org.eclipse.jdt.internal.compiler.util.HashtableOfObjectToIntArray Maven / Gradle / Ivy
/*******************************************************************************
* Copyright (c) 2000, 2009 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.jdt.internal.compiler.util;
/**
* Hashtable of {Object --> int[] }
*/
public final class HashtableOfObjectToIntArray implements Cloneable {
// to avoid using Enumerations, walk the individual tables skipping nulls
public Object[] keyTable;
public int[][] valueTable;
public int elementSize; // number of elements in the table
int threshold;
public HashtableOfObjectToIntArray() {
this(13);
}
public HashtableOfObjectToIntArray(int size) {
this.elementSize = 0;
this.threshold = size; // size represents the expected number of elements
int extraRoom = (int) (size * 1.75f);
if (this.threshold == extraRoom)
extraRoom++;
this.keyTable = new Object[extraRoom];
this.valueTable = new int[extraRoom][];
}
public Object clone() throws CloneNotSupportedException {
HashtableOfObjectToIntArray result = (HashtableOfObjectToIntArray) super.clone();
result.elementSize = this.elementSize;
result.threshold = this.threshold;
int length = this.keyTable.length;
result.keyTable = new Object[length];
System.arraycopy(this.keyTable, 0, result.keyTable, 0, length);
length = this.valueTable.length;
result.valueTable = new int[length][];
System.arraycopy(this.valueTable, 0, result.valueTable, 0, length);
return result;
}
public boolean containsKey(Object key) {
int length = this.keyTable.length,
index = (key.hashCode()& 0x7FFFFFFF) % length;
Object currentKey;
while ((currentKey = this.keyTable[index]) != null) {
if (currentKey.equals(key))
return true;
if (++index == length) {
index = 0;
}
}
return false;
}
public int[] get(Object key) {
int length = this.keyTable.length,
index = (key.hashCode()& 0x7FFFFFFF) % length;
Object currentKey;
while ((currentKey = this.keyTable[index]) != null) {
if (currentKey.equals(key))
return this.valueTable[index];
if (++index == length) {
index = 0;
}
}
return null;
}
public void keysToArray(Object[] array) {
int index = 0;
for (int i=0, length=this.keyTable.length; i this.threshold)
rehash();
return value;
}
public int[] removeKey(Object key) {
int length = this.keyTable.length,
index = (key.hashCode()& 0x7FFFFFFF) % length;
Object currentKey;
while ((currentKey = this.keyTable[index]) != null) {
if (currentKey.equals(key)) {
int[] value = this.valueTable[index];
this.elementSize--;
this.keyTable[index] = null;
rehash();
return value;
}
if (++index == length) {
index = 0;
}
}
return null;
}
private void rehash() {
HashtableOfObjectToIntArray newHashtable = new HashtableOfObjectToIntArray(this.elementSize * 2); // double the number of expected elements
Object currentKey;
for (int i = this.keyTable.length; --i >= 0;)
if ((currentKey = this.keyTable[i]) != null)
newHashtable.put(currentKey, this.valueTable[i]);
this.keyTable = newHashtable.keyTable;
this.valueTable = newHashtable.valueTable;
this.threshold = newHashtable.threshold;
}
public int size() {
return this.elementSize;
}
public String toString() {
StringBuffer buffer = new StringBuffer();
Object key;
for (int i = 0, length = this.keyTable.length; i < length; i++) {
if ((key = this.keyTable[i]) != null) {
buffer.append(key).append(" -> "); //$NON-NLS-1$
int[] ints = this.valueTable[i];
buffer.append('[');
if (ints != null) {
for (int j = 0, max = ints.length; j < max; j++) {
if (j > 0) {
buffer.append(',');
}
buffer.append(ints[j]);
}
}
buffer.append("]\n"); //$NON-NLS-1$
}
}
return String.valueOf(buffer);
}
}