- /*
- * Copyright 2003-2004 The Apache Software Foundation
- *
- * Licensed 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.collections.map;
-
- import java.io.IOException;
- import java.io.ObjectInputStream;
- import java.io.ObjectOutputStream;
- import java.io.Serializable;
- import java.util.AbstractCollection;
- import java.util.AbstractSet;
- import java.util.Collection;
- import java.util.Iterator;
- import java.util.Map;
- import java.util.NoSuchElementException;
- import java.util.Set;
-
- import org.apache.commons.collections.IterableMap;
- import org.apache.commons.collections.MapIterator;
- import org.apache.commons.collections.ResettableIterator;
- import org.apache.commons.collections.iterators.EmptyIterator;
- import org.apache.commons.collections.iterators.EmptyMapIterator;
-
- /**
- * A <code>Map</code> implementation that stores data in simple fields until
- * the size is greater than 3.
- * <p>
- * This map is designed for performance and can outstrip HashMap.
- * It also has good garbage collection characteristics.
- * <ul>
- * <li>Optimised for operation at size 3 or less.
- * <li>Still works well once size 3 exceeded.
- * <li>Gets at size 3 or less are about 0-10% faster than HashMap,
- * <li>Puts at size 3 or less are over 4 times faster than HashMap.
- * <li>Performance 5% slower than HashMap once size 3 exceeded once.
- * </ul>
- * The design uses two distinct modes of operation - flat and delegate.
- * While the map is size 3 or less, operations map straight onto fields using
- * switch statements. Once size 4 is reached, the map switches to delegate mode
- * and only switches back when cleared. In delegate mode, all operations are
- * forwarded straight to a HashMap resulting in the 5% performance loss.
- * <p>
- * The performance gains on puts are due to not needing to create a Map Entry
- * object. This is a large saving not only in performance but in garbage collection.
- * <p>
- * Whilst in flat mode this map is also easy for the garbage collector to dispatch.
- * This is because it contains no complex objects or arrays which slow the progress.
- * <p>
- * Do not use <code>Flat3Map</code> if the size is likely to grow beyond 3.
- *
- * @since Commons Collections 3.0
- * @version $Revision: 1.18 $ $Date: 2004/05/26 21:56:05 $
- *
- * @author Stephen Colebourne
- */
- public class Flat3Map implements IterableMap, Serializable, Cloneable {
-
- /** Serialization version */
- private static final long serialVersionUID = -6701087419741928296L;
-
- /** The size of the map, used while in flat mode */
- private transient int size;
- /** Hash, used while in flat mode */
- private transient int hash1;
- /** Hash, used while in flat mode */
- private transient int hash2;
- /** Hash, used while in flat mode */
- private transient int hash3;
- /** Key, used while in flat mode */
- private transient Object key1;
- /** Key, used while in flat mode */
- private transient Object key2;
- /** Key, used while in flat mode */
- private transient Object key3;
- /** Value, used while in flat mode */
- private transient Object value1;
- /** Value, used while in flat mode */
- private transient Object value2;
- /** Value, used while in flat mode */
- private transient Object value3;
- /** Map, used while in delegate mode */
- private transient AbstractHashedMap delegateMap;
-
- /**
- * Constructor.
- */
- public Flat3Map() {
- super();
- }
-
- /**
- * Constructor copying elements from another map.
- *
- * @param map the map to copy
- * @throws NullPointerException if the map is null
- */
- public Flat3Map(Map map) {
- super();
- putAll(map);
- }
-
- //-----------------------------------------------------------------------
- /**
- * Gets the value mapped to the key specified.
- *
- * @param key the key
- * @return the mapped value, null if no match
- */
- public Object get(Object key) {
- if (delegateMap != null) {
- return delegateMap.get(key);
- }
- if (key == null) {
- switch (size) {
- // drop through
- case 3:
- if (key3 == null) return value3;
- case 2:
- if (key2 == null) return value2;
- case 1:
- if (key1 == null) return value1;
- }
- } else {
- if (size > 0) {
- int hashCode = key.hashCode();
- switch (size) {
- // drop through
- case 3:
- if (hash3 == hashCode && key.equals(key3)) return value3;
- case 2:
- if (hash2 == hashCode && key.equals(key2)) return value2;
- case 1:
- if (hash1 == hashCode && key.equals(key1)) return value1;
- }
- }
- }
- return null;
- }
-
- /**
- * Gets the size of the map.
