/*******************************************************************************
* 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.core.util;
import org.eclipse.jdt.core.compiler.CharOperation;
/**
* HashSet of char[][]
*/
public final class HashSetOfCharArrayArray implements Cloneable {
// to avoid using Enumerations, walk the individual tables skipping nulls
public char[][][] set;
public int elementSize; // number of elements in the table
int threshold;
public HashSetOfCharArrayArray() {
this(13);
}
public HashSetOfCharArrayArray(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.set= new char[extraRoom][][];
}
public Object clone() throws CloneNotSupportedException {
HashSetOfCharArrayArray result= (HashSetOfCharArrayArray)super.clone();
result.elementSize= this.elementSize;
result.threshold= this.threshold;
int length= this.set.length;
result.set= new char[length][][];
System.arraycopy(this.set, 0, result.set, 0, length);
return result;
}
public boolean contains(char[][] array) {
int length= this.set.length;
int index= hashCode(array) % length;
int arrayLength= array.length;
char[][] currentArray;
while ((currentArray= this.set[index]) != null) {
if (currentArray.length == arrayLength && CharOperation.equals(currentArray, array))
return true;
if (++index == length) {
index= 0;
}
}
return false;
}
private int hashCode(char[][] element) {
return hashCode(element, element.length);
}
private int hashCode(char[][] element, int length) {
int hash= 0;
for (int i= length - 1; i >= 0; i--)
hash= Util.combineHashCodes(hash, CharOperation.hashCode(element[i]));
return hash & 0x7FFFFFFF;
}
public char[][] add(char[][] array) {
int length= this.set.length;
int index= hashCode(array) % length;
int arrayLength= array.length;
char[][] currentArray;
while ((currentArray= this.set[index]) != null) {
if (currentArray.length == arrayLength && CharOperation.equals(currentArray, array))
return this.set[index]= array;
if (++index == length) {
index= 0;
}
}
this.set[index]= array;
// assumes the threshold is never equal to the size of the table
if (++this.elementSize > this.threshold)
rehash();
return array;
}
public char[][] remove(char[][] array) {
int length= this.set.length;
int index= hashCode(array) % length;
int arrayLength= array.length;
char[][] currentArray;
while ((currentArray= this.set[index]) != null) {
if (currentArray.length == arrayLength && CharOperation.equals(currentArray, array)) {
char[][] existing= this.set[index];
this.elementSize--;
this.set[index]= null;
rehash();
return existing;
}
if (++index == length) {
index= 0;
}
}
return null;
}
private void rehash() {
HashSetOfCharArrayArray newHashSet= new HashSetOfCharArrayArray(this.elementSize * 2); // double the number of expected elements
char[][] currentArray;
for (int i= this.set.length; --i >= 0;)
if ((currentArray= this.set[i]) != null)
newHashSet.add(currentArray);
this.set= newHashSet.set;
this.threshold= newHashSet.threshold;
}
public int size() {
return this.elementSize;
}
public String toString() {
StringBuffer buffer= new StringBuffer();
for (int i= 0, length= this.set.length; i < length; i++) {
char[][] arrayArray= this.set[i];
if (arrayArray != null) {
buffer.append("{"); //$NON-NLS-1$
for (int j= 0, length2= arrayArray.length; j < length2; j++) {
char[] array= arrayArray[j];
buffer.append('{');
for (int k= 0, length3= array.length; k < length3; k++) {
buffer.append('\'');
buffer.append(array[k]);
buffer.append('\'');
if (k != length3 - 1)
buffer.append(", "); //$NON-NLS-1$
}
buffer.append('}');
if (j != length2 - 1)
buffer.append(", "); //$NON-NLS-1$
}
buffer.append("}"); //$NON-NLS-1$
if (i != length - 1)
buffer.append('\n');
}
}
return buffer.toString();
}
}