|
What this is
This file is included in the DevDaily.com
"Java Source Code
Warehouse" project. The intent of this project is to help you "Learn
Java by Example" TM.
Other links
The source code
///////////////////////////////////////////////////////////////////////////////
// Copyright (c) 2001, Eric D. Friedman 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;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
/**
* An open addressed Map implementation for float keys and int values.
*
* Created: Sun Nov 4 08:52:45 2001
*
* @author Eric D. Friedman
* @version $Id: TFloatIntHashMap.java,v 1.15 2003/11/21 17:32:30 ericdf Exp $
*/
public class TFloatIntHashMap extends TFloatHash implements Serializable {
/** the values of the map */
protected transient int[] _values;
/**
* Creates a new TFloatIntHashMap instance with the default
* capacity and load factor.
*/
public TFloatIntHashMap() {
super();
}
/**
* Creates a new TFloatIntHashMap instance with a prime
* capacity equal to or greater than initialCapacity and
* with the default load factor.
*
* @param initialCapacity an int value
*/
public TFloatIntHashMap(int initialCapacity) {
super(initialCapacity);
}
/**
* Creates a new TFloatIntHashMap instance with a prime
* capacity equal to or greater than initialCapacity and
* with the specified load factor.
*
* @param initialCapacity an int value
* @param loadFactor a float value
*/
public TFloatIntHashMap(int initialCapacity, float loadFactor) {
super(initialCapacity, loadFactor);
}
/**
* Creates a new TFloatIntHashMap instance with the default
* capacity and load factor.
* @param strategy used to compute hash codes and to compare keys.
*/
public TFloatIntHashMap(TFloatHashingStrategy strategy) {
super(strategy);
}
/**
* Creates a new TFloatIntHashMap instance whose capacity
* is the next highest prime above initialCapacity + 1
* unless that value is already prime.
*
* @param initialCapacity an int value
* @param strategy used to compute hash codes and to compare keys.
*/
public TFloatIntHashMap(int initialCapacity, TFloatHashingStrategy strategy) {
super(initialCapacity, strategy);
}
/**
* Creates a new TFloatIntHashMap instance with a prime
* value at or near the specified capacity and load factor.
*
* @param initialCapacity used to find a prime capacity for the table.
* @param loadFactor used to calculate the threshold over which
* rehashing takes place.
* @param strategy used to compute hash codes and to compare keys.
*/
public TFloatIntHashMap(int initialCapacity, float loadFactor, TFloatHashingStrategy strategy) {
super(initialCapacity, loadFactor, strategy);
}
/**
* @return a deep clone of this collection
*/
public Object clone() {
TFloatIntHashMap m = (TFloatIntHashMap)super.clone();
m._values = (int[])this._values.clone();
return m;
}
/**
* @return a TFloatIntIterator with access to this map's keys and values
*/
public TFloatIntIterator iterator() {
return new TFloatIntIterator(this);
}
/**
* initializes the hashtable to a prime capacity which is at least
* initialCapacity + 1.
*
* @param initialCapacity an int value
* @return the actual capacity chosen
*/
protected int setUp(int initialCapacity) {
int capacity;
capacity = super.setUp(initialCapacity);
_values = new int[capacity];
return capacity;
}
/**
* Inserts a key/value pair into the map.
*
* @param key an float value
* @param value an int value
* @return the previous value associated with key,
* or (int)0 if none was found.
*/
public int put(float key, int value) {
byte previousState;
int previous = (int)0;
int index = insertionIndex(key);
boolean isNewMapping = true;
if (index < 0) {
index = -index -1;
previous = _values[index];
isNewMapping = false;
}
previousState = _states[index];
_set[index] = key;
_states[index] = FULL;
_values[index] = value;
if (isNewMapping) {
postInsertHook(previousState == FREE);
}
return previous;
}
/**
* rehashes the map to the new capacity.
*
* @param newCapacity an int value
*/
protected void rehash(int newCapacity) {
int oldCapacity = _set.length;
float oldKeys[] = _set;
int oldVals[] = _values;
byte oldStates[] = _states;
_set = new float[newCapacity];
_values = new int[newCapacity];
_states = new byte[newCapacity];
for (int i = oldCapacity; i-- > 0;) {
if(oldStates[i] == FULL) {
float o = oldKeys[i];
int index = insertionIndex(o);
_set[index] = o;
_values[index] = oldVals[i];
_states[index] = FULL;
}
}
}
/**
* retrieves the value for key
*
* @param key an float value
* @return the value of key or (int)0 if no such mapping exists.
*/
public int get(float key) {
int index = index(key);
return index < 0 ? (int)0 : _values[index];
}
/**
* Empties the map.
*
*/
public void clear() {
super.clear();
float[] keys = _set;
int[] vals = _values;
byte[] states = _states;
for (int i = keys.length; i-- > 0;) {
keys[i] = (float)0;
vals[i] = (int)0;
states[i] = FREE;
}
}
/**
* Deletes a key/value pair from the map.
*
* @param key an float value
* @return an int value, or (int)0 if no mapping for key exists
*/
public int remove(float key) {
int prev = (int)0;
int index = index(key);
if (index >= 0) {
prev = _values[index];
removeAt(index); // clear key,state; adjust size
}
return prev;
}
/**
* Compares this map with another map for equality of their stored
* entries.
