content: package org.apache.solr.request.mdrill;
  
  import java.io.IOException;
  import java.io.Serializable;
  import java.util.AbstractCollection;
  import java.util.AbstractSet;
  import java.util.Collection;
  import java.util.ConcurrentModificationException;
  import java.util.Iterator;
  import java.util.Map;
  import java.util.NoSuchElementException;
  import java.util.Set;
  
  
  public class QuickHashMap<K,V>
  extends QuickHashMapBase<K,V>
  implements Map<K,V>, Cloneable, Serializable
  {
  
  static final int DEFAULT_INITIAL_CAPACITY = 16;
  
  
  static final int MAXIMUM_CAPACITY = 1 << 30;
  
  static final float DEFAULT_LOAD_FACTOR = 0.75f;
  
  transient Entry[] table;
  
  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 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;
  
  /**
   * Constructs an empty <tt>HashMap</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 QuickHashMap(int initialCapacity, float loadFactor) {
      if (initialCapacity < 0)
          throw new IllegalArgumentException("Illegal initial capacity: " +
                                             initialCapacity);
      if (initialCapacity > MAXIMUM_CAPACITY)
          initialCapacity = MAXIMUM_CAPACITY;
      if (loadFactor <= 0 || Float.isNaN(loadFactor))
          throw new IllegalArgumentException("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];
      init();
  }
  
  /**
   * Constructs an empty <tt>HashMap</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 QuickHashMap(int initialCapacity) {
      this(initialCapacity, DEFAULT_LOAD_FACTOR);
  }
  
  /**
   * Constructs an empty <tt>HashMap</tt> with the default initial capacity
   * (16) and the default load factor (0.75).
   */
  public QuickHashMap() {
      this.loadFactor = DEFAULT_LOAD_FACTOR;
      threshold = (int)(DEFAULT_INITIAL_CAPACITY * DEFAULT_LOAD_FACTOR);
      table = new Entry[DEFAULT_INITIAL_CAPACITY];
      init();
  }
  
  /**
   * Constructs a new <tt>HashMap</tt> with the same mappings as the
   * specified <tt>Map</tt>.  The <tt>HashMap</tt> is created with
   * default load factor (0.75) and an initial capacity sufficient to
   * hold the mappings in the specified <tt>Map</tt>.
   *
   * @param   m the map whose mappings are to be placed in this map
   * @throws  NullPointerException if the specified map is null
   */
  public QuickHashMap(Map<? extends K, ? extends V> m) {
      this(Math.max((int) (m.size() / DEFAULT_LOAD_FACTOR) + 1,
                    DEFAULT_INITIAL_CAPACITY), DEFAULT_LOAD_FACTOR);
      putAllForCreate(m);
  }
  
  // internal utilities
  
  /**
   * Initialization hook for subclasses. This method is called
   * in all constructors and 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() {
  }
  
  /**
   * Applies a supplemental hash function to a given hashCode, which
   * defends against poor quality hash functions.  This is critical
   * because HashMap uses power-of-two length hash tables, that
   * otherwise encounter collisions for hashCodes that do not differ
   * in lower bits. Note: Null keys always map to hash 0, thus index 0.
   */
  static int hash(int h) {
      // This function ensures that hashCodes that differ only by
      // constant multiples at each bit position have a bounded
      // number of collisions (approximately 8 at default load factor).
      h ^= (h >>> 20) ^ (h >>> 12);
      return h ^ (h >>> 7) ^ (h >>> 4);
  }
  
  /**
   * 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,
   * or {@code null} if this map contains no mapping for the key.
   *
   * <p>More formally, if this map contains a mapping from a key
   * {@code k} to a value {@code v} such that {@code (key==null ? k==null :
   * key.equals(k))}, then this method returns {@code v}; otherwise
   * it returns {@code null}.  (There can be at most one such mapping.)
   *
   * <p>A return value of {@code null} does not <i>necessarily</i>
   * indicate that the map contains no mapping for the key; it's also
   * possible that the map explicitly maps the key to {@code null}.
   * The {@link #containsKey containsKey} operation may be used to
   * distinguish these two cases.
   *
   * @see #put(Object, Object)
   */
  public V get(Object key) {
       int hash = hash(key.hashCode());
      for (Entry<K,V> e = table[indexFor(hash, table.length)];
           e != null;
           e = e.next) {
          Object k=e.key;
          if (e.hash == hash && key.equals(k))
              return e.value;
      }
      return null;
  }
  
