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AspectJ tools most notably contains the AspectJ compiler (AJC). AJC applies aspects to Java classes during
compilation, fully replacing Javac for plain Java classes and also compiling native AspectJ or annotation-based
@AspectJ syntax. Furthermore, AJC can weave aspects into existing class files in a post-compile binary weaving step.
This library is a superset of AspectJ weaver and hence also of AspectJ runtime.
/*******************************************************************************
* Copyright (c) 2018 IBM Corporation and others.
*
* This program and the accompanying materials
* are made available under the terms of the Eclipse Public License 2.0
* which accompanies this distribution, and is available at
* https://www.eclipse.org/legal/epl-2.0/
*
* SPDX-License-Identifier: EPL-2.0
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.aspectj.org.eclipse.jdt.internal.compiler.util;
/**
* Hashtable for Integer keys.
*/
public final class HashtableOfInteger {
// to avoid using Enumerations, walk the individual tables skipping nulls
public Integer keyTable[];
public Object valueTable[];
public int elementSize; // number of elements in the table
int threshold;
public HashtableOfInteger() {
this(13);
}
public HashtableOfInteger(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 Integer[extraRoom];
this.valueTable = new Object[extraRoom];
}
public void clear() {
for (int i = this.keyTable.length; --i >= 0;) {
this.keyTable[i] = null;
this.valueTable[i] = null;
}
this.elementSize = 0;
}
@Override
public Object clone() throws CloneNotSupportedException {
HashtableOfInteger result = (HashtableOfInteger) super.clone();
result.elementSize = this.elementSize;
result.threshold = this.threshold;
int length = this.keyTable.length;
result.keyTable = new Integer[length];
System.arraycopy(this.keyTable, 0, result.keyTable, 0, length);
length = this.valueTable.length;
result.valueTable = new Object[length];
System.arraycopy(this.valueTable, 0, result.valueTable, 0, length);
return result;
}
public boolean containsKey(int key) {
Integer intKey = Integer.valueOf(key);
int length = this.keyTable.length,
index = intKey.hashCode() % length;
Integer currentKey;
while ((currentKey = this.keyTable[index]) != null) {
if (currentKey.equals(intKey))
return true;
if (++index == length) {
index = 0;
}
}
return false;
}
public Object get(int key) {
Integer intKey = Integer.valueOf(key);
int length = this.keyTable.length,
index = intKey.hashCode() % length;
Integer currentKey;
while ((currentKey = this.keyTable[index]) != null) {
if (currentKey.equals(intKey))
return this.valueTable[index];
if (++index == length) {
index = 0;
}
}
return null;
}
public Object put(int key, Object value) {
Integer intKey = Integer.valueOf(key);
int length = this.keyTable.length,
index = intKey.hashCode() % length;
Integer currentKey;
while ((currentKey = this.keyTable[index]) != null) {
if (currentKey.equals(intKey))
return this.valueTable[index] = value;
if (++index == length) {
index = 0;
}
}
this.keyTable[index] = intKey;
this.valueTable[index] = value;
// assumes the threshold is never equal to the size of the table
if (++this.elementSize > this.threshold)
rehash();
return value;
}
/**
* Put a value at the index of the given using the local hash code computation.
*
* Note that this is an unsafe put as there's no prior verification whether
* the given key already exists in the table or not.
*
* @param key The key of the table entry
* @param value The value of the table entry
*/
public void putUnsafely(int key, Object value) {
Integer intKey = Integer.valueOf(key);
int length = this.keyTable.length,
index = intKey.hashCode() % length;
while (this.keyTable[index] != null) {
if (++index == length) {
index = 0;
}
}
this.keyTable[index] = intKey;
this.valueTable[index] = value;
// assumes the threshold is never equal to the size of the table
if (++this.elementSize > this.threshold) {
rehash();
}
}
public Object removeKey(int key) {
Integer intKey = Integer.valueOf(key);
int length = this.keyTable.length,
index = intKey.hashCode() % length;
Integer currentKey;
while ((currentKey = this.keyTable[index]) != null) {
if (currentKey.equals(intKey)) {
Object value = this.valueTable[index];
this.elementSize--;
this.keyTable[index] = null;
this.valueTable[index] = null;
rehash();
return value;
}
if (++index == length) {
index = 0;
}
}
return null;
}
private void rehash() {
HashtableOfInteger newHashtable = new HashtableOfInteger(this.elementSize * 2); // double the number of expected elements
Integer currentKey;
for (int i = this.keyTable.length; --i >= 0;)
if ((currentKey = this.keyTable[i]) != null)
newHashtable.putUnsafely(currentKey, this.valueTable[i]);
this.keyTable = newHashtable.keyTable;
this.valueTable = newHashtable.valueTable;
this.threshold = newHashtable.threshold;
}
public int size() {
return this.elementSize;
}
@Override
public String toString() {
String s = ""; //$NON-NLS-1$
Object object;
for (int i = 0, length = this.valueTable.length; i < length; i++)
if ((object = this.valueTable[i]) != null)
s += this.keyTable[i] + " -> " + object.toString() + "\n"; //$NON-NLS-2$ //$NON-NLS-1$
return s;
}
}