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/* -*- Mode: java; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Rhino code, released
* May 6, 1999.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1997-2000
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Norris Boyd
*
* Alternatively, the contents of this file may be used under the terms of
* the GNU General Public License Version 2 or later (the "GPL"), in which
* case the provisions of the GPL are applicable instead of those above. If
* you wish to allow use of your version of this file only under the terms of
* the GPL and not to allow others to use your version of this file under the
* MPL, indicate your decision by deleting the provisions above and replacing
* them with the notice and other provisions required by the GPL. If you do
* not delete the provisions above, a recipient may use your version of this
* file under either the MPL or the GPL.
*
* ***** END LICENSE BLOCK ***** */
package org.mozilla.javascript;
import java.lang.reflect.*;
/**
* Avoid loading classes unless they are used.
*
* This improves startup time and average memory usage.
*/
public final class LazilyLoadedCtor {
public LazilyLoadedCtor(ScriptableObject scope,
String ctorName, String className, boolean sealed)
{
this.className = className;
this.ctorName = ctorName;
this.sealed = sealed;
if (getter == null) {
Method[] methods = FunctionObject.getMethodList(getClass());
getter = FunctionObject.findSingleMethod(methods, "getProperty");
setter = FunctionObject.findSingleMethod(methods, "setProperty");
}
scope.defineProperty(ctorName, this, getter, setter,
ScriptableObject.DONTENUM);
}
public Object getProperty(ScriptableObject obj) {
synchronized (obj) {
if (!isReplaced) {
boolean removeOnError = false;
Class cl = Kit.classOrNull(className);
if (cl == null) {
removeOnError = true;
} else {
try {
ScriptableObject.defineClass(obj, cl, sealed);
isReplaced = true;
} catch (InvocationTargetException ex) {
Throwable target = ex.getTargetException();
if (target instanceof RuntimeException) {
throw (RuntimeException)target;
}
removeOnError = true;
} catch (RhinoException ex) {
removeOnError = true;
} catch (InstantiationException ex) {
removeOnError = true;
} catch (IllegalAccessException ex) {
removeOnError = true;
} catch (SecurityException ex) {
// Treat security exceptions as absence of object.
// They can be due to the following reasons:
// java.lang.RuntimePermission createClassLoader
removeOnError = true;
} catch (LinkageError ex) {
// No dependant classes
removeOnError = true;
}
}
if (removeOnError) {
obj.delete(ctorName);
return Scriptable.NOT_FOUND;
}
}
}
// Get just added object
return obj.get(ctorName, obj);
}
public Object setProperty(ScriptableObject obj, Object val) {
synchronized (obj) {
isReplaced = true;
return val;
}
}
private static Method getter, setter;
private String ctorName;
private String className;
private boolean sealed;
private boolean isReplaced;
}