/projects/netbeans-7.3/cnd.repository/src/org/netbeans/modules/cnd/repository/util/LongHashMap.java
Java | 931 lines | 479 code | 79 blank | 373 comment | 117 complexity | 951ba56beac8e0acce32d74fea2b1b46 MD5 | raw file
- /*
- * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
- *
- * Copyright 1997-2010 Oracle and/or its affiliates. All rights reserved.
- *
- * Oracle and Java are registered trademarks of Oracle and/or its affiliates.
- * Other names may be trademarks of their respective owners.
- *
- * The contents of this file are subject to the terms of either the GNU
- * General Public License Version 2 only ("GPL") or the Common
- * Development and Distribution License("CDDL") (collectively, the
- * "License"). You may not use this file except in compliance with the
- * License. You can obtain a copy of the License at
- * http://www.netbeans.org/cddl-gplv2.html
- * or nbbuild/licenses/CDDL-GPL-2-CP. See the License for the
- * specific language governing permissions and limitations under the
- * License. When distributing the software, include this License Header
- * Notice in each file and include the License file at
- * nbbuild/licenses/CDDL-GPL-2-CP. Oracle designates this
- * particular file as subject to the "Classpath" exception as provided
- * by Oracle in the GPL Version 2 section of the License file that
- * accompanied this code. If applicable, add the following below the
- * License Header, with the fields enclosed by brackets [] replaced by
- * your own identifying information:
- * "Portions Copyrighted [year] [name of copyright owner]"
- *
- * Contributor(s):
- *
- * The Original Software is NetBeans. The Initial Developer of the Original
- * Software is Sun Microsystems, Inc. Portions Copyright 1997-2007 Sun
- * Microsystems, Inc. All Rights Reserved.
- *
- * If you wish your version of this file to be governed by only the CDDL
- * or only the GPL Version 2, indicate your decision by adding
- * "[Contributor] elects to include this software in this distribution
- * under the [CDDL or GPL Version 2] license." If you do not indicate a
- * single choice of license, a recipient has the option to distribute
- * your version of this file under either the CDDL, the GPL Version 2 or
- * to extend the choice of license to its licensees as provided above.
- * However, if you add GPL Version 2 code and therefore, elected the GPL
- * Version 2 license, then the option applies only if the new code is
- * made subject to such option by the copyright holder.
- */
- package org.netbeans.modules.cnd.repository.util;
- import java.util.AbstractSet;
- import java.util.Collection;
- import java.util.ConcurrentModificationException;
- import java.util.Hashtable;
- import java.util.Iterator;
- import java.util.Map;
- import java.util.NoSuchElementException;
- import java.util.Set;
- import java.util.TreeMap;
- /**
- * Hash table based implementation of the <tt>Map</tt> interface. This
- * implementation provides all of the optional map operations, and permits
- * <tt>null</tt> values and the <tt>null</tt> key. (The <tt>LongHashMap</tt>
- * class is roughly equivalent to <tt>Hashtable</tt>, except that it is
- * unsynchronized and permits nulls.) This class makes no guarantees as to
- * the order of the map; in particular, it does not guarantee that the order
- * will remain constant over time.
- *
- * <p>This implementation provides constant-time performance for the basic
- * operations (<tt>get</tt> and <tt>put</tt>), assuming the hash function
- * disperses the elements properly among the buckets. Iteration over
- * collection views requires time proportional to the "capacity" of the
- * <tt>LongHashMap</tt> instance (the number of buckets) plus its size (the number
- * of key-value mappings). Thus, it's very important not to set the initial
- * capacity too high (or the load factor too low) if iteration performance is
- * important.
- *
- * <p>An instance of <tt>LongHashMap</tt> has two parameters that affect its
- * performance: <i>initial capacity</i> and <i>load factor</i>. The
- * <i>capacity</i> is the number of buckets in the hash table, and the initial
- * capacity is simply the capacity at the time the hash table is created. The
- * <i>load factor</i> is a measure of how full the hash table is allowed to
- * get before its capacity is automatically increased. When the number of
- * entries in the hash table exceeds the product of the load factor and the
- * current capacity, the capacity is roughly doubled by calling the
- * <tt>rehash</tt> method.
