/*******************************************************************************
* Copyright (c) 2000, 2005 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.swt.widgets;
import org.eclipse.swt.*;
import org.eclipse.swt.internal.SWTEventListener;
/**
* Instances of this class implement a simple
* look up mechanism that maps an event type
* to a listener. Muliple listeners for the
* same event type are supported.
*/
class EventTable {
int[] types;
Listener[] listeners;
int level;
public void hook(int eventType, Listener listener) {
if (types == null)
types = new int[4];
if (listeners == null)
listeners = new Listener[4];
int length = types.length, index = length - 1;
while (index >= 0) {
if (types[index] != 0)
break;
--index;
}
index++;
if (index == length) {
int[] newTypes = new int[length + 4];
System.arraycopy(types, 0, newTypes, 0, length);
types = newTypes;
Listener[] newListeners = new Listener[length + 4];
System.arraycopy(listeners, 0, newListeners, 0, length);
listeners = newListeners;
}
types[index] = eventType;
listeners[index] = listener;
}
public boolean hooks(int eventType) {
if (types == null)
return false;
for (int i = 0; i < types.length; i++) {
if (types[i] == eventType)
return true;
}
return false;
}
public void sendEvent(Event event) {
if (types == null)
return;
level += level >= 0 ? 1 : -1;
try {
for (int i = 0; i < types.length; i++) {
if (event.type == SWT.None)
return;
if (types[i] == event.type) {
Listener listener = listeners[i];
if (listener != null)
listener.handleEvent(event);
}
}
} finally {
boolean compact = level < 0;
level -= level >= 0 ? 1 : -1;
if (compact && level == 0) {
int index = 0;
for (int i = 0; i < types.length; i++) {
if (types[i] != 0) {
types[index] = types[i];
listeners[index] = listeners[i];
index++;
}
}
for (int i = index; i < types.length; i++) {
types[i] = 0;
listeners[i] = null;
}
}
}
}
public int size() {
if (types == null)
return 0;
int count = 0;
for (int i = 0; i < types.length; i++) {
if (types[i] != 0)
count++;
}
return count;
}
void remove(int index) {
if (level == 0) {
int end = types.length - 1;
System.arraycopy(types, index + 1, types, index, end
- index);
System.arraycopy(listeners, index + 1, listeners, index,
end - index);
index = end;
} else {
if (level > 0)
level = -level;
}
types[index] = 0;
listeners[index] = null;
}
public void unhook(int eventType, Listener listener) {
if (types == null)
return;
for (int i = 0; i < types.length; i++) {
if (types[i] == eventType && listeners[i] == listener) {
remove(i);
return;
}
}
}
public void unhook(int eventType, SWTEventListener listener) {
if (types == null)
return;
for (int i = 0; i < types.length; i++) {
if (types[i] == eventType) {
if (listeners[i] instanceof TypedListener) {
TypedListener typedListener = (TypedListener) listeners[i];
if (typedListener.getEventListener() == listener) {
remove(i);
return;
}
}
}
}
}
void releaseResource() {
if (listeners != null) {
for (int i = 0; i < listeners.length; i++) {
listeners[i] = null;
}
listeners = null;
}
}
}
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