  /**
   * Offloaded version of get() to look up null keys.  Null keys map
   * to index 0.  This null case is split out into separate methods
   * for the sake of performance in the two most commonly used
   * operations (get and put), but incorporated with conditionals in
   * others.
   */
  private V getForNullKey() {
      for (Entry<K,V> e = table[0]; e != null; e = e.next) {
          if (e.key == null)
              return e.value;
      }
      return null;
  }
  
  /**
   * 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) {
      return getEntry(key) != null;
  }
  
  /**
   * Returns the entry associated with the specified key in the
   * HashMap.  Returns null if the HashMap contains no mapping
   * for the key.
   */
  final Entry<K,V> getEntry(Object key) {
      int hash = (key == null) ? 0 : hash(key.hashCode());
      for (Entry<K,V> e = table[indexFor(hash, table.length)];
           e != null;
           e = e.next) {
          Object k;
          if (e.hash == hash &&
              ((k = e.key) == key || (key != null && key.equals(k))))
              return e;
      }
      return null;
  }
  
  
  /**
   * Associates the specified value with the specified key in this map.
   * If the map previously contained a mapping for the 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 the previous value associated with <tt>key</tt>, or
   *         <tt>null</tt> if there was no mapping for <tt>key</tt>.
   *         (A <tt>null</tt> return can also indicate that the map
   *         previously associated <tt>null</tt> with <tt>key</tt>.)
   */
  public V put(K key, V value) {
      int hash = hash(key.hashCode());
      int i = indexFor(hash, table.length);
      for (Entry<K,V> e = table[i]; e != null; e = e.next) {
          Object k;
          if (e.hash == hash && ((k = e.key) == key || key.equals(k))) {
              V oldValue = e.value;
              e.value = value;
              e.recordAccess(this);
              return oldValue;
          }
      }
  
      modCount++;
      addEntry(hash, key, value, i);
      return null;
  }
  
  /**
   * Offloaded version of put for null keys
   */
  private V putForNullKey(V value) {
      for (Entry<K,V> e = table[0]; e != null; e = e.next) {
          if (e.key == null) {
              V oldValue = e.value;
              e.value = value;
              e.recordAccess(this);
              return oldValue;
          }
      }
      modCount++;
      addEntry(0, null, value, 0);
      return null;
  }
  
  /**
   * 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, V value) {
      int hash = (key == null) ? 0 : hash(key.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,V> e = table[i]; e != null; e = e.next) {
          Object k;
          if (e.hash == hash &&
              ((k = e.key) == key || (key != null && key.equals(k)))) {
              e.value = value;
              return;
          }
      }
  
      createEntry(hash, key, value, i);
  }
  
  private void putAllForCreate(Map<? extends K, ? extends V> m) {
      for (Iterator<? extends Map.Entry<? extends K, ? extends V>> i = m.entrySet().iterator(); i.hasNext(); ) {
          Map.Entry<? extends K, ? extends V> 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);
  }
  
  /**
   * Transfers 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<K,V> e = src[j];
          if (e != null) {
              src[j] = null;
              do {
                  Entry<K,V> 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
   */
  public void putAll(Map<? extends K, ? extends V> 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.size() + size) >= 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<? extends Map.Entry<? extends K, ? extends V>> i = m.entrySet().iterator(); i.hasNext(); ) {
          Map.Entry<? extends K, ? extends V> e = i.next();
          put(e.getKey(), e.getValue());
      }
  }
  
  /**
   * Removes the mapping for the specified key from this map if present.
   *
   * @param  key key whose mapping is to be removed from the map
   * @return the previous value associated with <tt>key</tt>, or
   *         <tt>null</tt> if there was no mapping for <tt>key</tt>.
   *         (A <tt>null</tt> return can also indicate that the map
   *         previously associated <tt>null</tt> with <tt>key</tt>.)
   */
  public V remove(Object key) {
      Entry<K,V> 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.
   */
  final Entry<K,V> removeEntryForKey(Object key) {
      int hash = (key == null) ? 0 : hash(key.hashCode());
      int i = indexFor(hash, table.length);
      Entry<K,V> prev = table[i];
      Entry<K,V> e = prev;
  
      while (e != null) {
          Entry<K,V> next = e.next;
          Object k;
          if (e.hash == hash &&
              ((k = e.key) == key || (key != null && key.equals(k)))) {
              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.
   */
  final Entry<K,V> removeMapping(Object o) {
      if (!(o instanceof Map.Entry))
          return null;
  