- *
- * <p>As a general rule, the default load factor (.75) offers a good tradeoff
- * between time and space costs. Higher values decrease the space overhead
- * but increase the lookup cost (reflected in most of the operations of the
- * <tt>LongHashMap</tt> class, including <tt>get</tt> and <tt>put</tt>). The
- * expected number of entries in the map and its load factor should be taken
- * into account when setting its initial capacity, so as to minimize the
- * number of <tt>rehash</tt> operations. If the initial capacity is greater
- * than the maximum number of entries divided by the load factor, no
- * <tt>rehash</tt> operations will ever occur.
- *
- * <p>If many mappings are to be stored in a <tt>LongHashMap</tt> instance,
- * creating it with a sufficiently large capacity will allow the mappings to
- * be stored more efficiently than letting it perform automatic rehashing as
- * needed to grow the table.
- *
- * <p><b>Note that this implementation is not synchronized.</b> If multiple
- * threads access this map concurrently, and at least one of the threads
- * modifies the map structurally, it <i>must</i> be synchronized externally.
- * (A structural modification is any operation that adds or deletes one or
- * more mappings; merely changing the value associated with a key that an
- * instance already contains is not a structural modification.) This is
- * typically accomplished by synchronizing on some object that naturally
- * encapsulates the map. If no such object exists, the map should be
- * "wrapped" using the <tt>Collections.synchronizedMap</tt> method. This is
- * best done at creation time, to prevent accidental unsynchronized access to
- * the map: <pre> Map m = Collections.synchronizedMap(new LongHashMap(...));
- * </pre>
- *
- * <p>The iterators returned by all of this class's "collection view methods"
- * are <i>fail-fast</i>: if the map is structurally modified at any time after
- * the iterator is created, in any way except through the iterator's own
- * <tt>remove</tt> or <tt>add</tt> methods, the iterator will throw a
- * <tt>ConcurrentModificationException</tt>. Thus, in the face of concurrent
- * modification, the iterator fails quickly and cleanly, rather than risking
- * arbitrary, non-deterministic behavior at an undetermined time in the
- * future.
- *
- * <p>Note that the fail-fast behavior of an iterator cannot be guaranteed
- * as it is, generally speaking, impossible to make any hard guarantees in the
- * presence of unsynchronized concurrent modification. Fail-fast iterators
- * throw <tt>ConcurrentModificationException</tt> on a best-effort basis.
- * Therefore, it would be wrong to write a program that depended on this
- * exception for its correctness: <i>the fail-fast behavior of iterators
- * should be used only to detect bugs.</i>
- *
- * <p>This class is a member of the
- * <a href="{@docRoot}/../guide/collections/index.html">
- * Java Collections Framework</a>.
- *
- * @author Doug Lea
- * @author Josh Bloch
- * @author Arthur van Hoff
- * @author Neal Gafter
- * @version 1.65, 03/03/05
- * @see Object#hashCode()
- * @see Collection
- * @see Map
- * @see TreeMap
- * @see Hashtable
- * @since 1.2
- */
- public class LongHashMap<K> //extends AbstractMap<K>
- //implements Map<K>, Cloneable, Serializable
- {
- public static final long NO_VALUE = Long.MIN_VALUE;
- /**
- * The default initial capacity - MUST be a power of two.
- */
- static final int DEFAULT_INITIAL_CAPACITY = 16;
- /**
- * The maximum capacity, used if a higher value is implicitly specified
- * by either of the constructors with arguments.
- * MUST be a power of two <= 1<<30.
- */
- static final int MAXIMUM_CAPACITY = 1 << 30;
- /**
- * The load factor used when none specified in constructor.
- **/
- static final float DEFAULT_LOAD_FACTOR = 0.75f;
- /**
- * The table, resized as necessary. Length MUST Always be a power of two.
- */
- transient Entry<K>[] table;
- /**
- * The number of key-value mappings contained in this identity hash map.
- */
- transient int size;
- /**
- * The next size value at which to resize (capacity * load factor).
