package org.apache.torque.manager;
/*
* Copyright 2001-2004 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.
*/
import java.io.Serializable;
import java.util.HashMap;
import java.util.Map;
import org.apache.commons.pool.ObjectPool;
import org.apache.commons.pool.impl.StackObjectPool;
import org.apache.jcs.access.GroupCacheAccess;
import org.apache.jcs.access.exception.CacheException;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.torque.TorqueException;
/**
* This class provides a cache for convenient storage of method
* results.
*
* @author <a href="mailto:jmcnally@collab.net">John McNally</a>
* @version $Id: MethodResultCache.java,v 1.19.2.2 2004/05/20 04:36:06 seade Exp $
*/
public class MethodResultCache
{
private ObjectPool pool;
private GroupCacheAccess jcsCache;
private Map groups;
/** Logging */
private static Log log = LogFactory.getLog(MethodResultCache.class);
public MethodResultCache(GroupCacheAccess cache)
throws TorqueException
{
this.jcsCache = cache;
groups = new HashMap();
pool = new StackObjectPool(new MethodCacheKey.Factory(), 10000);
}
/**
* Allows subclasses to have ctors that do not require a cache.
* This is used by NullMethodResultCache which has no-op versions
* of all methods.
*/
protected MethodResultCache()
{
}
public void clear()
{
if (jcsCache != null)
{
try
{
jcsCache.remove();
groups.clear();
}
catch (CacheException ce)
{
log.error(new TorqueException(
"Could not clear cache due to internal JCS error.", ce));
}
}
}
protected Object getImpl(MethodCacheKey key)
{
Object result = null;
if (jcsCache != null)
{
synchronized (this)
{
result = jcsCache.getFromGroup(key, key.getGroupKey());
}
}
if (result != null)
{
if (log.isDebugEnabled())
{
log.debug("MethodResultCache saved expensive operation: " + key);
}
}
return result;
}
protected Object putImpl(MethodCacheKey key, Object value)
throws TorqueException
{
//register the group, if this is the first occurrence
String group = key.getGroupKey();
if (!groups.containsKey(group))
{
groups.put(group, null);
}
Object old = null;
if (jcsCache != null)
{
try
{
synchronized (this)
{
old = jcsCache.getFromGroup(key, group);
jcsCache.putInGroup(key, group, value);
}
}
catch (CacheException ce)
{
throw new TorqueException
("Could not cache due to internal JCS error", ce);
}
}
return old;
}
protected Object removeImpl(MethodCacheKey key)
throws TorqueException
{
Object old = null;
if (jcsCache != null)
{
synchronized (this)
{
old = jcsCache.getFromGroup(key, key.getGroupKey());
jcsCache.remove(key, key.getGroupKey());
}
}
return old;
}
public Object get(Serializable instanceOrClass, String method)
{
Object result = null;
if (jcsCache != null)
{
try
{
MethodCacheKey key = (MethodCacheKey) pool.borrowObject();
key.init(instanceOrClass, method);
result = getImpl(key);
try
{
pool.returnObject(key);
}
catch (Exception e)
{
log.warn(
"Nonfatal error. Could not return key to pool", e);
}
}
catch (Exception e)
{
log.error("", e);
}
}
return result;
}
public Object get(Serializable instanceOrClass, String method,
Serializable arg1)
{
Object result = null;
if (jcsCache != null)
{
try
{
MethodCacheKey key = (MethodCacheKey) pool.borrowObject();
key.init(instanceOrClass, method, arg1);
result = getImpl(key);
try
{
pool.returnObject(key);
}
catch (Exception e)
{
log.warn(
"Nonfatal error. Could not return key to pool", e);
}
}
catch (Exception e)
{
log.error("", e);
}
}
return result;
}
public Object get(Serializable instanceOrClass, String method,
Serializable arg1, Serializable arg2)
{
Object result = null;
if (jcsCache != null)
{
try
{
MethodCacheKey key = (MethodCacheKey) pool.borrowObject();
key.init(instanceOrClass, method, arg1, arg2);
result = getImpl(key);
try
{
pool.returnObject(key);
}
catch (Exception e)
{
log.warn(
"Nonfatal error. Could not return key to pool", e);
}
}
catch (Exception e)
{
log.error("", e);
}
}
return result;
}
public Object get(Serializable instanceOrClass, String method,
Serializable arg1, Serializable arg2,
Serializable arg3)
{
Object result = null;
if (jcsCache != null)
{
try
{
MethodCacheKey key = (MethodCacheKey) pool.borrowObject();
key.init(instanceOrClass, method, arg1, arg2, arg3);
result = getImpl(key);
try
{
pool.returnObject(key);
}
catch (Exception e)
{
log.warn(
"Nonfatal error. Could not return key to pool", e);
}
}
catch (Exception e)
{
log.error("", e);
}
}
return result;
}
public Object get(Serializable[] keys)
{
Object result = null;
