/*
* GNU LESSER GENERAL PUBLIC LICENSE Copyright (C) 2006 The Lobo Project
*
* This library is free software; you can redistribute it and/or modify it under
* the terms of the GNU Lesser General Public License as published by the Free
* Software Foundation; either version 2.1 of the License, or (at your option)
* any later version.
*
* This library is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
* details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* Contact info: lobochief@users.sourceforge.net
*/
package com.nvarghese.beowulf.common.cobra.js;
import java.lang.ref.WeakReference;
import java.util.Map;
import java.util.WeakHashMap;
public class JavaClassWrapperFactory {
private static JavaClassWrapperFactory instance;
private final Map classWrappers = new WeakHashMap();
private JavaClassWrapperFactory() {
}
public static JavaClassWrapperFactory getInstance() {
if (instance == null) {
synchronized (JavaClassWrapperFactory.class) {
if (instance == null) {
instance = new JavaClassWrapperFactory();
}
}
}
return instance;
}
public JavaClassWrapper getClassWrapper(final Class clazz) {
synchronized (this) {
// WeakHashMaps where the value refers to
// the key will retain keys. Must make it
// refer to the value weakly too.
WeakReference jcwr = (WeakReference) this.classWrappers.get(clazz);
JavaClassWrapper jcw = null;
if (jcwr != null) {
jcw = (JavaClassWrapper) jcwr.get();
}
if (jcw == null) {
jcw = new JavaClassWrapper(clazz);
this.classWrappers.put(clazz, new WeakReference(jcw));
}
return jcw;
}
}
}