/////////////////////////////////////////////////////////////////////////////// // Copyright (c) 2001, Eric D. Friedman All Rights Reserved. // Copyright (c) 2009, Rob Eden All Rights Reserved. // Copyright (c) 2009, Jeff Randall All Rights Reserved. // // This library is free software; you can redistribute it and/or // modify it under the terms of the GNU Lesser General Public // License as published by the Free Software Foundation; either // version 2.1 of the License, or (at your option) any later version. // // This library is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License for more details. // // You should have received a copy of the GNU Lesser General Public // License along with this program; if not, write to the Free Software // Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. /////////////////////////////////////////////////////////////////////////////// package gnu.trove.map.hash; import gnu.trove.function.TObjectFunction; import gnu.trove.impl.HashFunctions; import gnu.trove.impl.hash.TObjectHash; import gnu.trove.iterator.hash.TObjectHashIterator; import gnu.trove.map.TMap; import gnu.trove.procedure.TObjectObjectProcedure; import gnu.trove.procedure.TObjectProcedure; import java.io.Externalizable; import java.io.IOException; import java.io.ObjectInput; import java.io.ObjectOutput; import java.util.*; /** * An implementation of the Map interface which uses an open addressed * hash table to store its contents. * <p/> * Created: Sun Nov 4 08:52:45 2001 * * @author Eric D. Friedman * @author Rob Eden * @author Jeff Randall * @version $Id: THashMap.java,v 1.1.2.8 2010/03/02 04:09:50 robeden Exp $ */ public class THashMap<K, V> extends TObjectHash<K> implements TMap<K, V>, Externalizable { static final long serialVersionUID = 1L; /** * the values of the map */ protected transient V[] _values; /** * Creates a new <code>THashMap</code> instance with the default * capacity and load factor. */ public THashMap() { super(); } /** * Creates a new <code>THashMap</code> instance with a prime * capacity equal to or greater than <tt>initialCapacity</tt> and * with the default load factor. * * @param initialCapacity an <code>int</code> value */ public THashMap(int initialCapacity) { super(initialCapacity); } /** * Creates a new <code>THashMap</code> instance with a prime * capacity equal to or greater than <tt>initialCapacity</tt> and * with the specified load factor. * * @param initialCapacity an <code>int</code> value * @param loadFactor a <code>float</code> value */ public THashMap(int initialCapacity, float loadFactor) { super(initialCapacity, loadFactor); } /** * Creates a new <code>THashMap</code> instance which contains the * key/value pairs in <tt>map</tt>. * * @param map a <code>Map</code> value */ public THashMap(Map<? extends K, ? extends V> map) { this(map.size()); putAll(map); } /** * Creates a new <code>THashMap</code> instance which contains the * key/value pairs in <tt>map</tt>. * * @param map a <code>Map</code> value */ public THashMap(THashMap<? extends K, ? extends V> map) { this(map.size()); putAll(map); } /** * initialize the value array of the map. * * @param initialCapacity an <code>int</code> value * @return an <code>int</code> value */ public int setUp(int initialCapacity) { int capacity; capacity = super.setUp(initialCapacity); //noinspection unchecked _values = (V[]) new Object[capacity]; return capacity; } /** * Inserts a key/value pair into the map. * * @param key an <code>Object</code> value * @param value an <code>Object</code> value * @return the previous value associated with <tt>key</tt>, * or {@code null} if none was found. */ public V put(K key, V value) { // insertKey() inserts the key if a slot if found and returns the index int index = insertKey(key); return doPut(value, index); } /** * Inserts a key/value pair into the map if the specified key is not already * associated with a value. * * @param key an <code>Object</code> value * @param value an <code>Object</code> value * @return the previous value associated with <tt>key</tt>, * or {@code null} if none was found. */ public V putIfAbsent(K key, V value) { // insertKey() inserts the key if a slot if found and returns the index int index = insertKey(key); if (index < 0) { return _values[-index - 1]; } return doPut(value, index); } private V doPut(V value, int index) { V previous = null; boolean isNewMapping = true; if (index < 0) { index = -index - 1; previous = _values[index]; isNewMapping = false; } _values[index] = value; if (isNewMapping) { postInsertHook(consumeFreeSlot); } return previous; } /** * Compares this map with another map for equality of their stored * entries. * * @param other an <code>Object</code> value * @return a <code>boolean</code> value */ @SuppressWarnings({"unchecked", "SimplifiableIfStatement"}) public boolean equals(Object other) { if (!