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Posted to dev@commons.apache.org by fr...@apache.org on 2002/02/11 21:23:15 UTC
cvs commit: jakarta-commons-sandbox/simplestore/src/java/org/apache/commons/simplestore/cache/impl SynchronizedCache.java SoftRefMemoryCache.java
froehlich 02/02/11 12:23:15
Added: simplestore/src/java/org/apache/commons/simplestore/cache/impl
SynchronizedCache.java SoftRefMemoryCache.java
Log:
re-structured repository
Revision Changes Path
1.1 jakarta-commons-sandbox/simplestore/src/java/org/apache/commons/simplestore/cache/impl/SynchronizedCache.java
Index: SynchronizedCache.java
===================================================================
/*
* The Apache Software License, Version 1.1
*
*
* Copyright (c) 2001 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Apache Cocoon" and "Apache Software Foundation" must
* not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache",
* nor may "Apache" appear in their name, without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*/
package org.apache.commons.simplestore.cache.impl;
import org.apache.commons.simplestore.cache.Cache;
/**
*@author Juozas Baliuka <a href="mailto:baliuka@mwm.lt">
* baliuka@mwm.lt</a>
*@author Gerhard Froehlich <a href="mailto:g-froehlich@gmx.de">
* g-froehlich@gmx.de</a>
*@version $Id: SynchronizedCache.java,v 1.1 2002/02/11 20:23:15 froehlich Exp $
*/
final class SynchronizedCache implements Cache {
private Cache mCache;
/**
* Creates new SynchronizedCache
*
*@param cache
*/
public SynchronizedCache(Cache cache) {
if (cache == null) {
throw new NullPointerException();
}
this.mCache = cache;
}
/**
* Get the object associated to the given unique key.
*
*@param key the Key Object
*@return requested object or null
*/
public Object get(Object key) {
synchronized (mCache) {
return mCache.get(key);
}
}
/**
* Cache the object associated to the given unique key.
*
*@param key the key object
*@param value the value Object
*/
public void put(Object key, Object value) {
synchronized (mCache) {
mCache.put(key, value);
}
}
}
1.1 jakarta-commons-sandbox/simplestore/src/java/org/apache/commons/simplestore/cache/impl/SoftRefMemoryCache.java
Index: SoftRefMemoryCache.java
===================================================================
/*
* The Apache Software License, Version 1.1
*
*
* Copyright (c) 2001 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Apache Cocoon" and "Apache Software Foundation" must
* not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache",
* nor may "Apache" appear in their name, without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*/
package org.apache.commons.simplestore.cache.impl;
import org.apache.commons.simplestore.cache.Cache;
import java.lang.ref.ReferenceQueue;
import java.lang.ref.SoftReference;
import java.util.Map;
/**
*@author Juozas Baliuka <a href="mailto:baliuka@mwm.lt">
* baliuka@mwm.lt</a>
*@author Gerhard Froehlich <a href="mailto:g-froehlich@gmx.de">
* g-froehlich@gmx.de</a>
*@version $Id: SoftRefMemoryCache.java,v 1.1 2002/02/11 20:23:15 froehlich Exp $
*/
public class SoftRefMemoryCache implements Cache {
private static boolean DEBUG = true;
private int m_current = 0;
private int m_maxStrongRefCount;
private Map m_map;
private Object[] m_strongRefs;
private ReferenceQueue m_queue = new ReferenceQueue();
/**
* Creates new SoftRefMemoryCache
*
*@param map
*@param maxStrongRefCount
*/
protected SoftRefMemoryCache(Map map, int maxStrongRefCount) {
this.m_map = map;
if (maxStrongRefCount < 0) {
throw new java.lang.IllegalArgumentException();
}
this.m_maxStrongRefCount = maxStrongRefCount;
if (maxStrongRefCount > 0) {
m_strongRefs = new Object[maxStrongRefCount];
}
}
public static Cache getInstance(Map map, int maxStrongRef) {
return new SynchronizedCache(new SoftRefMemoryCache(map, maxStrongRef));
}
/**
* Get the object associated to the given unique key.
*
*@param key the Key Object
*@return requested object or null
*/
public Object get(Object key) {
removeSoftRef();
Object object = null;
SoftRef ref = (SoftRef) m_map.get(key);
if (ref != null) {
object = ref.get();
}
addStrongRef(object);
return object;
}
/**
* Cache the object associated to the given unique key.
*
*@param key the key object
*@param value the value Object
*/
public void put(Object key, Object object) {
removeSoftRef();
internalStoreObject(key, object);
}
private SoftRef makeValue(Object key, Object value, ReferenceQueue queue) {
return new SoftRef(key, value, queue);
}
// remove unused keys
private void removeSoftRef() {
SoftRef ref = (SoftRef) m_queue.poll();
while (ref != null) {
m_map.remove(ref.key);
if (DEBUG) {
System.out.println("Key " + ref.key + " removed from Reference queue, map size is " + m_map.size());
}
ref = (SoftRef) m_queue.poll();
}
}
private void addStrongRef(Object object) {
if (m_strongRefs != null) {
m_strongRefs[(m_current++) % m_maxStrongRefCount] = object;
}
}
private void internalStoreObject(Object key, Object object) {
SoftRef ref = makeValue(key, object, m_queue);
addStrongRef(ref.get());
m_map.put(key, ref);
}
static class SoftRef extends SoftReference {
Object key;
private SoftRef(Object key, Object object, ReferenceQueue queue) {
super(object, queue);
this.key = key;
}
}
}
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