- * @serial
- */
- int threshold;
- /**
- * The load factor for the hash table.
- *
- * @serial
- */
- final float loadFactor;
- /**
- * The number of times this LongHashMap has been structurally modified
- * Structural modifications are those that change the number of mappings in
- * the LongHashMap or otherwise modify its internal structure (e.g.,
- * rehash). This field is used to make iterators on Collection-views of
- * the LongHashMap fail-fast. (See ConcurrentModificationException).
- */
- transient volatile int modCount;
- /**
- * Constructs an empty <tt>LongHashMap</tt> with the specified initial
- * capacity and load factor.
- *
- * @param initialCapacity The initial capacity.
- * @param loadFactor The load factor.
- * @throws IllegalArgumentException if the initial capacity is negative
- * or the load factor is nonpositive.
- */
- public LongHashMap(int initialCapacity, float loadFactor) {
- if (initialCapacity < 0) {
- throw new IllegalArgumentException("Illegal initial capacity: " + // NOI18N
- initialCapacity);
- }
- if (initialCapacity > MAXIMUM_CAPACITY) {
- initialCapacity = MAXIMUM_CAPACITY;
- }
- if (loadFactor <= 0 || Float.isNaN(loadFactor)) {
- throw new IllegalArgumentException("Illegal load factor: " + // NOI18N
- loadFactor);
- }
- // Find a power of 2 >= initialCapacity
- int capacity = 1;
- while (capacity < initialCapacity) {
- capacity <<= 1;
- }
- this.loadFactor = loadFactor;
- threshold = (int) (capacity * loadFactor);
- @SuppressWarnings("unchecked")
- Entry<K>[] ar = new Entry[capacity];
- table = ar;
- init();
- }
- /**
- * Constructs an empty <tt>LongHashMap</tt> with the specified initial
- * capacity and the default load factor (0.75).
- *
- * @param initialCapacity the initial capacity.
- * @throws IllegalArgumentException if the initial capacity is negative.
- */
- public LongHashMap(int initialCapacity) {
- this(initialCapacity, DEFAULT_LOAD_FACTOR);
- }
- /**
- * Constructs an empty <tt>LongHashMap</tt> with the default initial capacity
- * (16) and the default load factor (0.75).
- */
- public LongHashMap() {
- this.loadFactor = DEFAULT_LOAD_FACTOR;
- threshold = (int) (DEFAULT_INITIAL_CAPACITY * DEFAULT_LOAD_FACTOR);
- @SuppressWarnings("unchecked")
- Entry<K>[] ar = new Entry[DEFAULT_INITIAL_CAPACITY];
- table = ar;
- init();
- }
- // internal utilities
- /**
- * Initialization hook for subclasses. This method is called
- * in all constructors and pseudo-constructors (clone, readObject)
- * after LongHashMap has been initialized but before any entries have
- * been inserted. (In the absence of this method, readObject would
- * require explicit knowledge of subclasses.)
- */
- private void init() {
- }
- /**
- * Value representing null keys inside tables.
- */
- static final Object NULL_KEY = new Object();
- /**
- * Returns internal representation for key. Use NULL_KEY if key is null.
- */
- static <T> Object maskNull(T key) {
- return key == null ? NULL_KEY : key;
- }
- /**
- * Returns key represented by specified internal representation.
- */
- static <T> T unmaskNull(T key) {
- return (key == NULL_KEY ? null : key);
- }
- /**
- * Check for equality of non-null reference x and possibly-null y.
- */
- static boolean eq(Object x, Object y) {
- return x == y || x.equals(y);
- }
- /**
- * Returns index for hash code h.
- */
- static int indexFor(int h, int length) {
- return h & (length - 1);
- }
- /**
- * Returns the number of key-value mappings in this map.
- *
- * @return the number of key-value mappings in this map.
- */
- public int size() {
- return size;
- }
- /**
- * Returns <tt>true</tt> if this map contains no key-value mappings.
- *
- * @return <tt>true</tt> if this map contains no key-value mappings.
