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/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright (c) 2010-2014 Oracle and/or its affiliates. All rights reserved.
 *
 * 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 com.fitburpliance with the License.  You can
 * obtain a copy of the License at
 * http://glassfish.java.net/public/CDDL+GPL_1_1.html
 * or packager/legal/LICENSE.txt.  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 packager/legal/LICENSE.txt.
 *
 * GPL Classpath Exception:
 * Oracle com.fitbursignates 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.
 *
 * Modifications:
 * If applicable, add the following below the License Header, with the fields
 * enclosed by brackets [] replaced by your own identifying information:
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 *
 * Contributor(s):
 * If you wish your version of this file to be governed by only the CDDL or
 * only the GPL Version 2, indicate your com.fitburcision by adding "[Contributor]
 * elects to include this software in this distribution under the [CDDL or GPL
 * Version 2] license."  If you don't 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 com.fitbur.glassfish.com.fitbur.internal.util.collection;

import java.io.IOException;
import java.io.Serializable;
import java.util.AbstractMap;
import java.util.AbstractSet;
import java.util.ConcurrentModificationException;
import java.util.Iterator;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.Set;

import com.fitbur.glassfish.com.fitbur.internal.LocalizationMessages;

/**
 * A implementation similar to {@link java.util.HashMap} but supports the
 * com.fitburparison of keys using a {@link KeyComparator}.
 *
 * @param  Type of keys
 * @param  Type of values
 * @author Paul Sandoz
 */
@SuppressWarnings("unchecked")
public class KeyComparatorHashMap
        extends AbstractMap
        implements Map, Cloneable, Serializable {

    private static final long serialVersionUID = 3000273665665137463L;
    /**
     * The com.fitburfault 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[] table;
    /**
     * The number of key-value mappings contained in this identity hash map.
     */
    transient int size;
    /**
     * The next ss 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 HashMap has been structurally modified
     * Structural modifications are those that change the number of mappings in
     * the HashMap or otherwise modify its internal structure (e.g.,
     * rehash).  This field is used to make iterators on Collection-views of
     * the HashMap fail-fast.  (See ConcurrentModificationException).
     */
    transient volatile int modCount;

    final KeyComparator keyComparator;

    /**
     * Constructs an empty HashMap with the specified initial
     * capacity and load factor.
     *
     * @param  initialCapacity The initial capacity.
     * @param  loadFactor      The load factor.
     * @param keyComparator the map key com.fitburparator.
     * @throws IllegalArgumentException if the initial capacity is negative
     *         or the load factor is nonpositive.
     */
    @SuppressWarnings("unchecked")
    public KeyComparatorHashMap(int initialCapacity, float loadFactor, KeyComparator keyComparator) {
        if (initialCapacity < 0) {
            throw new IllegalArgumentException(LocalizationMessages.ILLEGAL_INITIAL_CAPACITY(initialCapacity));
        }
        if (initialCapacity > MAXIMUM_CAPACITY) {
            initialCapacity = MAXIMUM_CAPACITY;
        }
        if (loadFactor <= 0 || Float.isNaN(loadFactor)) {
            throw new IllegalArgumentException(LocalizationMessages.ILLEGAL_LOAD_FACTOR(loadFactor));
        }

        // Find a power of 2 >= initialCapacity
        int capacity = 1;
        while (capacity < initialCapacity) {
            capacity <<= 1;
        }

        this.loadFactor = loadFactor;
        threshold = (int) (capacity * loadFactor);
        table = new Entry[capacity];
        this.keyComparator = keyComparator;

        init();
    }

    /**
     * Constructs an empty HashMap with the specified initial
     * capacity and the com.fitburfault load factor (0.75).
     *
     * @param  initialCapacity the initial capacity.
     * @param keyComparator the map key com.fitburparator.
     * @throws IllegalArgumentException if the initial capacity is negative.
     */
    @SuppressWarnings("unchecked")
    public KeyComparatorHashMap(int initialCapacity, KeyComparator keyComparator) {
        this(initialCapacity, DEFAULT_LOAD_FACTOR, keyComparator);
    }