      Map.Entry<K,V> entry = (Map.Entry<K,V>) o;
      Object key = entry.getKey();
      int hash = (key == null) ? 0 : hash(key.hashCode());
      int i = indexFor(hash, table.length);
      Entry<K,V> prev = table[i];
      Entry<K,V> e = prev;
  
      while (e != null) {
          Entry<K,V> 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 of the mappings from this map.
   * The map will be empty after this call returns.
   */
  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 == null)
                  return true;
  return false;
  }
  
  /**
   * Returns a shallow copy of this <tt>HashMap</tt> instance: the keys and
   * values themselves are not cloned.
   *
   * @return a shallow copy of this map
   */
  public Object clone() {
      QuickHashMap<K,V> result = null;
  try {
      result = (QuickHashMap<K,V>)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<K,V> implements Map.Entry<K,V> {
      final K key;
      V value;
      Entry<K,V> next;
      final int hash;
  
      /**
       * Creates new entry.
       */
      Entry(int h, K k, V v, Entry<K,V> n) {
          value = v;
          next = n;
          key = k;
          hash = h;
      }
  
      public final K getKey() {
          return key;
      }
  
      public final V getValue() {
          return value;
      }
  
      public final V setValue(V newValue) {
      V oldValue = value;
          value = newValue;
          return oldValue;
      }
  
      public final 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;
      }
  
      public final int hashCode() {
          return (key==null   ? 0 : key.hashCode()) ^
                 (value==null ? 0 : value.hashCode());
      }
  
      public final 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(QuickHashMap<K,V> m) {
      }
  
      /**
       * This method is invoked whenever the entry is
       * removed from the table.
       */
      void recordRemoval(QuickHashMap<K,V> m) {
      }
  }
  
  /**
   * Adds 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<K,V> e = table[bucketIndex];
      table[bucketIndex] = new Entry<K,V>(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,
   * deserialization).  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<K,V> e = table[bucketIndex];
      table[bucketIndex] = new Entry<K,V>(hash, key, value, e);
      size++;
  }
  
  private abstract class HashIterator<E> implements Iterator<E> {
      Entry<K,V> next;	// next entry to return
      int expectedModCount;	// For fast-fail
      int index;		// current slot
      Entry<K,V> current;	// current entry
  
      HashIterator() {
          expectedModCount = modCount;
          if (size > 0) { // advance to first entry
              Entry[] t = table;
              while (index < t.length && (next = t[index++]) == null)
                  ;
          }
      }
  
      public final boolean hasNext() {
          return next != null;
      }
  
      final Entry<K,V> nextEntry() {
          if (modCount != expectedModCount)
              throw new ConcurrentModificationException();
          Entry<K,V> e = next;
          if (e == null)
              throw new NoSuchElementException();
  
          if ((next = e.next) == null) {
              Entry[] t = table;
              while (index < t.length && (next = t[index++]) == null)
                  ;
          }
      current = e;
          return e;
      }
  
      public void remove() {
          if (current == null)
              throw new IllegalStateException();
          if (modCount != expectedModCount)
              throw new ConcurrentModificationException();
          Object k = current.key;
          current = null;
          QuickHashMap.this.removeEntryForKey(k);
          expectedModCount = modCount;
      }
  
  }
  
  private final class ValueIterator extends HashIterator<V> {
      public V next() {
          return nextEntry().value;
      }
  }
  
  private final class KeyIterator extends HashIterator<K> {
      public K next() {
          return nextEntry().getKey();
      }
  }
  
  private final class EntryIterator extends HashIterator<Map.Entry<K,V>> {
      public Map.Entry<K,V> next() {
          return nextEntry();
      }
  }
  
  // Subclass overrides these to alter behavior of views' iterator() method
  Iterator<K> newKeyIterator()   {
      return new KeyIterator();
  }
  Iterator<V> newValueIterator()   {
      return new ValueIterator();
  }
  Iterator<Map.Entry<K,V>> newEntryIterator()   {
      return new EntryIterator();
  }
  
  
  // Views
  
  private transient Set<Map.Entry<K,V>> entrySet = null;
  
