/*
* JBoss, Home of Professional Open Source
* Copyright 2006, JBoss Inc., and individual contributors as indicated
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.kernel.spi.lazy;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Set;
import org.jboss.beans.info.spi.BeanInfo;
import org.jboss.kernel.Kernel;
import org.jboss.kernel.spi.config.KernelConfigurator;
/**
* Create lazy proxy of a bean.
*
* @author <a href="mailto:ales.justin@jboss.com">Ales Justin</a>
*/
public class LazyProxyFactory
{
private static volatile LazyInitializer initializer;
private static Map<String, String> initializerMap;
static
{
initializerMap = new LinkedHashMap<String, String>();
// test class name, actual LazyInitializer implementation
initializerMap.put("javassist.util.proxy.ProxyObject", "org.jboss.kernel.plugins.lazy.JavassistLazyInitializer");
initializerMap.put("org.jboss.aop.proxy.container.AOPProxyFactoryParameters", "org.jboss.aop.microcontainer.lazy.JBossAOPLazyInitializer");
initializerMap.put("java.lang.reflect.Proxy", "org.jboss.kernel.plugins.lazy.JDKLazyInitializer");
}
/**
* Get the LazyInitializater instance.
*
* @param configurator the configurator
* @return initializer instance
*/
protected static LazyInitializer getInitializer(KernelConfigurator configurator)
{
if (initializer == null)
{
for(Map.Entry<String, String> entry : initializerMap.entrySet())
{
if (testLibExists(entry.getKey()))
{
initializer = createInitializer(configurator, entry.getValue());
if (initializer != null)
break;
}
}
}
if (initializer == null)
throw new IllegalArgumentException("Cannot initialize LazyInitializater, check classpath for missing classes.");
return initializer;
}
/**
* Check if test class exists.
*
* @param className class name to test
* @return true if test successful, false otherwise
*/
protected static boolean testLibExists(String className)
{
try
{
return Class.forName(className) != null;
}
catch (ClassNotFoundException e)
{
return false;
}
}
/**
* Create initializer instance.
*
* @param configurator the configurator
* @param initializerClassName initializer class name
* @return initializer instance or null if we fail
*/
protected static LazyInitializer createInitializer(KernelConfigurator configurator, String initializerClassName)
{
try
{
BeanInfo beanInfo = configurator.getBeanInfo(initializerClassName, LazyInitializer.class.getClassLoader());
Object result = beanInfo.newInstance();
return LazyInitializer.class.cast(result);
}
catch (Throwable ignored)
{
}
return null;
}
/**
* Create lazy proxy.
*
* @param kernel the kernel
* @param bean the bean to wrap
* @param exposeClass do we expose full class
* @param interfaces interfaces to expose
* @return the proxy
* @throws Throwable for any error
*/
public static Object getProxy(Kernel kernel, String bean, boolean exposeClass, Set<String> interfaces) throws Throwable
{
LazyInitializer lazyInitializer = getInitializer(kernel.getConfigurator());
return lazyInitializer.initializeProxy(kernel, bean, exposeClass, interfaces);
}
}