- *
- * @return the size
- */
- public int size() {
- if (delegateMap != null) {
- return delegateMap.size();
- }
- return size;
- }
-
- /**
- * Checks whether the map is currently empty.
- *
- * @return true if the map is currently size zero
- */
- public boolean isEmpty() {
- return (size() == 0);
- }
-
- //-----------------------------------------------------------------------
- /**
- * Checks whether the map contains the specified key.
- *
- * @param key the key to search for
- * @return true if the map contains the key
- */
- public boolean containsKey(Object key) {
- if (delegateMap != null) {
- return delegateMap.containsKey(key);
- }
- if (key == null) {
- switch (size) { // drop through
- case 3:
- if (key3 == null) return true;
- case 2:
- if (key2 == null) return true;
- case 1:
- if (key1 == null) return true;
- }
- } else {
- if (size > 0) {
- int hashCode = key.hashCode();
- switch (size) { // drop through
- case 3:
- if (hash3 == hashCode && key.equals(key3)) return true;
- case 2:
- if (hash2 == hashCode && key.equals(key2)) return true;
- case 1:
- if (hash1 == hashCode && key.equals(key1)) return true;
- }
- }
- }
- return false;
- }
-
- /**
- * Checks whether the map contains the specified value.
- *
- * @param value the value to search for
- * @return true if the map contains the key
- */
- public boolean containsValue(Object value) {
- if (delegateMap != null) {
- return delegateMap.containsValue(value);
- }
- if (value == null) { // drop through
- switch (size) {
- case 3:
- if (value3 == null) return true;
- case 2:
- if (value2 == null) return true;
- case 1:
- if (value1 == null) return true;
- }
- } else {
- switch (size) { // drop through
- case 3:
- if (value.equals(value3)) return true;
- case 2:
- if (value.equals(value2)) return true;
- case 1:
- if (value.equals(value1)) return true;
- }
- }
- return false;
- }
-
- //-----------------------------------------------------------------------
- /**
- * Puts a key-value mapping into this map.
- *
- * @param key the key to add
- * @param value the value to add
- * @return the value previously mapped to this key, null if none
- */
- public Object put(Object key, Object value) {
- if (delegateMap != null) {
- return delegateMap.put(key, value);
- }
- // change existing mapping
- if (key == null) {
- switch (size) { // drop through
- case 3:
- if (key3 == null) {
- Object old = value3;
- value3 = value;
- return old;
- }
- case 2:
- if (key2 == null) {
- Object old = value2;
- value2 = value;
- return old;
- }
- case 1:
- if (key1 == null) {
- Object old = value1;
- value1 = value;
- return old;
- }
- }
- } else {
- if (size > 0) {
- int hashCode = key.hashCode();
- switch (size) { // drop through
- case 3:
- if (hash3 == hashCode && key.equals(key3)) {
- Object old = value3;
- value3 = value;
- return old;
- }
- case 2:
- if (hash2 == hashCode && key.equals(key2)) {
- Object old = value2;
- value2 = value;
- return old;
- }
- case 1:
- if (hash1 == hashCode && key.equals(key1)) {
- Object old = value1;
- value1 = value;
- return old;
- }
- }
- }
- }
-
- // add new mapping
- switch (size) {
- default:
- convertToMap();
- delegateMap.put(key, value);
- return null;
- case 2:
- hash3 = (key == null ? 0 : key.hashCode());
- key3 = key;
- value3 = value;
- break;
- case 1:
- hash2 = (key == null ? 0 : key.hashCode());
- key2 = key;
- value2 = value;
- break;
- case 0:
- hash1 = (key == null ? 0 : key.hashCode());
- key1 = key;
- value1 = value;
- break;
- }
- size++;
- return null;
- }
-
- /**
- * Puts all the values from the specified map into this map.
- *
- * @param map the map to add
- * @throws NullPointerException if the map is null
- */
- public void putAll(Map map) {
- int size = map.size();
- if (size == 0) {
- return;
- }
- if (delegateMap != null) {
- delegateMap.putAll(map);
- return;
- }
- if (size < 4) {
- for (Iterator it = map.entrySet().iterator(); it.hasNext();) {
- Map.Entry entry = (Map.Entry) it.next();
- put(entry.getKey(), entry.getValue());
- }
- } else {
- convertToMap();
- delegateMap.putAll(map);
- }
- }
-
- /**
- * Converts the flat map data to a map.