- */
- public boolean isEmpty() {
- return size == 0;
- }
- /**
- * Returns the value to which the specified key is mapped in this identity
- * hash map, or <tt>null</tt> if the map contains no mapping for this key.
- * A return value of <tt>null</tt> does not <i>necessarily</i> indicate
- * that the map contains no mapping for the key; it is also possible that
- * the map explicitly maps the key to <tt>null</tt>. The
- * <tt>containsKey</tt> method may be used to distinguish these two cases.
- *
- * @param key the key whose associated value is to be returned.
- * @return the value to which this map maps the specified key, or
- * <tt>null</tt> if the map contains no mapping for this key.
- * @see #put(Object, Object)
- */
- public long get(Object key) {
- if (key == null) {
- return getForNullKey();
- }
- int hash = key.hashCode();
- for (Entry<K> e = table[indexFor(hash, table.length)];
- e != null;
- e = e.next) {
- Object k;
- if (e.key.hashCode() == hash && ((k = e.key) == key || key.equals(k))) {
- return e.value;
- }
- }
- return NO_VALUE;
- }
- private long getForNullKey() {
- int hash = NULL_KEY.hashCode();
- int i = indexFor(hash, table.length);
- Entry<K> e = table[i];
- while (true) {
- if (e == null) {
- return NO_VALUE;
- }
- if (e.key == NULL_KEY) {
- return e.value;
- }
- e = e.next;
- }
- }
- /**
- * Returns <tt>true</tt> if this map contains a mapping for the
- * specified key.
- *
- * @param key The key whose presence in this map is to be tested
- * @return <tt>true</tt> if this map contains a mapping for the specified
- * key.
- */
- public boolean containsKey(Object key) {
- Object k = maskNull(key);
- int hash = k.hashCode();
- int i = indexFor(hash, table.length);
- Entry e = table[i];
- while (e != null) {
- if (e.key.hashCode() == hash && eq(k, e.key)) {
- return true;
- }
- e = e.next;
- }
- return false;
- }
- /**
- * Returns the entry associated with the specified key in the
- * LongHashMap. Returns null if the LongHashMap contains no mapping
- * for this key.
- */
- public Entry<K> getEntry(Object key) {
- Object k = maskNull(key);
- int hash = k.hashCode();
- int i = indexFor(hash, table.length);
- Entry<K> e = table[i];
- while (e != null && !(e.key.hashCode() == hash && eq(k, e.key))) {
- e = e.next;
- }
- return e;
- }
- /**
- * Associates the specified value with the specified key in this map.
- * If the map previously contained a mapping for this key, the old
- * value is replaced.
- *
- * @param key key with which the specified value is to be associated.
- * @param value value to be associated with the specified key.
- * @return previous value associated with specified key, or <tt>null</tt>
- * if there was no mapping for key. A <tt>null</tt> return can
- * also indicate that the LongHashMap previously associated
- * <tt>null</tt> with the specified key.
- */
- public long put(K key, long value) {
- if (key == null) {
- return putForNullKey(value);
- }
- int hash = key.hashCode();
- int i = indexFor(hash, table.length);
- for (Entry<K> e = table[i]; e != null; e = e.next) {
- Object k;
- if (e.key.hashCode() == hash && ((k = e.key) == key || key.equals(k))) {
- long oldValue = e.value;
- e.value = value;
- e.recordAccess(this);
- return oldValue;
- }
- }
- modCount++;
- addEntry(key, value, i);
- return NO_VALUE;
- }
- private long putForNullKey(long value) {
- int hash = NULL_KEY.hashCode();
- int i = indexFor(hash, table.length);
- for (Entry<K> e = table[i]; e != null; e = e.next) {
- if (e.key == NULL_KEY) {
- long oldValue = e.value;
- e.value = value;
- e.recordAccess(this);
- return oldValue;
- }
- }
- modCount++;
- @SuppressWarnings("unchecked")
- K nullKey = (K) NULL_KEY;
- addEntry(nullKey, value, i);
- return NO_VALUE;
- }
- /**
- * This method is used instead of put by constructors and
- * pseudoconstructors (clone, readObject). It does not resize the table,
- * check for comodification, etc. It calls createEntry rather than
- * addEntry.
