| /* |
| * Copyright (c) 2005, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code 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 General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| 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>>(); |
| } |