(other instanceof Map)) { return false; } Map<K, V> that = (Map<K, V>) other; if (that.size() != this.size()) { return false; } return forEachEntry(new EqProcedure<K, V>(that)); } public int hashCode() { HashProcedure p = new HashProcedure(); forEachEntry(p); return p.getHashCode(); } public String toString() { final StringBuilder buf = new StringBuilder("{"); forEachEntry(new TObjectObjectProcedure<K, V>() { private boolean first = true; public boolean execute(K key, V value) { if (first) { first = false; } else { buf.append(", "); } buf.append(key); buf.append("="); buf.append(value); return true; } }); buf.append("}"); return buf.toString(); } private final class HashProcedure implements TObjectObjectProcedure<K, V> { private int h = 0; public int getHashCode() { return h; } public final boolean execute(K key, V value) { h += HashFunctions.hash(key) ^ (value == null ? 0 : value.hashCode()); return true; } } private final class EqProcedure<K, V> implements TObjectObjectProcedure<K, V> { private final Map<K, V> _otherMap; EqProcedure(Map<K, V> otherMap) { _otherMap = otherMap; } public final boolean execute(K key, V value) { // Check to make sure the key is there. This avoids problems that come up with // null values. Since it is only caused in that cause, only do this when the // value is null (to avoid extra work). if (value == null && !_otherMap.containsKey(key)) { return false; } V oValue = _otherMap.get(key); return oValue == value || (oValue != null && THashMap.this.equals(oValue, value)); } } /** * Executes <tt>procedure</tt> for each key in the map. * * @param procedure a <code>TObjectProcedure</code> value * @return false if the loop over the keys terminated because * the procedure returned false for some key. */ public boolean forEachKey(TObjectProcedure<? super K> procedure) { return forEach(procedure); } /** * Executes <tt>procedure</tt> for each value in the map. * * @param procedure a <code>TObjectProcedure</code> value * @return false if the loop over the values terminated because * the procedure returned false for some value. */ public boolean forEachValue(TObjectProcedure<? super V> procedure) { V[] values = _values; Object[] set = _set; for (int i = values.length; i-- > 0;) { if (set[i] != FREE && set[i] != REMOVED && !procedure.execute(values[i])) { return false; } } return true; } /** * Executes <tt>procedure</tt> for each key/value entry in the * map. * * @param procedure a <code>TObjectObjectProcedure</code> value * @return false if the loop over the entries terminated because * the procedure returned false for some entry. */ @SuppressWarnings({"unchecked"}) public boolean forEachEntry(TObjectObjectProcedure<? super K, ? super V> procedure) { Object[] keys = _set; V[] values = _values; for (int i = keys.length; i-- > 0;) { if (keys[i] != FREE && keys[i] != REMOVED && !procedure.execute((K) keys[i], values[i])) { return false; } } return true; } /** * Retains only those entries in the map for which the procedure * returns a true value. * * @param procedure determines which entries to keep * @return true if the map was modified. */ @SuppressWarnings({"unchecked"}) public boolean retainEntries(TObjectObjectProcedure<? super K, ? super V> procedure) { boolean modified = false; Object[] keys = _set; V[] values = _values; // Temporarily disable compaction. This is a fix for bug #1738760 tempDisableAutoCompaction(); try { for (int i = keys.length; i-- > 0;) { if (keys[i] != FREE && keys[i] != REMOVED && !procedure.execute((K) keys[i], values[i])) { removeAt(i); modified = true; } } } finally { reenableAutoCompaction(true); } return modified; } /** * Transform the values in this map using <tt>function</tt>. * * @param function a <code>TObjectFunction</code> value */ public void transformValues(TObjectFunction<V, V> function) { V[] values = _values; Object[] set = _set; for (int i = values.length; i-- > 0;) { if (set[i] != FREE && set[i] != REMOVED) { values[i] = function.execute(values[i]); } } } /** * rehashes the map to the new capacity. * * @param newCapacity an <code>int</code> value */ @SuppressWarnings({"unchecked"}) protected void rehash(int newCapacity) { int oldCapacity = _set.length; int oldSize = size(); Object oldKeys[] = _set; V oldVals[] = _values; _set = new Object[newCapacity]; Arrays.fill(_set, FREE); _values = (V[]) new Object[newCapacity]; // Process entries from the old array, skipping free and removed slots. Put the // values into the appropriate place in the new array. int count = 0; for (int i = oldCapacity; i-- > 0;) { Object o = oldKeys[i]; if (o == FREE || o == REMOVED) continue; int index = insertKey((K) o); if (index < 