  /**
   * Returns a {@link 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.  If the map is modified
   * while an iteration over the set is in progress (except through
   * the iterator's own <tt>remove</tt> operation), the results of
   * the iteration are undefined.  The set supports element removal,
   * which removes the corresponding mapping from the 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.
   */
  public Set<K> keySet() {
      Set<K> ks = keySet;
      return (ks != null ? ks : (keySet = new KeySet()));
  }
  
  private final class KeySet extends AbstractSet<K> {
      public Iterator<K> iterator() {
          return newKeyIterator();
      }
      public int size() {
          return size;
      }
      public boolean contains(Object o) {
          return containsKey(o);
      }
      public boolean remove(Object o) {
          return QuickHashMap.this.removeEntryForKey(o) != null;
      }
      public void clear() {
          QuickHashMap.this.clear();
      }
  }
  
  /**
   * Returns a {@link Collection} view of the values contained in this map.
   * The collection is backed by the map, so changes to the map are
   * reflected in the collection, and vice-versa.  If the map is
   * modified while an iteration over the collection is in progress
   * (except through the iterator's own <tt>remove</tt> operation),
   * the results of the iteration are undefined.  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.
   */
  public Collection<V> values() {
      Collection<V> vs = values;
      return (vs != null ? vs : (values = new Values()));
  }
  
  private final class Values extends AbstractCollection<V> {
      public Iterator<V> iterator() {
          return newValueIterator();
      }
      public int size() {
          return size;
      }
      public boolean contains(Object o) {
          return containsValue(o);
      }
      public void clear() {
          QuickHashMap.this.clear();
      }
  }
  
  /**
   * Returns a {@link Set} view of the mappings contained in this map.
   * The set is backed by the map, so changes to the map are
   * reflected in the set, and vice-versa.  If the map is modified
   * while an iteration over the set is in progress (except through
   * the iterator's own <tt>remove</tt> operation, or through the
   * <tt>setValue</tt> operation on a map entry returned by the
   * iterator) the results of the iteration are undefined.  The set
   * supports element removal, which removes the corresponding
   * mapping from the 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 mappings contained in this map
   */
  public Set<Map.Entry<K,V>> entrySet() {
  return entrySet0();
  }
  
  private Set<Map.Entry<K,V>> entrySet0() {
      Set<Map.Entry<K,V>> es = entrySet;
      return es != null ? es : (entrySet = new EntrySet());
  }
  
  private final class EntrySet extends AbstractSet<Map.Entry<K,V>> {
      public Iterator<Map.Entry<K,V>> iterator() {
          return newEntryIterator();
      }
      public boolean contains(Object o) {
          if (!(o instanceof Map.Entry))
              return false;
          Map.Entry<K,V> e = (Map.Entry<K,V>) o;
          Entry<K,V> candidate = getEntry(e.getKey());
          return candidate != null && candidate.equals(e);
      }
      public boolean remove(Object o) {
          return removeMapping(o) != null;
      }
      public int size() {
          return size;
      }
      public void clear() {
          QuickHashMap.this.clear();
      }
  }
  
  /**
   * Save the state of the <tt>HashMap</tt> instance to a stream (i.e.,
   * serialize it).
   *
   * @serialData The <i>capacity</i> of the HashMap (the length of the
   *		   bucket array) is emitted (int), followed by the
   *		   <i>size</i> (an int, the number of key-value
   *		   mappings), followed by the key (Object) and value (Object)
   *		   for each key-value mapping.  The key-value mappings are
   *		   emitted in no particular order.
   */
  private void writeObject(java.io.ObjectOutputStream s)
      throws IOException
  {
  Iterator<Map.Entry<K,V>> i =
      (size > 0) ? entrySet0().iterator() : null;
  
  // Write out the threshold, loadfactor, and any hidden stuff
  s.defaultWriteObject();
  
  // Write out number of buckets
  s.writeInt(table.length);
  
  // Write out size (number of Mappings)
  s.writeInt(size);
  
      // Write out keys and values (alternating)
  if (i != null) {
      while (i.hasNext()) {
  	Map.Entry<K,V> e = i.next();
  	s.writeObject(e.getKey());
  	s.writeObject(e.getValue());
      }
      }
  }
  
  private static final long serialVersionUID = 362498820763181265L;
  
  /**
   * Reconstitute the <tt>HashMap</tt> instance from a stream (i.e.,
   * deserialize it).
   */
  private void readObject(java.io.ObjectInputStream s)
       throws IOException, ClassNotFoundException
  {
  // Read in the threshold, loadfactor, and any hidden stuff
  s.defaultReadObject();
  
  // 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 size (number of Mappings)
  int size = s.readInt();
  
  // Read the keys and values, and put the mappings in the HashMap
  for (int i=0; i<size; 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;   }
  }