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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) 2000, 2006 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.eclipse.core.internal.registry;
import java.io.*;
/**
* Hashtable of {String --> int }
*/
public final class HashtableOfStringAndInt implements Cloneable {
public static final int MISSING_ELEMENT = Integer.MIN_VALUE;
// to avoid using Enumerations, walk the individual tables skipping nulls
private String keyTable[];
private int valueTable[];
private int elementSize; // number of elements in the table
private int threshold;
private static final float GROWTH_FACTOR = 1.33f;
public HashtableOfStringAndInt() {
this(13);
}
public HashtableOfStringAndInt(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 String[extraRoom];
this.valueTable = new int[extraRoom];
}
@Override
public Object clone() throws CloneNotSupportedException {
throw new CloneNotSupportedException();
// HashtableOfStringAndInt result = (HashtableOfStringAndInt) super.clone();
// result.elementSize = this.elementSize;
// result.threshold = this.threshold;
//
// int length = this.keyTable.length;
// result.keyTable = new char[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(String key) {
int index = (key.hashCode() & 0x7FFFFFFF) % valueTable.length;
int keyLength = key.length();
String currentKey;
while ((currentKey = keyTable[index]) != null) {
if (currentKey.length() == keyLength && currentKey.equals(key))
return true;
index = (index + 1) % keyTable.length;
}
return false;
}
public int get(String key) {
int index = (key.hashCode() & 0x7FFFFFFF) % valueTable.length;
int keyLength = key.length();
String currentKey;
while ((currentKey = keyTable[index]) != null) {
if (currentKey.length() == keyLength && currentKey.equals(key))
return valueTable[index];
index = (index + 1) % keyTable.length;
}
return MISSING_ELEMENT;
}
public int put(String key, int value) {
int index = (key.hashCode() & 0x7FFFFFFF) % valueTable.length;
int keyLength = key.length();
String currentKey;
while ((currentKey = keyTable[index]) != null) {
if (currentKey.length() == keyLength && currentKey.equals(key))
return valueTable[index] = value;
index = (index + 1) % keyTable.length;
}
keyTable[index] = key;
valueTable[index] = value;
// assumes the threshold is never equal to the size of the table
if (++elementSize > threshold)
rehash();
return value;
}
public int removeKey(String key) {
int index = (key.hashCode() & 0x7FFFFFFF) % valueTable.length;
int keyLength = key.length();
String currentKey;
while ((currentKey = keyTable[index]) != null) {
if (currentKey.length() == keyLength && currentKey.equals(key)) {
int value = valueTable[index];
elementSize--;
keyTable[index] = null;
valueTable[index] = MISSING_ELEMENT;
rehash();
return value;
}
index = (index + 1) % keyTable.length;
}
return MISSING_ELEMENT;
}
private void rehash() {
HashtableOfStringAndInt newHashtable = new HashtableOfStringAndInt((int) (elementSize * GROWTH_FACTOR));
String currentKey;
for (int i = keyTable.length; --i >= 0;)
if ((currentKey = keyTable[i]) != null)
newHashtable.put(currentKey, valueTable[i]);
this.keyTable = newHashtable.keyTable;
this.valueTable = newHashtable.valueTable;
this.threshold = newHashtable.threshold;
}
public int size() {
return elementSize;
}
@Override
public String toString() {
String s = ""; //$NON-NLS-1$
int object;
for (int i = 0, length = valueTable.length; i < length; i++)
if ((object = valueTable[i]) != MISSING_ELEMENT)
s += new String(keyTable[i]) + " -> " + object + "\n"; //$NON-NLS-2$ //$NON-NLS-1$
return s;
}
public int[] getValues() {
int keyTableLength = keyTable.length;
int[] result = new int[size()];
int j = 0;
for (int i = 0; i < keyTableLength; i++) {
if (keyTable[i] != null)
result[j++] = valueTable[i];
}
return result;
}
public void save(DataOutputStream out) throws IOException {
out.writeInt(elementSize);
int tableSize = keyTable.length;
out.writeInt(tableSize);
out.writeInt(threshold);
for (int i = 0; i < tableSize; i++) {
writeStringOrNull(keyTable[i], out);
out.writeInt(valueTable[i]);
}
}
/**
* Filtered save: outputs only elements with values not in the excluded list.
*/
public void save(DataOutputStream out, RegistryObjectManager objectManager) throws IOException {
HashtableOfStringAndInt filteredHashtable = new HashtableOfStringAndInt((int) (elementSize * GROWTH_FACTOR));
String currentKey;
for (int i = keyTable.length; --i >= 0;)
if ((currentKey = keyTable[i]) != null && objectManager.shouldPersist(valueTable[i]))
filteredHashtable.put(currentKey, valueTable[i]);
filteredHashtable.save(out);
}
public void load(DataInputStream in) throws IOException {
elementSize = in.readInt();
int tableSize = in.readInt();
threshold = in.readInt();
boolean fastMode = true;
if (((double) tableSize / elementSize) < GROWTH_FACTOR) {
keyTable = new String[(int) (elementSize * GROWTH_FACTOR)];
valueTable = new int[(int) (elementSize * GROWTH_FACTOR)];
elementSize = 0;
fastMode = false;
} else {
keyTable = new String[tableSize];
valueTable = new int[tableSize];
}
for (int i = 0; i < tableSize; i++) {
String key = readStringOrNull(in);
int value = in.readInt();
if (fastMode) {
keyTable[i] = key;
valueTable[i] = value;
} else {
if (key != null)
put(key, value);
}
}
}
private static final byte NULL = 0;
private static final byte OBJECT = 1;
private void writeStringOrNull(String string, DataOutputStream out) throws IOException {
if (string == null)
out.writeByte(NULL);
else {
out.writeByte(OBJECT);
out.writeUTF(string);
}
}
private String readStringOrNull(DataInputStream in) throws IOException {
byte type = in.readByte();
if (type == NULL)
return null;
return in.readUTF();
}
}