- */
- // private void putForCreate(K key, long value) {
- // K k = maskNull(key);
- // int hash = hash(k.hashCode());
- // int i = indexFor(hash, table.length);
- //
- // /**
- // * Look for preexisting entry for key. This will never happen for
- // * clone or deserialize. It will only happen for construction if the
- // * input Map is a sorted map whose ordering is inconsistent w/ equals.
- // */
- // for (Entry<K> e = table[i]; e != null; e = e.next) {
- // if (e.hash == hash && eq(k, e.key)) {
- // e.value = value;
- // return;
- // }
- // }
- //
- // createEntry(hash, k, value, i);
- // }
- /**
- * Rehashes the contents of this map into a new array with a
- * larger capacity. This method is called automatically when the
- * number of keys in this map reaches its threshold.
- *
- * If current capacity is MAXIMUM_CAPACITY, this method does not
- * resize the map, but sets threshold to Integer.MAX_VALUE.
- * This has the effect of preventing future calls.
- *
- * @param newCapacity the new capacity, MUST be a power of two;
- * must be greater than current capacity unless current
- * capacity is MAXIMUM_CAPACITY (in which case value
- * is irrelevant).
- */
- void resize(int newCapacity) {
- Entry<K>[] oldTable = table;
- int oldCapacity = oldTable.length;
- if (oldCapacity == MAXIMUM_CAPACITY) {
- threshold = Integer.MAX_VALUE;
- return;
- }
- @SuppressWarnings("unchecked")
- Entry<K>[] newTable = new Entry[newCapacity];
- transfer(newTable);
- table = newTable;
- threshold = (int) (newCapacity * loadFactor);
- }
- /**
- * Transfer all entries from current table to newTable.
- */
- void transfer(Entry<K>[] newTable) {
- Entry<K>[] src = table;
- int newCapacity = newTable.length;
- for (int j = 0; j < src.length; j++) {
- Entry<K> e = src[j];
- if (e != null) {
- src[j] = null;
- do {
- Entry<K> next = e.next;
- int i = indexFor(e.key.hashCode(), newCapacity);
- e.next = newTable[i];
- newTable[i] = e;
- e = next;
- } while (e != null);
- }
- }
- }
- public long remove(Object key) {
- Entry<K> e = removeEntryForKey(key);
- return (e == null ? NO_VALUE : e.value);
- }
- /**
- * Removes and returns the entry associated with the specified key
- * in the LongHashMap. Returns null if the LongHashMap contains no mapping
- * for this key.
- */
- Entry<K> removeEntryForKey(Object key) {
- Object k = maskNull(key);
- int hash = k.hashCode();
- int i = indexFor(hash, table.length);
- Entry<K> prev = table[i];
- Entry<K> e = prev;
- while (e != null) {
- Entry<K> next = e.next;
- if (e.key.hashCode() == hash && eq(k, e.key)) {
- modCount++;
- size--;
- if (prev == e) {
- table[i] = next;
- } else {
- prev.next = next;
- }
- e.recordRemoval(this);
- return e;
- }
- prev = e;
- e = next;
- }
- return e;
- }
- /**
- * Special version of remove for EntrySet.
- */
- Entry<K> removeMapping(Object o) {
- if (!(o instanceof Map.Entry)) {
- return null;
- }
- @SuppressWarnings("unchecked")
- LongHashMap.Entry<K> entry = (LongHashMap.Entry<K>) o;
- Object k = maskNull(entry.getKey());
- int hash = k.hashCode();
- int i = indexFor(hash, table.length);
- Entry<K> prev = table[i];
- Entry<K> e = prev;
- while (e != null) {
- Entry<K> next = e.next;
- if (e.key.hashCode() == hash && e.equals(entry)) {
- modCount++;
- size--;
- if (prev == e) {
- table[i] = next;
- } else {
- prev.next = next;
- }
- e.recordRemoval(this);
- return e;
- }
- prev = e;
- e = next;
- }
- return e;
- }
- /**
- * Removes all mappings from this map.
