/*
* @(#)DescriptorCache.java 1.2 05/11/17
*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
package com.sun.jmx.mbeanserver;
import java.lang.ref.WeakReference;
import java.util.WeakHashMap;
import javax.management.Descriptor;
import javax.management.ImmutableDescriptor;
import javax.management.JMX;
public class DescriptorCache {
private DescriptorCache() {
}
static DescriptorCache getInstance() {
return instance;
}
public static DescriptorCache getInstance(JMX proof) {
if (proof != null)
return instance;
else
return null;
}
public ImmutableDescriptor get(ImmutableDescriptor descriptor) {
WeakReference<ImmutableDescriptor> wr = map.get(descriptor);
ImmutableDescriptor got = (wr == null) ? null : wr.get();
if (got != null)
return got;
map.put(descriptor, new WeakReference<ImmutableDescriptor>(descriptor));
return descriptor;
}
public ImmutableDescriptor union(Descriptor... descriptors) {
return get(ImmutableDescriptor.union(descriptors));
}
private final static DescriptorCache instance = new DescriptorCache();
private final WeakHashMap<ImmutableDescriptor,
WeakReference<ImmutableDescriptor>>
map = new WeakHashMap<ImmutableDescriptor,
WeakReference<ImmutableDescriptor>>();
}