mappings where the {@code MultiKey}
* has two or more keys, and the first two match those specified.
* </p>
*
* @param key1 the first key
* @param key2 the second key
* @return true if any elements were removed
*/
public boolean removeAll(final Object key1, final Object key2) {
boolean modified = false;
final MapIterator<MultiKey<? extends K>, V> it = mapIterator();
while (it.hasNext()) {
final MultiKey<? extends K> multi = it.next();
if (multi.size() >= 2 &&
Objects.equals(key1, multi.getKey(0)) &&
Objects.equals(key2, multi.getKey(1))) {
it.remove();
modified = true;
}
}
return modified;
}
/**
* Removes all mappings where the first three keys are those specified.
* <p>
* This method removes all the mappings where the {@code MultiKey}
* has three or more keys, and the first three match those specified.
* </p>
*
* @param key1 the first key
* @param key2 the second key
* @param key3 the third key
* @return true if any elements were removed
*/
public boolean removeAll(final Object key1, final Object key2, final Object key3) {
boolean modified = false;
final MapIterator<MultiKey<? extends K>, V> it = mapIterator();
while (it.hasNext()) {
final MultiKey<? extends K> multi = it.next();
if (multi.size() >= 3 &&
Objects.equals(key1, multi.getKey(0)) &&
Objects.equals(key2, multi.getKey(1)) &&
Objects.equals(key3, multi.getKey(2))) {
it.remove();
modified = true;
}
}
return modified;
}
/**
* Removes all mappings where the first four keys are those specified.
* <p>
* This method removes all the mappings where the {@code MultiKey}
* has four or more keys, and the first four match those specified.
* </p>
*
* @param key1 the first key
* @param key2 the second key
* @param key3 the third key
* @param key4 the fourth key
* @return true if any elements were removed
*/
public boolean removeAll(final Object key1, final Object key2, final Object key3, final Object key4) {
boolean modified = false;
final MapIterator<MultiKey<? extends K>, V> it = mapIterator();
while (it.hasNext()) {
final MultiKey<? extends K> multi = it.next();
if (multi.size() >= 4 &&
Objects.equals(key1, multi.getKey(0)) &&
Objects.equals(key2, multi.getKey(1)) &&
Objects.equals(key3, multi.getKey(2)) &&
Objects.equals(key4, multi.getKey(3))) {
it.remove();
modified = true;
}
}
return modified;
}
/**
* Removes the specified multi-key from this map.
*
* @param key1 the first key
* @param key2 the second key
* @return the value mapped to the removed key, null if key not in map
* @since 4.0 (previous name: remove(Object, Object))
*/
public V removeMultiKey(final Object key1, final Object key2) {
final int hashCode = hash(key1, key2);
final int index = decoratedHashIndex(hashCode);
AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> entry = decorated().data[index];
AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> previous = null;
while (entry != null) {
if (entry.hashCode == hashCode && isEqualKey(entry, key1, key2)) {
final V oldValue = entry.getValue();
decorated().removeMapping(entry, index, previous);
return oldValue;
}
previous = entry;
entry = entry.next;
}
return null;
}
/**
* Removes the specified multi-key from this map.
*
* @param key1 the first key
* @param key2 the second key
* @param key3 the third key
* @return the value mapped to the removed key, null if key not in map
* @since 4.0 (previous name: remove(Object, Object, Object))
*/
public V removeMultiKey(final Object key1, final Object key2, final Object key3) {
final int hashCode = hash(key1, key2, key3);
final int index = decoratedHashIndex(hashCode);
AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> entry = decorated().data[index];
AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> previous = null;
while (entry != null) {
if (entry.hashCode == hashCode && isEqualKey(entry, key1, key2, key3)) {
final V oldValue = entry.getValue();
decorated().removeMapping(entry, index, previous);
return oldValue;
}
previous = entry;
entry = entry.next;
}
return null;
}
/**
* Removes the specified multi-key from this map.
*
* @param key1 the first key
* @param key2 the second key
* @param key3 the third key
* @param key4 the fourth key
* @return the value mapped to the removed key, null if key not in map
* @since 4.0 (previous name: remove(Object, Object, Object, Object))
*/
public V removeMultiKey(final Object key1, final Object key2, final Object key3, final Object key4) {
final int hashCode = hash(key1, key2, key3, key4);
final int index = decoratedHashIndex(hashCode);
AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> entry = decorated().data[index];
AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> previous = null;
while (entry != null) {
if (entry.hashCode == hashCode && isEqualKey(entry, key1, key2, key3, key4)) {
final V oldValue = entry.getValue();
decorated().removeMapping(entry, index, previous);
return oldValue;
}
previous = entry;
entry = entry.next;
}
return null;
}
/**
* Removes the specified multi-key from this map.
*
* @param key1 the first key
* @param key2 the second key
* @param key3 the third key
* @param key4 the fourth key
* @param key5 the fifth key
* @return the value mapped to the removed key, null if key not in map
* @since 4.0 (previous name: remove(Object, Object, Object, Object, Object))
*/
public V removeMultiKey(final Object key1, final Object key2, final Object key3,
final Object key4, final Object key5) {
final int hashCode = hash(key1, key2, key3, key4, key5);
final int index = decoratedHashIndex(hashCode);
AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> entry = decorated().data[index];
AbstractHashedMap.HashEntry<MultiKey<? extends K>, V> previous = null;
while (entry != null) {
if (entry.hashCode == hashCode && isEqualKey(entry, key1, key2, key3, key4, key5)) {
final V oldValue = entry.getValue();
decorated().removeMapping(entry, index, previous);
return oldValue;
}
previous = entry;
entry = entry.next;
}
return null;
}
/**
* Serializes this object to an ObjectOutputStream.
*
* @param out the target ObjectOutputStream.
* @throws IOException thrown when an I/O errors occur writing to the target stream.
*/
private void writeObject(final ObjectOutputStream out) throws IOException {
out.defaultWriteObject();
out.writeObject(map);
}
}