- */
- public void clear() {
- modCount++;
- Entry[] tab = table;
- for (int i = 0; i < tab.length; i++) {
- tab[i] = null;
- }
- size = 0;
- }
- /**
- * Returns <tt>true</tt> if this map maps one or more keys to the
- * specified value.
- *
- * @param value value whose presence in this map is to be tested.
- * @return <tt>true</tt> if this map maps one or more keys to the
- * specified value.
- */
- public boolean containsValue(Object value) {
- if (value == null) {
- return containsNullValue();
- }
- Entry[] tab = table;
- for (int i = 0; i < tab.length; i++) {
- for (Entry e = tab[i]; e != null; e = e.next) {
- if (value.equals(e.value)) {
- return true;
- }
- }
- }
- return false;
- }
- /**
- * Special-case code for containsValue with null argument
- **/
- private boolean containsNullValue() {
- Entry[] tab = table;
- for (int i = 0; i < tab.length; i++) {
- for (Entry e = tab[i]; e != null; e = e.next) {
- if (e.value == NO_VALUE) {
- return true;
- }
- }
- }
- return false;
- }
- public static class Entry<K> /*implements Map.Entry<K>*/ {
- final K key;
- long value;
- Entry<K> next;
- /**
- * Create new entry.
- */
- Entry(K k, long v, Entry<K> n) {
- value = v;
- next = n;
- key = k;
- }
- public K getKey() {
- return LongHashMap.<K>unmaskNull(key);
- }
- public long getValue() {
- return value;
- }
- public long setValue(long newValue) {
- long oldValue = value;
- value = newValue;
- return oldValue;
- }
- @Override
- public boolean equals(Object o) {
- if (!(o instanceof Entry)) {
- return false;
- }
- Entry e = (Entry) o;
- Object k1 = getKey();
- Object k2 = e.getKey();
- if (k1 == k2 || (k1 != null && k1.equals(k2))) {
- long v1 = getValue();
- long v2 = e.getValue();
- if (v1 == v2) {
- return true;
- }
- }
- return false;
- }
- @Override
- public int hashCode() {
- return (int) (value ^ (value >>> 32));
- }
- @Override
- public String toString() {
- return getKey() + "=" + getValue(); // NOI18N
- }
- /**
- * This method is invoked whenever the value in an entry is
- * overwritten by an invocation of put(k,v) for a key k that's already
- * in the LongHashMap.
- */
- void recordAccess(LongHashMap<K> m) {
- }
- /**
- * This method is invoked whenever the entry is
- * removed from the table.
- */
- void recordRemoval(LongHashMap<K> m) {
- }
- }
- /**
- * Add a new entry with the specified key, value and hash code to
- * the specified bucket. It is the responsibility of this
- * method to resize the table if appropriate.
- *
- * Subclass overrides this to alter the behavior of put method.
- */
- void addEntry(K key, long value, int bucketIndex) {
- Entry<K> e = table[bucketIndex];
- table[bucketIndex] = new Entry<K>(key, value, e);
- if (size++ >= threshold) {
- resize(2 * table.length);
- }
- }
- private abstract class HashIterator<E> implements Iterator<E> {
- Entry<K> next; // next entry to return
- int expectedModCount; // For fast-fail
- int index; // current slot
- Entry<K> current; // current entry
- HashIterator() {
- expectedModCount = modCount;
- Entry<K>[] t = table;
- int i = t.length;
- Entry<K> n = null;
- if (size != 0) { // advance to first entry
- while (i > 0 && (n = t[--i]) == null) {
- }
- }
- next = n;
- index = i;
- }
- @Override
- public boolean hasNext() {
- return next != null;
- }
- Entry<K> nextEntry() {
- if (modCount != expectedModCount) {
- throw new ConcurrentModificationException();
- }
- Entry<K> e = next;
- if (e == null) {
- throw new NoSuchElementException();
- }
- Entry<K> n = e.next;
- Entry<K>[] t = table;
- int i = index;
- while (n == null && i > 0) {
- n = t[--i];
- }
- index = i;
- next = n;
- return current = e;
- }
- @Override
- public void remove() {
- if (current == null) {
- throw new IllegalStateException();
- }
- if (modCount != expectedModCount) {
- throw new ConcurrentModificationException();
- }
- Object k = current.key;
- current = null;
- LongHashMap.this.removeEntryForKey(k);
- expectedModCount = modCount;
- }
- }
- private class KeyIterator extends HashIterator<K> {
- @Override
- public K next() {
- return nextEntry().getKey();
- }
- }
- private class EntryIterator extends HashIterator<LongHashMap.Entry<K>> {
- @Override
- public LongHashMap.Entry<K> next() {
- return nextEntry();
- }
- }
- // Subclass overrides these to alter behavior of views' iterator() method
- Iterator<K> newKeyIterator() {
- return new KeyIterator();
- }
- Iterator<LongHashMap.Entry<K>> newEntryIterator() {
- return new EntryIterator();
- }
- // Views
- private transient Set<LongHashMap.Entry<K>> entrySet = null;
- /**
- * Each of these fields are initialized to contain an instance of the
- * appropriate view the first time this view is requested. The views are
- * stateless, so there's no reason to create more than one of each.