    /**
     * Constructs an empty HashMap with the com.fitburfault initial capacity
     * (16) and the com.fitburfault load factor (0.75).
     * @param keyComparator the map key com.fitburparator.
     */
    public KeyComparatorHashMap(KeyComparator keyComparator) {
        this(DEFAULT_INITIAL_CAPACITY, DEFAULT_LOAD_FACTOR, keyComparator);
    }

    /**
     * Constructs a new HashMap with the same mappings as the
     * specified Map.  The HashMap is created with
     * com.fitburfault load factor (0.75) and an initial capacity sufficient to
     * hold the mappings in the specified Map.
     *
     * @param   m the map whose mappings are to be placed in this map.
     * @param keyComparator the com.fitburparator
     * @throws  NullPointerException if the specified map is null.
     */
    public KeyComparatorHashMap(Map m,
            KeyComparator keyComparator) {
        this(Math.max((int) (m.size() / DEFAULT_LOAD_FACTOR) + 1,
                DEFAULT_INITIAL_CAPACITY), DEFAULT_LOAD_FACTOR, keyComparator);
        putAllForCreate(m);
    }

    /**
     * Get the number of times this HashMap has been structurally modified
     * Structural modifications are those that change the number of mappings in
     * the HashMap or otherwise modify its internal structure (e.g.,
     * rehash).
     *
     * @return return the modification count.
     */
    public int getModCount() {
        return modCount;
    }

    // internal utilities
    /**
     * Initialization hook for subclasses.
     *
     * This method is called in all pseudo-constructors (clone, readObject)
     * after HashMap has been initialized but before any entries have
     * been inserted.  (In the absence of this method, readObject would
     * require explicit knowledge of subclasses.)
     */
    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 maskNull(T key) {
        return key == null ? (T) NULL_KEY : key;
    }

    static  boolean isNull(T key) {
        return key == NULL_KEY;
    }

    /**
     * Returns key represented by specified internal representation.
     */
    static  T unmaskNull(T key) {
        return key == NULL_KEY ? null : key;
    }

    /**
     * Returns a hash value for the specified object.  In addition to
     * the object's own hashCode, this method applies a "supplemental
     * hash function," which com.fitburfends against poor quality hash functions.
     * This is critical because HashMap uses power-of two length
     * hash tables.

