/*******************************************************************************
* Copyright (c) 2000, 2004 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Common Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/cpl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.jdt.internal.compiler.codegen;
public class FloatCache {
private float keyTable[];
private int valueTable[];
private int elementSize;
/**
* Constructs a new, empty hashtable. A default capacity and
* load factor is used. Note that the hashtable will automatically
* grow when it gets full.
*/
public FloatCache() {
this(13);
}
/**
* Constructs a new, empty hashtable with the specified initial
* capacity.
* @param initialCapacity int
* the initial number of buckets
*/
public FloatCache(int initialCapacity) {
elementSize = 0;
keyTable = new float[initialCapacity];
valueTable = new int[initialCapacity];
}
/**
* Clears the hash table so that it has no more elements in it.
*/
public void clear() {
for (int i = keyTable.length; --i >= 0;) {
keyTable[i] = 0.0f;
valueTable[i] = 0;
}
elementSize = 0;
}
/** Returns true if the collection contains an element for the key.
*
* @param key float
the key that we are looking for
* @return boolean
*/
public boolean containsKey(float key) {
if (key == 0.0f) {
for (int i = 0, max = elementSize; i < max; i++) {
if (keyTable[i] == 0.0f) {
int value1 = Float.floatToIntBits(key);
int value2 = Float.floatToIntBits(keyTable[i]);
if (value1 == -2147483648 && value2 == -2147483648)
return true;
if (value1 == 0 && value2 == 0)
return true;
}
}
} else {
for (int i = 0, max = elementSize; i < max; i++) {
if (keyTable[i] == key) {
return true;
}
}
}
return false;
}
/** Gets the object associated with the specified key in the
* hashtable.
* @param key float
the specified key
* @return int the element for the key or -1 if the key is not
* defined in the hash table.
*/
public int get(float key) {
if (key == 0.0f) {
for (int i = 0, max = elementSize; i < max; i++) {
if (keyTable[i] == 0.0f) {
int value1 = Float.floatToIntBits(key);
int value2 = Float.floatToIntBits(keyTable[i]);
if (value1 == -2147483648 && value2 == -2147483648)
return valueTable[i];
if (value1 == 0 && value2 == 0)
return valueTable[i];
}
}
} else {
for (int i = 0, max = elementSize; i < max; i++) {
if (keyTable[i] == key) {
return valueTable[i];
}
}
}
return -1;
}
/**
* Puts the specified element into the hashtable, using the specified
* key. The element may be retrieved by doing a get() with the same key.
*
* @param key float
the specified key in the hashtable
* @param value int
the specified element
* @return int value
*/
public int put(float key, int value) {
if (elementSize == keyTable.length) {
// resize
System.arraycopy(keyTable, 0, (keyTable = new float[elementSize * 2]), 0, elementSize);
System.arraycopy(valueTable, 0, (valueTable = new int[elementSize * 2]), 0, elementSize);
}
keyTable[elementSize] = key;
valueTable[elementSize] = value;
elementSize++;
return value;
}
/**
* Converts to a rather lengthy String.
*
* @return String the ascii representation of the receiver
*/
public String toString() {
int max = elementSize;
StringBuffer buf = new StringBuffer();
buf.append("{"); //$NON-NLS-1$
for (int i = 0; i < max; ++i) {
if ((keyTable[i] != 0) || ((keyTable[i] == 0) && (valueTable[i] != 0))) {
buf.append(keyTable[i]).append("->").append(valueTable[i]); //$NON-NLS-1$
}
if (i < max) {
buf.append(", "); //$NON-NLS-1$
}
}
buf.append("}"); //$NON-NLS-1$
return buf.toString();
}
}