- */
- private void convertToMap() {
- delegateMap = createDelegateMap();
- switch (size) { // drop through
- case 3:
- delegateMap.put(key3, value3);
- case 2:
- delegateMap.put(key2, value2);
- case 1:
- delegateMap.put(key1, value1);
- }
-
- size = 0;
- hash1 = hash2 = hash3 = 0;
- key1 = key2 = key3 = null;
- value1 = value2 = value3 = null;
- }
-
- /**
- * Create an instance of the map used for storage when in delegation mode.
- * <p>
- * This can be overridden by subclasses to provide a different map implementation.
- * Not every AbstractHashedMap is suitable, identity and reference based maps
- * would be poor choices.
- *
- * @return a new AbstractHashedMap or subclass
- * @since Commons Collections 3.1
- */
- protected AbstractHashedMap createDelegateMap() {
- return new HashedMap();
- }
-
- /**
- * Removes the specified mapping from this map.
- *
- * @param key the mapping to remove
- * @return the value mapped to the removed key, null if key not in map
- */
- public Object remove(Object key) {
- if (delegateMap != null) {
- return delegateMap.remove(key);
- }
- if (size == 0) {
- return null;
- }
- if (key == null) {
- switch (size) { // drop through
- case 3:
- if (key3 == null) {
- Object old = value3;
- hash3 = 0;
- key3 = null;
- value3 = null;
- size = 2;
- return old;
- }
- if (key2 == null) {
- Object old = value3;
- hash2 = hash3;
- key2 = key3;
- value2 = value3;
- hash3 = 0;
- key3 = null;
- value3 = null;
- size = 2;
- return old;
- }
- if (key1 == null) {
- Object old = value3;
- hash1 = hash3;
- key1 = key3;
- value1 = value3;
- hash3 = 0;
- key3 = null;
- value3 = null;
- size = 2;
- return old;
- }
- return null;
- case 2:
- if (key2 == null) {
- Object old = value2;
- hash2 = 0;
- key2 = null;
- value2 = null;
- size = 1;
- return old;
- }
- if (key1 == null) {
- Object old = value2;
- hash1 = hash2;
- key1 = key2;
- value1 = value2;
- hash2 = 0;
- key2 = null;
- value2 = null;
- size = 1;
- return old;
- }
- return null;
- case 1:
- if (key1 == null) {
- Object old = value1;
- hash1 = 0;
- key1 = null;
- value1 = null;
- size = 0;
- return old;
- }
- }
- } else {
- if (size > 0) {
- int hashCode = key.hashCode();
- switch (size) { // drop through
- case 3:
- if (hash3 == hashCode && key.equals(key3)) {
- Object old = value3;
- hash3 = 0;
- key3 = null;
- value3 = null;
- size = 2;
- return old;
- }
- if (hash2 == hashCode && key.equals(key2)) {
- Object old = value3;
- hash2 = hash3;
- key2 = key3;
- value2 = value3;
- hash3 = 0;
- key3 = null;
- value3 = null;
- size = 2;
- return old;
- }
- if (hash1 == hashCode && key.equals(key1)) {
- Object old = value3;
- hash1 = hash3;
- key1 = key3;
- value1 = value3;
- hash3 = 0;
- key3 = null;
- value3 = null;
- size = 2;
- return old;
- }
- return null;
- case 2:
- if (hash2 == hashCode && key.equals(key2)) {
- Object old = value2;
- hash2 = 0;
- key2 = null;
- value2 = null;
- size = 1;
- return old;
- }
- if (hash1 == hashCode && key.equals(key1)) {
- Object old = value2;
- hash1 = hash2;
- key1 = key2;
- value1 = value2;
- hash2 = 0;
- key2 = null;
- value2 = null;
- size = 1;
- return old;
- }
- return null;
- case 1:
- if (hash1 == hashCode && key.equals(key1)) {
- Object old = value1;
- hash1 = 0;
- key1 = null;
- value1 = null;
- size = 0;
- return old;
- }
- }
- }
- }
- return null;
- }
-
- /**
- * Clears the map, resetting the size to zero and nullifying references
- * to avoid garbage collection issues.
- */
- public void clear() {
- if (delegateMap != null) {
- delegateMap.clear(); // should aid gc
- delegateMap = null; // switch back to flat mode
- } else {
- size = 0;
- hash1 = hash2 = hash3 = 0;
- key1 = key2 = key3 = null;
- value1 = value2 = value3 = null;
- }
- }
-
- //-----------------------------------------------------------------------
- /**
- * Gets an iterator over the map.
