org.eclipse.jdt.internal.compiler.util.HashtableOfPackage Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of ecj Show documentation
This is Eclipse JDT Core Batch Compiler used by Scout SDK
The newest version!
/*******************************************************************************
 * 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;

import org.eclipse.jdt.core.compiler.CharOperation;
import org.eclipse.jdt.internal.compiler.lookup.PackageBinding;

public final class HashtableOfPackage {
	// to avoid using Enumerations, walk the individual tables skipping nulls
	public char[] keyTable[];
	public PackageBinding valueTable[];

	public int elementSize; // number of elements in the table
	int threshold;
public HashtableOfPackage() {
	this(3); // usually not very large
}
public HashtableOfPackage(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 char[extraRoom][];
	this.valueTable = new PackageBinding[extraRoom];
}
public boolean containsKey(char[] key) {
	int length = this.keyTable.length,
		index = CharOperation.hashCode(key) % length;
	int keyLength = key.length;
	char[] currentKey;
	while ((currentKey = this.keyTable[index]) != null) {
		if (currentKey.length == keyLength && CharOperation.equals(currentKey, key))
			return true;
		if (++index == length) {
			index = 0;
		}
	}
	return false;
}
public PackageBinding get(char[] key) {
	int length = this.keyTable.length,
		index = CharOperation.hashCode(key) % length;
	int keyLength = key.length;
	char[] currentKey;
	while ((currentKey = this.keyTable[index]) != null) {
		if (currentKey.length == keyLength && CharOperation.equals(currentKey, key))
			return this.valueTable[index];
		if (++index == length) {
			index = 0;
		}
	}
	return null;
}
public PackageBinding put(char[] key, PackageBinding value) {
	int length = this.keyTable.length,
		index = CharOperation.hashCode(key) % length;
	int keyLength = key.length;
	char[] currentKey;
	while ((currentKey = this.keyTable[index]) != null) {
		if (currentKey.length == keyLength && CharOperation.equals(currentKey, key))
			return this.valueTable[index] = value;
		if (++index == length) {
			index = 0;
		}
	}
	this.keyTable[index] = key;
	this.valueTable[index] = value;

	// assumes the threshold is never equal to the size of the table
	if (++this.elementSize > this.threshold)
		rehash();
	return value;
}
private void rehash() {
	HashtableOfPackage newHashtable = new HashtableOfPackage(this.elementSize * 2); // double the number of expected elements
	char[] 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() {
	String s = ""; //$NON-NLS-1$
	PackageBinding pkg;
	for (int i = 0, length = this.valueTable.length; i < length; i++)
		if ((pkg = this.valueTable[i]) != null)
			s += pkg.toString() + "\n"; //$NON-NLS-1$
	return s;
}
}