- */
- transient volatile Set<K> keySet = null;
- /**
- * Returns a set view of the keys contained in this map. The set is
- * backed by the map, so changes to the map are reflected in the set, and
- * vice-versa. The set supports element removal, which removes the
- * corresponding mapping from this map, via the <tt>Iterator.remove</tt>,
- * <tt>Set.remove</tt>, <tt>removeAll</tt>, <tt>retainAll</tt>, and
- * <tt>clear</tt> operations. It does not support the <tt>add</tt> or
- * <tt>addAll</tt> operations.
- *
- * @return a set view of the keys contained in this map.
- */
- public Set<K> keySet() {
- Set<K> ks = keySet;
- return (ks != null ? ks : (keySet = new KeySet()));
- }
- private class KeySet extends AbstractSet<K> {
- @Override
- public Iterator<K> iterator() {
- return newKeyIterator();
- }
- @Override
- public int size() {
- return size;
- }
- @Override
- public boolean contains(Object o) {
- return containsKey(o);
- }
- @Override
- public boolean remove(Object o) {
- return LongHashMap.this.removeEntryForKey(o) != null;
- }
- @Override
- public void clear() {
- LongHashMap.this.clear();
- }
- }
- /**
- * Returns a collection view of the mappings contained in this map. Each
- * element in the returned collection is a <tt>Map.Entry</tt>. The
- * collection is backed by the map, so changes to the map are reflected in
- * the collection, and vice-versa. The collection supports element
- * removal, which removes the corresponding mapping from the map, via the
- * <tt>Iterator.remove</tt>, <tt>Collection.remove</tt>,
- * <tt>removeAll</tt>, <tt>retainAll</tt>, and <tt>clear</tt> operations.
- * It does not support the <tt>add</tt> or <tt>addAll</tt> operations.
- *
- * @return a collection view of the mappings contained in this map.
- * @see Map.Entry
- */
- public Set<LongHashMap.Entry<K>> entrySet() {
- Set<LongHashMap.Entry<K>> es = entrySet;
- return (es != null ? es : (entrySet = new EntrySet()));
- }
- private class EntrySet extends AbstractSet<LongHashMap.Entry<K>> {
- @Override
- public Iterator<LongHashMap.Entry<K>> iterator() {
- return newEntryIterator();
- }
- @Override
- public boolean contains(Object o) {
- if (!(o instanceof Map.Entry)) {
- return false;
- }
- @SuppressWarnings("unchecked")
- LongHashMap.Entry<K> e = (LongHashMap.Entry<K>) o;
- Entry<K> candidate = getEntry(e.getKey());
- return candidate != null && candidate.equals(e);
- }
- @Override
- public boolean remove(Object o) {
- return removeMapping(o) != null;
- }
- @Override
- public int size() {
- return size;
- }
- @Override
- public void clear() {
- LongHashMap.this.clear();
- }
- }
- // These methods are used when serializing HashSets
- int capacity() {
- return table.length;
- }
- float loadFactor() {
- return loadFactor;
- }
- }