- * Changes made to the iterator affect this map.
- * <p>
- * A MapIterator returns the keys in the map. It also provides convenient
- * methods to get the key and value, and set the value.
- * It avoids the need to create an entrySet/keySet/values object.
- * It also avoids creating the Map Entry object.
- *
- * @return the map iterator
- */
- public MapIterator mapIterator() {
- if (delegateMap != null) {
- return delegateMap.mapIterator();
- }
- if (size == 0) {
- return EmptyMapIterator.INSTANCE;
- }
- return new FlatMapIterator(this);
- }
-
- /**
- * FlatMapIterator
- */
- static class FlatMapIterator implements MapIterator, ResettableIterator {
- private final Flat3Map parent;
- private int nextIndex = 0;
- private boolean canRemove = false;
-
- FlatMapIterator(Flat3Map parent) {
- super();
- this.parent = parent;
- }
-
- public boolean hasNext() {
- return (nextIndex < parent.size);
- }
-
- public Object next() {
- if (hasNext() == false) {
- throw new NoSuchElementException(AbstractHashedMap.NO_NEXT_ENTRY);
- }
- canRemove = true;
- nextIndex++;
- return getKey();
- }
-
- public void remove() {
- if (canRemove == false) {
- throw new IllegalStateException(AbstractHashedMap.REMOVE_INVALID);
- }
- parent.remove(getKey());
- nextIndex--;
- canRemove = false;
- }
-
- public Object getKey() {
- if (canRemove == false) {
- throw new IllegalStateException(AbstractHashedMap.GETKEY_INVALID);
- }
- switch (nextIndex) {
- case 3:
- return parent.key3;
- case 2:
- return parent.key2;
- case 1:
- return parent.key1;
- }
- throw new IllegalStateException("Invalid map index");
- }
-
- public Object getValue() {
- if (canRemove == false) {
- throw new IllegalStateException(AbstractHashedMap.GETVALUE_INVALID);
- }
- switch (nextIndex) {
- case 3:
- return parent.value3;
- case 2:
- return parent.value2;
- case 1:
- return parent.value1;
- }
- throw new IllegalStateException("Invalid map index");
- }
-
- public Object setValue(Object value) {
- if (canRemove == false) {
- throw new IllegalStateException(AbstractHashedMap.SETVALUE_INVALID);
- }
- Object old = getValue();
- switch (nextIndex) {
- case 3:
- parent.value3 = value;
- case 2:
- parent.value2 = value;
- case 1:
- parent.value1 = value;
- }
- return old;
- }
-
- public void reset() {
- nextIndex = 0;
- canRemove = false;
- }
-
- public String toString() {
- if (canRemove) {
- return "Iterator[" + getKey() + "=" + getValue() + "]";
- } else {
- return "Iterator[]";
- }
- }
- }
-
- /**
- * Gets the entrySet view of the map.
- * Changes made to the view affect this map.
- * The Map Entry is not an independent object and changes as the
- * iterator progresses.
- * To simply iterate through the entries, use {@link #mapIterator()}.
- *
- * @return the entrySet view
- */
- public Set entrySet() {
- if (delegateMap != null) {
- return delegateMap.entrySet();
- }
- return new EntrySet(this);
- }
-
- /**
- * EntrySet
- */
- static class EntrySet extends AbstractSet {
- private final Flat3Map parent;
-
- EntrySet(Flat3Map parent) {
- super();
- this.parent = parent;
- }
-
- public int size() {
- return parent.size();
- }
-
- public void clear() {
- parent.clear();
- }
-
- public boolean remove(Object obj) {
- if (obj instanceof Map.Entry == false) {
- return false;
- }
- Map.Entry entry = (Map.Entry) obj;
- Object key = entry.getKey();
- boolean result = parent.containsKey(key);
- parent.remove(key);
- return result;
- }
-
- public Iterator iterator() {
- if (parent.delegateMap != null) {
- return parent.delegateMap.entrySet().iterator();
- }
- if (parent.size() == 0) {
- return EmptyIterator.INSTANCE;
- }
- return new EntrySetIterator(parent);
- }
- }
-
- /**
- * EntrySetIterator and MapEntry
- */
- static class EntrySetIterator implements Iterator, Map.Entry {