if (jcsCache != null)
{
try
{
MethodCacheKey key = (MethodCacheKey) pool.borrowObject();
key.init(keys);
result = getImpl(key);
try
{
pool.returnObject(key);
}
catch (Exception e)
{
log.warn(
"Nonfatal error. Could not return key to pool", e);
}
}
catch (Exception e)
{
log.error("", e);
}
}
return result;
}
public void put(Object value, Serializable instanceOrClass, String method)
{
try
{
MethodCacheKey key = (MethodCacheKey) pool.borrowObject();
key.init(instanceOrClass, method);
putImpl(key, value);
}
catch (Exception e)
{
log.error("", e);
}
}
public void put(Object value, Serializable instanceOrClass,
String method, Serializable arg1)
{
try
{
MethodCacheKey key = (MethodCacheKey) pool.borrowObject();
key.init(instanceOrClass, method, arg1);
putImpl(key, value);
}
catch (Exception e)
{
log.error("", e);
}
}
public void put(Object value, Serializable instanceOrClass, String method,
Serializable arg1, Serializable arg2)
{
try
{
MethodCacheKey key = (MethodCacheKey) pool.borrowObject();
key.init(instanceOrClass, method, arg1, arg2);
putImpl(key, value);
}
catch (Exception e)
{
log.error("", e);
}
}
public void put(Object value, Serializable instanceOrClass, String method,
Serializable arg1, Serializable arg2, Serializable arg3)
{
try
{
MethodCacheKey key = (MethodCacheKey) pool.borrowObject();
key.init(instanceOrClass, method, arg1, arg2, arg3);
putImpl(key, value);
}
catch (Exception e)
{
log.error("", e);
}
}
public void put(Object value, Serializable[] keys)
{
try
{
MethodCacheKey key = (MethodCacheKey) pool.borrowObject();
key.init(keys);
putImpl(key, value);
}
catch (Exception e)
{
log.error("", e);
}
}
public void removeAll(Serializable instanceOrClass, String method)
{
if (jcsCache != null)
{
try
{
MethodCacheKey key = (MethodCacheKey) pool.borrowObject();
key.init(instanceOrClass, method);
String groupName = key.getGroupKey();
jcsCache.invalidateGroup(groupName);
groups.remove(groupName);
try
{
pool.returnObject(key);
}
catch (Exception e)
{
log.warn(
"Nonfatal error. Could not return key to pool", e);
}
}
catch (Exception e)
{
log.error("", e);
}
}
}
public Object remove(Serializable instanceOrClass, String method)
{
Object result = null;
if (jcsCache != null)
{
try
{
MethodCacheKey key = (MethodCacheKey) pool.borrowObject();
key.init(instanceOrClass, method);
result = removeImpl(key);
try
{
pool.returnObject(key);
}
catch (Exception e)
{
log.warn(
"Nonfatal error. Could not return key to pool", e);
}
}
catch (Exception e)
{
log.error("", e);
}
}
return result;
}
public Object remove(Serializable instanceOrClass, String method,
Serializable arg1)
{
Object result = null;
if (jcsCache != null)
{
try
{
MethodCacheKey key = (MethodCacheKey) pool.borrowObject();
key.init(instanceOrClass, method, arg1);
result = removeImpl(key);
try
{
pool.returnObject(key);
}
catch (Exception e)
{
log.warn(
"Nonfatal error. Could not return key to pool", e);
}
}
catch (Exception e)
{
log.error("Error removing element", e);
}
}
return result;
}
public Object remove(Serializable instanceOrClass, String method,
Serializable arg1, Serializable arg2)
{
Object result = null;
if (jcsCache != null)
{
try
{
MethodCacheKey key = (MethodCacheKey) pool.borrowObject();
key.init(instanceOrClass, method, arg1, arg2);
result = removeImpl(key);
try
{
pool.returnObject(key);
}
catch (Exception e)
{
log.warn(
"Nonfatal error: Could not return key to pool", e);
}
}
catch (Exception e)
{
log.error("Error removing element from cache", e);
}
}
return result;
}
public Object remove(Serializable instanceOrClass, String method,
Serializable arg1, Serializable arg2,
Serializable arg3)
{
Object result = null;
if (jcsCache != null)
{
try
{
MethodCacheKey key = (MethodCacheKey) pool.borrowObject();
key.init(instanceOrClass, method, arg1, arg2, arg3);
result = removeImpl(key);
try
{
pool.returnObject(key);
}
catch (Exception e)
{
log.warn(
"Nonfatal error. Could not return key to pool", e);
}
}
catch (Exception e)
{
log.error("Error removing element from cache", e);
}
}
return result;
}
public Object remove(Serializable[] keys)
{
Object result = null;
if (jcsCache != null)
{
try
{
MethodCacheKey key = (MethodCacheKey) pool.borrowObject();
key.init(keys);
result = removeImpl(key);
try
{
pool.returnObject(key);
}
catch (Exception e)
{
log.warn(
"Nonfatal error: Could not return key to pool", e);
}
}
catch (Exception e)
{
log.error("Error removing element from cache", e);
}
}
return result;
}
}