/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.
*/
package org.apache.deltaspike.core.util.context;
import javax.enterprise.context.spi.Contextual;
import javax.enterprise.context.spi.CreationalContext;
import javax.enterprise.inject.spi.BeanManager;
import javax.enterprise.inject.spi.PassivationCapable;
import java.io.Serializable;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
/**
* This Storage holds all information needed for storing
* Contextual Instances in a Context.
*
* It also addresses Serialisation in case of passivating scopes.
*/
public class ContextualStorage implements Serializable
{
private static final long serialVersionUID = 1L;
private final Map<Object, ContextualInstanceInfo<?>> contextualInstances;
private final BeanManager beanManager;
private final boolean concurrent;
private final boolean passivationCapable;
/**
* @param beanManager is needed for serialisation
* @param concurrent whether the ContextualStorage might get accessed concurrently by different threads
* @param passivationCapable whether the storage is for passivation capable Scopes
*/
public ContextualStorage(BeanManager beanManager, boolean concurrent, boolean passivationCapable)
{
this.beanManager = beanManager;
this.concurrent = concurrent;
this.passivationCapable = passivationCapable;
if (concurrent)
{
contextualInstances = new ConcurrentHashMap<Object, ContextualInstanceInfo<?>>();
}
else
{
contextualInstances = new HashMap<Object, ContextualInstanceInfo<?>>();
}
}
/**
* @return the underlying storage map.
*/
public Map<Object, ContextualInstanceInfo<?>> getStorage()
{
return contextualInstances;
}
/**
* @return whether the ContextualStorage might get accessed concurrently by different threads.
*/
public boolean isConcurrent()
{
return concurrent;
}
/**
*
* @param bean
* @param creationalContext
* @param <T>
* @return
*/
public <T> T createContextualInstance(Contextual<T> bean, CreationalContext<T> creationalContext)
{
Object beanKey = getBeanKey(bean);
if (isConcurrent())
{
// locked approach
ContextualInstanceInfo<T> instanceInfo = new ContextualInstanceInfo<T>();
ConcurrentMap<Object, ContextualInstanceInfo<?>> concurrentMap
= (ConcurrentHashMap<Object, ContextualInstanceInfo<?>>) contextualInstances;
ContextualInstanceInfo<T> oldInstanceInfo
= (ContextualInstanceInfo<T>) concurrentMap.putIfAbsent(beanKey, instanceInfo);
if (oldInstanceInfo != null)
{
instanceInfo = oldInstanceInfo;
}
synchronized (instanceInfo)
{
T instance = instanceInfo.getContextualInstance();
if (instance == null)
{
instance = bean.create(creationalContext);
instanceInfo.setContextualInstance(instance);
instanceInfo.setCreationalContext(creationalContext);
}
return instance;
}
}
else
{
// simply create the contextual instance
ContextualInstanceInfo<T> instanceInfo = new ContextualInstanceInfo<T>();
instanceInfo.setCreationalContext(creationalContext);
instanceInfo.setContextualInstance(bean.create(creationalContext));
contextualInstances.put(beanKey, instanceInfo);
return instanceInfo.getContextualInstance();
}
}
/**
* If the context is a passivating scope then we return
* the passivationId of the Bean. Otherwise we use
* the Bean directly.
* @return the key to use in the context map
*/
public <T> Object getBeanKey(Contextual<T> bean)
{
if (passivationCapable)
{
// if the
return ((PassivationCapable) bean).getId();
}
return bean;
}
/**
* Restores the Bean from its beanKey.
* @see #getBeanKey(javax.enterprise.context.spi.Contextual)
*/
public Contextual<?> getBean(Object beanKey)
{
if (passivationCapable)
{
return beanManager.getPassivationCapableBean((String) beanKey);
}
else
{
return (Contextual<?>) beanKey;
}
}
}