*
* @param other an Object value
* @return a boolean value
*/
public boolean equals(Object other) {
if (! (other instanceof TFloatIntHashMap)) {
return false;
}
TFloatIntHashMap that = (TFloatIntHashMap)other;
if (that.size() != this.size()) {
return false;
}
return forEachEntry(new EqProcedure(that));
}
public int hashCode() {
HashProcedure p = new HashProcedure();
forEachEntry(p);
return p.getHashCode();
}
private final class HashProcedure implements TFloatIntProcedure {
private int h = 0;
public int getHashCode() {
return h;
}
public final boolean execute(float key, int value) {
h += (_hashingStrategy.computeHashCode(key) ^ HashFunctions.hash(value));
return true;
}
}
private static final class EqProcedure implements TFloatIntProcedure {
private final TFloatIntHashMap _otherMap;
EqProcedure(TFloatIntHashMap otherMap) {
_otherMap = otherMap;
}
public final boolean execute(float key, int value) {
int index = _otherMap.index(key);
if (index >= 0 && eq(value, _otherMap.get(key))) {
return true;
}
return false;
}
/**
* Compare two ints for equality.
*/
private final boolean eq(int v1, int v2) {
return v1 == v2;
}
}
/**
* removes the mapping at index from the map.
*
* @param index an int value
*/
protected void removeAt(int index) {
super.removeAt(index); // clear key, state; adjust size
_values[index] = (int)0;
}
/**
* Returns the values of the map.
*
* @return a Collection value
*/
public int[] getValues() {
int[] vals = new int[size()];
int[] v = _values;
byte[] states = _states;
for (int i = v.length, j = 0; i-- > 0;) {
if (states[i] == FULL) {
vals[j++] = v[i];
}
}
return vals;
}
/**
* returns the keys of the map.
*
* @return a Set value
*/
public float[] keys() {
float[] keys = new float[size()];
float[] k = _set;
byte[] states = _states;
for (int i = k.length, j = 0; i-- > 0;) {
if (states[i] == FULL) {
keys[j++] = k[i];
}
}
return keys;
}
/**
* checks for the presence of val in the values of the map.
*
* @param val an int value
* @return a boolean value
*/
public boolean containsValue(int val) {
byte[] states = _states;
int[] vals = _values;
for (int i = vals.length; i-- > 0;) {
if (states[i] == FULL && val == vals[i]) {
return true;
}
}
return false;
}
/**
* checks for the present of key in the keys of the map.
*
* @param key an float value
* @return a boolean value
*/
public boolean containsKey(float key) {
return contains(key);
}
/**
* Executes procedure for each key in the map.
*
* @param procedure a TFloatProcedure value
* @return false if the loop over the keys terminated because
* the procedure returned false for some key.
*/
public boolean forEachKey(TFloatProcedure procedure) {
return forEach(procedure);
}
/**
* Executes procedure for each value in the map.
*
* @param procedure a TIntProcedure value
* @return false if the loop over the values terminated because
* the procedure returned false for some value.
*/
public boolean forEachValue(TIntProcedure procedure) {
byte[] states = _states;
int[] values = _values;
for (int i = values.length; i-- > 0;) {
if (states[i] == FULL && ! procedure.execute(values[i])) {
return false;
}
}
return true;
}
/**
* Executes procedure for each key/value entry in the
* map.
*
* @param procedure a TOFloatIntProcedure value
* @return false if the loop over the entries terminated because
* the procedure returned false for some entry.
*/
public boolean forEachEntry(TFloatIntProcedure procedure) {
byte[] states = _states;
float[] keys = _set;
int[] values = _values;
for (int i = keys.length; i-- > 0;) {
if (states[i] == FULL && ! procedure.execute(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.
*/
public boolean retainEntries(TFloatIntProcedure procedure) {
boolean modified = false;
byte[] states = _states;
float[] keys = _set;
int[] values = _values;
for (int i = keys.length; i-- > 0;) {
if (states[i] == FULL && ! procedure.execute(keys[i],values[i])) {
removeAt(i);
modified = true;
}
}
return modified;
}
/**
* Transform the values in this map using function.
*
* @param function a TIntFunction value
*/
public void transformValues(TIntFunction function) {
byte[] states = _states;
int[] values = _values;
for (int i = values.length; i-- > 0;) {
if (states[i] == FULL) {
values[i] = function.execute(values[i]);
}
}
}
/**
* Increments the primitive value mapped to key by 1
*
* @param key the key of the value to increment
* @return true if a mapping was found and modified.
*/
public boolean increment(float key) {
return adjustValue(key, (int)1);
}
/**
* Adjusts the primitive value mapped to key.
*
* @param key the key of the value to increment
* @param amount the amount to adjust the value by.
* @return true if a mapping was found and modified.
*/
public boolean adjustValue(float key, int amount) {
int index = index(key);
if (index < 0) {
return false;
} else {
_values[index] += amount;
return true;
}
}
private void writeObject(ObjectOutputStream stream)
throws IOException {
stream.defaultWriteObject();
// number of entries
stream.writeInt(_size);
SerializationProcedure writeProcedure = new SerializationProcedure(stream);
if (! forEachEntry(writeProcedure)) {
throw writeProcedure.exception;
}
}
private void readObject(ObjectInputStream stream)
throws IOException, ClassNotFoundException {
stream.defaultReadObject();
int size = stream.readInt();
setUp(size);
while (size-- > 0) {
float key = stream.readFloat();
int val = stream.readInt();
put(key, val);
}
}
} // TFloatIntHashMap
|