/* Copyright 2004 The Apache Software Foundation
*
* Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
// Revised from xmlbeans
import java.util.HashMap;
import java.lang.ref.SoftReference;
/**
* @author Cezar Andrei (cezar.andrei at bea.com)
* Date: Apr 26, 2005
*/
public class SoftCache
{
private HashMap map = new HashMap();
public Object get(Object key)
{
SoftReference softRef = (SoftReference)map.get(key);
if (softRef==null)
return null;
return softRef.get();
}
public Object put(Object key, Object value)
{
SoftReference softRef = (SoftReference)map.put(key, new SoftReference(value));
if (softRef==null)
return null;
Object oldValue = softRef.get();
softRef.clear();
return oldValue;
}
public Object remove(Object key)
{
SoftReference softRef = (SoftReference)map.remove(key);
if (softRef==null)
return null;
Object oldValue = softRef.get();
softRef.clear();
return oldValue;
}
}
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