- private final Flat3Map parent;
- private int nextIndex = 0;
- private boolean canRemove = false;
-
- EntrySetIterator(Flat3Map parent) {
- super();
- this.parent = parent;
- }
-
- public boolean hasNext() {
- return (nextIndex < parent.size);
- }
-
- public Object next() {
- if (hasNext() == false) {
- throw new NoSuchElementException(AbstractHashedMap.NO_NEXT_ENTRY);
- }
- canRemove = true;
- nextIndex++;
- return this;
- }
-
- public void remove() {
- if (canRemove == false) {
- throw new IllegalStateException(AbstractHashedMap.REMOVE_INVALID);
- }
- parent.remove(getKey());
- nextIndex--;
- canRemove = false;
- }
-
- public Object getKey() {
- if (canRemove == false) {
- throw new IllegalStateException(AbstractHashedMap.GETKEY_INVALID);
- }
- switch (nextIndex) {
- case 3:
- return parent.key3;
- case 2:
- return parent.key2;
- case 1:
- return parent.key1;
- }
- throw new IllegalStateException("Invalid map index");
- }
-
- public Object getValue() {
- if (canRemove == false) {
- throw new IllegalStateException(AbstractHashedMap.GETVALUE_INVALID);
- }
- switch (nextIndex) {
- case 3:
- return parent.value3;
- case 2:
- return parent.value2;
- case 1:
- return parent.value1;
- }
- throw new IllegalStateException("Invalid map index");
- }
-
- public Object setValue(Object value) {
- if (canRemove == false) {
- throw new IllegalStateException(AbstractHashedMap.SETVALUE_INVALID);
- }
- Object old = getValue();
- switch (nextIndex) {
- case 3:
- parent.value3 = value;
- case 2:
- parent.value2 = value;
- case 1:
- parent.value1 = value;
- }
- return old;
- }
-
- public boolean equals(Object obj) {
- if (canRemove == false) {
- return false;
- }
- if (obj instanceof Map.Entry == false) {
- return false;
- }
- Map.Entry other = (Map.Entry) obj;
- Object key = getKey();
- Object value = getValue();
- return (key == null ? other.getKey() == null : key.equals(other.getKey())) &&
- (value == null ? other.getValue() == null : value.equals(other.getValue()));
- }
-
- public int hashCode() {
- if (canRemove == false) {
- return 0;
- }
- Object key = getKey();
- Object value = getValue();
- return (key == null ? 0 : key.hashCode()) ^
- (value == null ? 0 : value.hashCode());
- }
-
- public String toString() {
- if (canRemove) {
- return getKey() + "=" + getValue();
- } else {
- return "";
- }
- }
- }
-
- /**
- * Gets the keySet view of the map.
- * Changes made to the view affect this map.
- * To simply iterate through the keys, use {@link #mapIterator()}.
- *
- * @return the keySet view
- */
- public Set keySet() {
- if (delegateMap != null) {
- return delegateMap.keySet();
- }
- return new KeySet(this);
- }
-
- /**
- * KeySet
- */
- static class KeySet extends AbstractSet {
- private final Flat3Map parent;
-
- KeySet(Flat3Map parent) {
- super();
- this.parent = parent;
- }
-
- public int size() {
- return parent.size();
- }
-
- public void clear() {
- parent.clear();
- }
-
- public boolean contains(Object key) {
- return parent.containsKey(key);
- }
-
- public boolean remove(Object key) {
- boolean result = parent.containsKey(key);
- parent.remove(key);
- return result;
- }
-
- public Iterator iterator() {
- if (parent.delegateMap != null) {
- return parent.delegateMap.keySet().iterator();
- }
- if (parent.size() == 0) {
- return EmptyIterator.INSTANCE;
- }
- return new KeySetIterator(parent);
- }
- }
-
- /**
- * KeySetIterator
- */
- static class KeySetIterator extends EntrySetIterator {
-
- KeySetIterator(Flat3Map parent) {
- super(parent);
- }
-
- public Object next() {
- super.next();
- return getKey();
- }
- }
-
- /**
- * Gets the values view of the map.
- * Changes made to the view affect this map.
- * To simply iterate through the values, use {@link #mapIterator()}.