0) { throwObjectContractViolation(_set[(-index - 1)], o, size(), oldSize, oldKeys); } _values[index] = oldVals[i]; // count++; } // Last check: size before and after should be the same reportPotentialConcurrentMod(size(), oldSize); } /** * retrieves the value for <tt>key</tt> * * @param key an <code>Object</code> value * @return the value of <tt>key</tt> or null if no such mapping exists. */ @SuppressWarnings({"unchecked"}) public V get(Object key) { int index = index(key); return index < 0 ? null : _values[index]; } /** * Empties the map. */ public void clear() { if (size() == 0) { return; // optimization } super.clear(); Arrays.fill(_set, 0, _set.length, FREE); Arrays.fill(_values, 0, _values.length, null); } /** * Deletes a key/value pair from the map. * * @param key an <code>Object</code> value * @return an <code>Object</code> value */ @SuppressWarnings({"unchecked"}) public V remove(Object key) { V prev = null; int index = index(key); if (index >= 0) { prev = _values[index]; removeAt(index); // clear key,state; adjust size } return prev; } /** * removes the mapping at <tt>index</tt> from the map. * * @param index an <code>int</code> value */ public void removeAt(int index) { _values[index] = null; super.removeAt(index); // clear key, state; adjust size } /** * Returns a view on the values of the map. * * @return a <code>Collection</code> value */ public Collection<V> values() { return new ValueView(); } /** * returns a Set view on the keys of the map. * * @return a <code>Set</code> value */ public Set<K> keySet() { return new KeyView(); } /** * Returns a Set view on the entries of the map. * * @return a <code>Set</code> value */ public Set<Map.Entry<K, V>> entrySet() { return new EntryView(); } /** * checks for the presence of <tt>val</tt> in the values of the map. * * @param val an <code>Object</code> value * @return a <code>boolean</code> value */ public boolean containsValue(Object val) { Object[] set = _set; V[] vals = _values; // special case null values so that we don't have to // perform null checks before every call to equals() if (null == val) { for (int i = vals.length; i-- > 0;) { if ((set[i] != FREE && set[i] != REMOVED) && val == vals[i]) { return true; } } } else { for (int i = vals.length; i-- > 0;) { if ((set[i] != FREE && set[i] != REMOVED) && (val == vals[i] || equals(val, vals[i]))) { return true; } } } // end of else return false; } /** * checks for the present of <tt>key</tt> in the keys of the map. * * @param key an <code>Object</code> value * @return a <code>boolean</code> value */ public boolean containsKey(Object key) { //noinspection unchecked return contains(key); } /** * copies the key/value mappings in <tt>map</tt> into this map. * * @param map a <code>Map</code> value */ public void putAll(Map<? extends K, ? extends V> map) { ensureCapacity(map.size()); // could optimize this for cases when map instanceof THashMap for (Map.Entry<? extends K, ? extends V> e : map.entrySet()) { put(e.getKey(), e.getValue()); } } /** * a view onto the values of the map. */ protected class ValueView extends MapBackedView<V> { @SuppressWarnings({"unchecked"}) public Iterator<V> iterator() { return new TObjectHashIterator(THashMap.this) { protected V objectAtIndex(int index) { return _values[index]; } }; } public boolean containsElement(V value) { return containsValue(value); } public boolean removeElement(V value) { Object[] values = _values; Object[] set = _set; for (int i = values.length; i-- > 0;) { if ((set[i] != FREE && set[i] != REMOVED) && value == values[i] || (null != values[i] && THashMap.this.equals(values[i], value))) { removeAt(i); return true; } } return false; } } /** * a view onto the entries of the map. */ protected class EntryView extends MapBackedView<Map.Entry<K, V>> { private final class EntryIterator extends TObjectHashIterator { EntryIterator(THashMap<K, V> map) { super(map); } @SuppressWarnings({"unchecked"}) public Entry objectAtIndex(final int index) { return new Entry((K) _set[index], _values[index], index); } } @SuppressWarnings({"unchecked"}) public Iterator<Map.Entry<K, V>> iterator() { return new EntryIterator(THashMap.this); } public boolean removeElement(Map.Entry<K, V> entry) { if (entry == null) return false; // have to effectively reimplement Map.remove here // because we need to return true/false depending on // whether the removal took place. Since the Entry's // value can be null, this means that we can't rely // on the value of the object returned by Map.remove() // to determine whether a deletion actually happened. // // Note also that the deletion is only legal if // both the key and the value match. V val; int index; K key = keyForEntry(entry); index = index(key); if (index >= 0) { val = valueForEntry(entry); if (val == _values[index] || (null != val && THashMap.this.equals(val, _values[index]))) { removeAt(index); // clear key,state; adjust size return true; } } return false; } public boolean containsElement(Map.Entry<K, V> entry) { V val = get(keyForEntry(entry)); V entryValue = entry.getValue(); return entryValue == val || (null != val && THashMap.this.equals(val, entryValue)); } protected V valueForEntry(Map.Entry<K, V> entry) { return entry.getValue(); } protected K keyForEntry(Map.Entry<K, V> entry) { return entry.getKey(); } } private abstract class MapBackedView<E> extends AbstractSet<E> implements Set<E>, Iterable<E> { public abstract Iterator<E> iterator(); public abstract boolean removeElement(E key); public abstract boolean containsElement(E key); @SuppressWarnings({"unchecked"}) public boolean contains(Object key) { return containsElement((E) key); } @SuppressWarnings({"unchecked"}) public boolean remove(Object o) { try { return removeElement((E) o); } catch (ClassCastException ex) { return false; } } // public boolean containsAll( Collection<?> collection ) { // for ( Object element : collection ) { // if ( !contains( element ) ) { // return false; // } // } // return true; // } public void clear() { THashMap.this.clear(); } public boolean add(E obj) { throw new UnsupportedOperationException(); } public int size() { return THashMap.this.size(); } public Object[] toArray() { Object[] result = new Object[size()]; Iterator<E> e = iterator(); for (int i = 0; e.hasNext(); i++) { result[i] = e.next(); } return result; } @SuppressWarnings({"unchecked"}) public <T> T[] toArray(T[] a) { int size = size(); if (a.length < size) { a = (T[]) java.lang.reflect.Array.newInstance(a.getClass().getComponentType(), size); } Iterator<E> it = iterator(); Object[] result = a; for (int i = 0; i < size; i++) { result[i] = it.next(); } if (a.length > size) { a[size] = null; } return a; } public boolean isEmpty() { return THashMap.this.isEmpty(); } public boolean addAll(Collection<? extends E> collection) { throw new UnsupportedOperationException(); } @SuppressWarnings({"SuspiciousMethodCalls"}) public boolean retainAll(Collection<?> collection) { boolean changed = false; Iterator<E> i = iterator(); while (i.hasNext()) { if (!collection.contains(i.next())) { i.remove(); changed = true; } } return changed; } public String toString() { Iterator<E> i = iterator(); if (!i.hasNext()) return "{}"; StringBuilder sb = new StringBuilder(); sb.append('{'); for (; ;) { E e = i.next(); sb.append(e == this ? "(this Collection)" : e); if (!i.hasNext()) return sb.append('}').toString(); sb.append(", "); } } } /** * a view onto the keys of the map. */ protected class KeyView extends MapBackedView<K> { @SuppressWarnings({"unchecked"}) public Iterator<K> iterator() { return new TObjectHashIterator<K>(THashMap.this); } public boolean removeElement(K key) { return null != THashMap.this.remove(key); } public boolean containsElement(K key) { return THashMap.this.contains(key); } } final class Entry implements Map.Entry<K, V> { private K key; private V val; private final int index; Entry(final K key, V value, final int index) { this.key = key; this.val = value; this.index = index; } public K getKey() { return key; } public V getValue() { return val; } public V setValue(V o) { if (_values[index] != val) { throw new ConcurrentModificationException(); } // need to return previous value V retval = val; // update this entry's value, in case setValue is called again _values[index] = o; val = o; return retval; } public boolean equals(Object o) { if (o instanceof Map.Entry) { Map.Entry<K, V> e1 = this; Map.Entry e2 = (Map.Entry) o; return (THashMap.this.equals(e1.getKey(), e2.getKey())) && (THashMap.this.equals(e1.getValue(), e1.getValue())); } return false; } public int hashCode() { return (getKey() == null ? 0 : getKey().hashCode()) ^ (getValue() == null ? 0 : getValue().hashCode()); } @Override public String toString() { return key + "=" + val; } } public void writeExternal(ObjectOutput out) throws IOException { // VERSION out.writeByte(1); // NOTE: Super was not written in version 0 super.writeExternal(out); // NUMBER OF ENTRIES out.writeInt(_size); // ENTRIES for (int i = _set.length; i-- > 0;) { if (_set[i] != REMOVED && _set[i] != FREE) { out.writeObject(_set[i]); out.writeObject(_values[i]); } } } public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException { // VERSION byte version = in.readByte(); // NOTE: super was not written in version 0 if (version != 0) { super.readExternal(in); } // NUMBER OF ENTRIES int size = in.readInt(); setUp(size); // ENTRIES while (size-- > 0) { //noinspection unchecked K key = (K) in.readObject(); //noinspection unchecked V val = (V) in.readObject(); put(key, val); } } } // THashMap