/*
* JBoss, Home of Professional Open Source
* Copyright 2011, Red Hat, Inc. and/or its affiliates, and individual
* contributors by the @authors tag. See the copyright.txt in the
* distribution for a full listing of individual contributors.
*
* 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.
*/
package org.jboss.seam.persistence;
import java.io.Serializable;
import java.lang.reflect.Method;
import javax.enterprise.inject.Instance;
import javax.enterprise.inject.spi.BeanManager;
import javax.persistence.EntityManager;
import javax.persistence.Query;
import org.jboss.logging.Logger;
import org.jboss.seam.persistence.util.InstanceResolver;
import org.jboss.seam.solder.el.Expressions;
/**
* Proxy handler for a {@link EntityManager} proxy that allows the use of EL in
* queries.
*
* @author Stuart Douglas
*
*/
public class PersistenceContextProxyHandler implements Serializable
{
private static final long serialVersionUID = -6539267789786229774L;
private final EntityManager delegate;
private final Instance<Expressions> expressionsInstance;
static final Logger log = Logger.getLogger(PersistenceContextProxyHandler.class);
public PersistenceContextProxyHandler(EntityManager delegate, BeanManager beanManager)
{
this.delegate = delegate;
expressionsInstance = InstanceResolver.getInstance(Expressions.class, beanManager);
}
public Object invoke(Object proxy, Method method, Object[] args) throws Throwable
{
if ("createQuery".equals(method.getName()) && method.getParameterTypes().length > 0 && method.getParameterTypes()[0].equals(String.class))
{
return handleCreateQueryWithString(method, args);
}
return method.invoke(delegate, args);
}
protected Object handleCreateQueryWithString(Method method, Object[] args) throws Throwable
{
if (args[0] == null)
{
return method.invoke(delegate, args);
}
String ejbql = (String) args[0];
if (ejbql.indexOf('#') > 0)
{
Expressions expressions = expressionsInstance.get();
QueryParser qp = new QueryParser(expressions, ejbql);
Object[] newArgs = args.clone();
newArgs[0] = qp.getEjbql();
Query query = (Query) method.invoke(delegate, newArgs);
for (int i = 0; i < qp.getParameterValues().size(); i++)
{
query.setParameter(QueryParser.getParameterName(i), qp.getParameterValues().get(i));
}
return query;
}
else
{
return method.invoke(delegate, args);
}
}
}