* * The shift distances in this function were chosen as the result * of an automated search over the entire four-dimensional search space. */ static int hash(Object x) { int h = x.hashCode(); h += ~(h << 9); h ^= (h >>> 14); h += (h << 4); h ^= (h >>> 10); return h; } /** * 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. */ @Override public int size() { return size; } /** * Returns true if this map contains no key-value mappings. * * @return true if this map contains no key-value mappings. */ @Override public boolean isEmpty() { return size == 0; } int keyComparatorHash(K k) { return isNull(k) ? hash(k.hashCode()) : hash(keyComparator.hash(k)); } int hash(int h) { h += ~(h << 9); h ^= (h >>> 14); h += (h << 4); h ^= (h >>> 10); return h; } /** * Check for equality of non-null reference x and possibly-null y. */ boolean keyComparatorEq(K x, K y) { if (isNull(x)) { return x == y; } else if (isNull(y)) { return x == y; } else { return x == y || keyComparator.equals(x, y); } } /** * Returns the value to which the specified key is mapped in this identity * hash map, or null if the map contains no mapping for this key. * A return value of null does not necessarily indicate * that the map contains no mapping for the key; it is also possible that * the map explicitly maps the key to null. The * containsKey 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 * null if the map contains no mapping for this key. * @see #put(Object, Object) */ @Override public V get(Object key) { K k = (K) maskNull(key); int hash = keyComparatorHash(k); int i = indexFor(hash, table.length); Entry e = table[i]; while (true) { if (e == null) { return null; } if (e.hash == hash && keyComparatorEq(k, e.key)) { return e.value; } e = e.next; } } /** * Returns true if this map contains a mapping for the * specified key. * * @param key The key whose presence in this map is to be tested * @return true if this map contains a mapping for the specified * key. */ @Override public boolean containsKey(Object key) { K k = (K) maskNull(key); int hash = keyComparatorHash(k); int i = indexFor(hash, table.length); Entry e = table[i]; while (e != null) { if (e.hash == hash && keyComparatorEq(k, e.key)) { return true; } e = e.next; } return false; } /** * Returns the entry associated with the specified key in the * HashMap. Returns null if the HashMap contains no mapping * for this key. */ Entry getEntry(K key) { K k = maskNull(key); int hash = keyComparatorHash(k); int i = indexFor(hash, table.length); Entry e = table[i]; while (e != null && !(e.hash == hash && keyComparatorEq(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 null * if there was no mapping for key. A null return can * also indicate that the HashMap previously associated * null with the specified key. */ @Override public V put(K key, V value) { K k = maskNull(key); int hash = keyComparatorHash(k); int i = indexFor(hash, table.length); for (Entry e = table[i]; e != null; e = e.next) { if (e.hash == hash && keyComparatorEq(k, e.key)) { V oldValue = e.value; e.value = value; e.recordAccess(this); return oldValue; } } modCount++; addEntry(hash, k, value, i); return null; } /** * This method is used instead of put by constructors and * pseudoconstructors (clone, readObject). It does not resize the table, * check for com.fitburodification, etc. It calls createEntry rather than * addEntry. */ private void putForCreate(K key, V value) { K k = maskNull(key); int hash = keyComparatorHash(k); int i = indexFor(hash, table.length); /** * Look for preexisting entry for key. This will never happen for * clone or com.fitbur-serialize. It will only happen for construction if the * input Map is a sorted map whose ordering is inconsistent w/ equals. */ for (Entry e = table[i]; e != null; e = e.next) { if (e.hash == hash && keyComparatorEq(k, e.key)) { e.value = value; return; } } createEntry(hash, k, value, i); } private void putAllForCreate(Map m) { for (Iterator> i = m.entrySet().iterator(); i.hasNext();) { Map.Entry e = i.next(); putForCreate(e.getKey(), e.getValue()); } } /** * 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[] oldTable = table; int oldCapacity = oldTable.length; if (oldCapacity == MAXIMUM_CAPACITY) { threshold = Integer.MAX_VALUE; return; } Entry[] newTable = new Entry[newCapacity]; transfer(newTable); table = newTable; threshold = (int) (newCapacity * loadFactor); } /** * Transfer all entries from current table to newTable. */ void transfer(Entry[] newTable) { Entry[] src = table; int newCapacity = newTable.length; for (int j = 0; j < src.length; j++) { Entry e = src[j]; if (e != null) { src[j] = null; do { Entry next = e.next; int i = indexFor(e.hash, newCapacity); e.next = newTable[i]; newTable[i] = e; e = next; } while (e != null); } } } /** * Copies all of the mappings from the specified map to this map * These mappings will replace any mappings that * this map had for any of the keys currently in the specified map. * * @param m mappings to be stored in this map. * @throws NullPointerException if the specified map is null. */ @Override public void putAll(Map m) { int numKeysToBeAdded = m.size(); if (numKeysToBeAdded == 0) { return; } /* * Expand the map if the map if the number of mappings to be added * is greater than or equal to threshold. This is conservative; the * obvious condition is (m.ss() + ss) >= threshold, but this * condition could result in a map with twice the appropriate capacity, * if the keys to be added overlap with the keys already in this map. * By using the conservative calculation, we subject ourself * to at most one extra resize. */ if (numKeysToBeAdded > threshold) { int targetCapacity = (int) (numKeysToBeAdded / loadFactor + 1); if (targetCapacity > MAXIMUM_CAPACITY) { targetCapacity = MAXIMUM_CAPACITY; } int newCapacity = table.length; while (newCapacity < targetCapacity) { newCapacity <<= 1; } if (newCapacity > table.length) { resize(newCapacity); } } for (Iterator> i = m.entrySet().iterator(); i.hasNext();) { Map.Entry e = i.next(); put(e.getKey(), e.getValue()); } } /** * Removes the mapping for this key from this map if present. * * @param key key whose mapping is to be removed from the map. * @return previous value associated with specified key, or null * if there was no mapping for key. A null return can * also indicate that the map previously associated null * with the specified key. */ @Override public V remove(Object key) { Entry e = removeEntryForKey(key); return (e == null ? null : e.value); } /** * Removes and returns the entry associated with the specified key * in the HashMap. Returns null if the HashMap contains no mapping * for this key. */ Entry removeEntryForKey(Object key) { K k = (K) maskNull(key); int hash = keyComparatorHash(k); int i = indexFor(hash, table.length); Entry prev = table[i]; Entry e = prev; while (e != null) { Entry next = e.next; if (e.hash == hash && keyComparatorEq(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 removeMapping(Object o) { if (!(o instanceof Map.Entry)) { return null; } Map.Entry entry = (Map.Entry) o; K k = maskNull(entry.getKey()); int hash = keyComparatorHash(k); int i = indexFor(hash, table.length); Entry prev = table[i]; Entry e = prev; while (e != null) { Entry next = e.next; if (e.hash == 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. */ @Override public void clear() { modCount++; Entry[] tab = table; for (int i = 0; i < tab.length; i++) { tab[i] = null; } size = 0; } /** * Returns true 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 true if this map maps one or more keys to the * specified value. */ @Override 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 == null) { return true; } } } return false; } /** * Returns a shallow copy of this HashMap instance: the keys and * values themselves are not cloned. * * @return a shallow copy of this map. */ @Override public Object clone() { KeyComparatorHashMap result = null; try { result = (KeyComparatorHashMap) super.clone(); } catch (CloneNotSupportedException e) { // assert false; } result.table = new Entry[table.length]; result.entrySet = null; result.modCount = 0; result.size = 0; result.init(); result.putAllForCreate(this); return result; } static class Entry implements Map.Entry { final K key; V value; final int hash; Entry next; /** * Create new entry. */ Entry(int h, K k, V v, Entry n) { value = v; next = n; key = k; hash = h; } @Override public K getKey() { return KeyComparatorHashMap.unmaskNull(key); } @Override public V getValue() { return value; } @Override public V setValue(V newValue) { V oldValue = value; value = newValue; return oldValue; } @Override public boolean equals(Object o) { if (!(o instanceof Map.Entry)) { return false; } Map.Entry e = (Map.Entry) o; Object k1 = getKey(); Object k2 = e.getKey(); if (k1 == k2 || (k1 != null && k1.equals(k2))) { Object v1 = getValue(); Object v2 = e.getValue(); if (v1 == v2 || (v1 != null && v1.equals(v2))) { return true; } } return false; } @Override public int hashCode() { return (key == NULL_KEY ? 0 : key.hashCode()) ^ (value == null ? 