- *
- * @return the values view
- */
- public Collection values() {
- if (delegateMap != null) {
- return delegateMap.values();
- }
- return new Values(this);
- }
-
- /**
- * Values
- */
- static class Values extends AbstractCollection {
- private final Flat3Map parent;
-
- Values(Flat3Map parent) {
- super();
- this.parent = parent;
- }
-
- public int size() {
- return parent.size();
- }
-
- public void clear() {
- parent.clear();
- }
-
- public boolean contains(Object value) {
- return parent.containsValue(value);
- }
-
- public Iterator iterator() {
- if (parent.delegateMap != null) {
- return parent.delegateMap.values().iterator();
- }
- if (parent.size() == 0) {
- return EmptyIterator.INSTANCE;
- }
- return new ValuesIterator(parent);
- }
- }
-
- /**
- * ValuesIterator
- */
- static class ValuesIterator extends EntrySetIterator {
-
- ValuesIterator(Flat3Map parent) {
- super(parent);
- }
-
- public Object next() {
- super.next();
- return getValue();
- }
- }
-
- //-----------------------------------------------------------------------
- /**
- * Write the map out using a custom routine.
- */
- private void writeObject(ObjectOutputStream out) throws IOException {
- out.defaultWriteObject();
- out.writeInt(size());
- for (MapIterator it = mapIterator(); it.hasNext();) {
- out.writeObject(it.next()); // key
- out.writeObject(it.getValue()); // value
- }
- }
-
- /**
- * Read the map in using a custom routine.
- */
- private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {
- in.defaultReadObject();
- int count = in.readInt();
- if (count > 3) {
- delegateMap = createDelegateMap();
- }
- for (int i = count; i > 0; i--) {
- put(in.readObject(), in.readObject());
- }
- }
-
- //-----------------------------------------------------------------------
- /**
- * Clones the map without cloning the keys or values.
- *
- * @return a shallow clone
- * @since Commons Collections 3.1
- */
- public Object clone() {
- try {
- Flat3Map cloned = (Flat3Map) super.clone();
- if (cloned.delegateMap != null) {
- cloned.delegateMap = (HashedMap) cloned.delegateMap.clone();
- }
- return cloned;
- } catch (CloneNotSupportedException ex) {
- throw new InternalError();
- }
- }
-
- /**
- * Compares this map with another.
- *
- * @param obj the object to compare to
- * @return true if equal
- */
- public boolean equals(Object obj) {
- if (obj == this) {
- return true;
- }
- if (delegateMap != null) {
- return delegateMap.equals(obj);
- }
- if (obj instanceof Map == false) {
- return false;
- }
- Map other = (Map) obj;
- if (size != other.size()) {
- return false;
- }
- if (size > 0) {
- Object otherValue = null;
- switch (size) { // drop through
- case 3:
- if (other.containsKey(key3) == false) {
- otherValue = other.get(key3);
- if (value3 == null ? otherValue != null : !value3.equals(otherValue)) {
- return false;
- }
- }
- case 2:
- if (other.containsKey(key2) == false) {
- otherValue = other.get(key2);
- if (value2 == null ? otherValue != null : !value2.equals(otherValue)) {
- return false;
- }
- }
- case 1:
- if (other.containsKey(key1) == false) {
- otherValue = other.get(key1);
- if (value1 == null ? otherValue != null : !value1.equals(otherValue)) {
- return false;
- }
- }
- }
- }
- return true;
- }
-
- /**
- * Gets the standard Map hashCode.
- *
- * @return the hash code defined in the Map interface
- */
- public int hashCode() {
- if (delegateMap != null) {
- return delegateMap.hashCode();
- }
- int total = 0;
- switch (size) { // drop through
- case 3:
- total += (hash3 ^ (value3 == null ? 0 : value3.hashCode()));
- case 2:
- total += (hash2 ^ (value2 == null ? 0 : value2.hashCode()));
- case 1:
- total += (hash1 ^ (value1 == null ? 0 : value1.hashCode()));
- }
- return total;
- }
-
- /**
- * Gets the map as a String.
- *
- * @return a string version of the map
- */
- public String toString() {
- if (delegateMap != null) {
- return delegateMap.toString();
- }
- if (size == 0) {
- return "{}";
- }
- StringBuffer buf = new StringBuffer(128);
- buf.append('{');
- switch (size) { // drop through
- case 3:
- buf.append((key3 == this ? "(this Map)" : key3));
- buf.append('=');
- buf.append((value3 == this ? "(this Map)" : value3));
- buf.append(',');
- case 2:
- buf.append((key2 == this ? "(this Map)" : key2));
- buf.append('=');
- buf.append((value2 == this ? "(this Map)" : value2));
- buf.append(',');
- case 1:
- buf.append((key1 == this ? "(this Map)" : key1));
- buf.append('=');
- buf.append((value1 == this ? "(this Map)" : value1));
- }
- buf.append('}');
- return buf.toString();
- }
-
- }