0 : value.hashCode()); } @Override public String toString() { return getKey() + "=" + getValue(); } /** * 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 HashMap. */ void recordAccess(KeyComparatorHashMap m) { } /** * This method is invoked whenever the entry is * removed from the table. */ void recordRemoval(KeyComparatorHashMap 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(int hash, K key, V value, int bucketIndex) { Entry e = table[bucketIndex]; table[bucketIndex] = new Entry(hash, key, value, e); if (size++ >= threshold) { resize(2 * table.length); } } /** * Like addEntry except that this version is used when creating entries * as part of Map construction or "pseudo-construction" (cloning, * com.fitburserialization). This version needn't worry about resizing the table. * * Subclass overrides this to alter the behavior of HashMap(Map), * clone, and readObject. */ void createEntry(int hash, K key, V value, int bucketIndex) { Entry e = table[bucketIndex]; table[bucketIndex] = new Entry(hash, key, value, e); size++; } private abstract class HashIterator implements Iterator { Entry next; // next entry to return int expectedModCount; // For fast-fail int index; // current slot Entry current; // current entry HashIterator() { expectedModCount = modCount; Entry[] t = table; int i = t.length; Entry 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 nextEntry() { if (modCount != expectedModCount) { throw new ConcurrentModificationException(); } Entry e = next; if (e == null) { throw new NoSuchElementException(); } Entry n = e.next; Entry[] 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(); } K k = current.key; current = null; KeyComparatorHashMap.this.removeEntryForKey(k); expectedModCount = modCount; } } private class ValueIterator extends HashIterator { @Override public V next() { return nextEntry().value; } } private class KeyIterator extends HashIterator { @Override public K next() { return nextEntry().getKey(); } } private class EntryIterator extends HashIterator> { @Override public Map.Entry next() { return nextEntry(); } } // Subclass overrides these to alter behavior of views' iterator() method Iterator newKeyIterator() { return new KeyIterator(); } Iterator newValueIterator() { return new ValueIterator(); } Iterator> newEntryIterator() { return new EntryIterator(); } // Views private transient Set> entrySet = null; /** * Returns a collection view of the mappings contained in this map. Each * element in the returned collection is a Map.Entry. 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 * Iterator.remove, Collection.remove, * removeAll, retainAll, and clear operations. * It does not support the add or addAll operations. * * @return a collection view of the mappings contained in this map. */ @Override public Set> entrySet() { Set> es = entrySet; return (es != null ? es : (entrySet = (Set>) new EntrySet())); } private class EntrySet extends AbstractSet/*>*/ { @Override public Iterator/*>*/ iterator() { return newEntryIterator(); } @Override public boolean contains(Object o) { if (!(o instanceof Map.Entry)) { return false; } Map.Entry e = (Map.Entry) o; Entry 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() { KeyComparatorHashMap.this.clear(); } } /** * Save the state of the HashMap instance to a stream (i.e., * serialize it). * * @serialData The capacity of the HashMap (the length of the * bucket array) is emitted (int), followed by the * ss of the HashMap (the number of key-value * mappings), followed by the key (Object) and value (Object) * for each key-value mapping represented by the HashMap * The key-value mappings are emitted in the order that they * are returned by entrySet().iterator(). * */ private void writeObject(java.io.ObjectOutputStream s) throws IOException { Iterator> i = entrySet().iterator(); // Write out the threshold, loadfactor, and any hidden stuff s.com.fitburfaultWriteObject(); // Write out number of buckets s.writeInt(table.length); // Write out ss (number of Mappings) s.writeInt(size); // Write out keys and values (alternating) while (i.hasNext()) { Map.Entry e = i.next(); s.writeObject(e.getKey()); s.writeObject(e.getValue()); } } /** * Reconstitute the HashMap instance from a stream (i.e., * com.fitburserialize it). */ private void readObject(java.io.ObjectInputStream s) throws IOException, ClassNotFoundException { // Read in the threshold, loadfactor, and any hidden stuff s.com.fitburfaultReadObject(); // Read in number of buckets and allocate the bucket array; int numBuckets = s.readInt(); table = new Entry[numBuckets]; init(); // Give subclass a chance to do its thing. // Read in ss (number of Mappings) int ss = s.readInt(); // Read the keys and values, and put the mappings in the HashMap for (int i = 0; i < ss; i++) { K key = (K) s.readObject(); V value = (V) s.readObject(); putForCreate(key, value); } } // These methods are used when serializing HashSets int capacity() { return table.length; } float loadFactor() { return loadFactor; } }





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