/*
    * Copyright (c) 2004 Peter Antman, Mogul  <peter.antman@mogul.com>
    *
    * $Id: MBeanProxyFactory.java,v 1.2 2004/05/19 12:20:14 pra Exp $
    *
    * This library 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 of the License, or (at your option) any later version
   * 
   * This library 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 library; if not, write to the Free Software
   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   */
  package org.backsource.jmx;
  import java.lang.reflect.Proxy;
  import javax.naming.InitialContext;
  import javax.naming.Context;
  import javax.naming.NamingException;
  import java.lang.reflect.Proxy;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory; 
  
  import javax.management.*;
  
  import org.backsource.utils.naming.NamingHelper;
  /***
   * A factory for creating and binding MBean proxies.
   *
   * <p>This factory will create and bind MBean proxies. These have three capabilities:</p>
   * <ul>
   <li>It makes an MBean types through an interface. The proxy will use the normal JMX invokation style under the hood, but to the caller it is as if invoking a normal object.</li>
   <li>It will bind the proxy in JNDI where it is possible to lookup both locally and remotely. When used locally the invokation will goto directly against the local mbean server, whith one exception - see below, when looked up from a remote JVM (or through a JNDI with remote semantics) the mbean server will be invoked over RMI.</li>
   <li>When configured with jndiURL, the proxy is actually a proxy to another remote MBean server. In that case the invokation will go to the other remote MBean server. Normally one should probably bind these types of proxied in the java: naming domain, since they are reallt meant to be used only locally!</li>
   <p>To be able to guarantee this semantics the rebinds and unbind methods int this class must be used to bind the proxied into JNDI.</p>
   *
   * @author <a href="mailto:pra@mogul.com">Peter Antman</a>
   * @version $Revision: 1.2 $
   */
  
  public class MBeanProxyFactory {
     private static Log log = LogFactory.getLog(MBeanProxyFactory.class);
     /***
      * Create an MBean proxy.
      * @param intf class of interface to cover for.
      * @param name ObjectName of MBean to invoke.
      */
     public static Object create(Class intf, String name)
        throws OperationsException,NamingException
     {
        return Proxy.newProxyInstance(intf.getClassLoader(),
                                      new Class[] { intf },
                                      new MBeanProxy(name));
     }
  
     /***
      * Create an MBean proxy.
      * @param intf class of interface to cover for.
      * @param name ObjectName of MBean to invoke.
      * @param jndiURL a java.naming.provider.url pointing to another JNDI space, which holds an MBean server to invoke, if null the local server is used.
      */
     public static Object create(Class intf, String name, String jndiURL)
        throws OperationsException,NamingException
     {
        return Proxy.newProxyInstance(intf.getClassLoader(),
                                      new Class[] { intf },
                                      new MBeanProxy(name,jndiURL));
     }
  
     /***
      * Create an MBean proxy.
      * @param intf classname of interface to cover for.
      * @param name ObjectName of MBean to invoke.
      * @param jndiURL a java.naming.provider.url pointing to another JNDI space, which holds an MBean server to invoke, if null the local server is used.
      */
  
     public static Object create(String intfName, String name, String jndiURL)
        throws OperationsException,ClassNotFoundException,NamingException
     {
        ClassLoader cl = Thread.currentThread().getContextClassLoader();
        Class intf = cl.loadClass(intfName);
        return create(intf,name,jndiURL);
     }
     
     /***
      * Create an MBean proxy.
      * @param intf classname of interface to cover for.
      * @param name ObjectName of MBean to invoke.
      */
     public static Object create(String intfName, String name)
        throws OperationsException,ClassNotFoundException,NamingException
     {
        ClassLoader cl = Thread.currentThread().getContextClassLoader();
       Class intf = cl.loadClass(intfName);
       return create(intf,name);
    }
 
    /***
     * Helper to bind object at the given jndiName, any missing parent name will
     * be created.
     *
     * <p>by using the method, users will be failsafe if JBoss changes is JNDI semantics. JBoss currently does not serialize object when running in the
 same vm,see org.jnp.interfaces.NamingContext.rebind and lookup and the
 usage of MarshalledValuePair.
  This may ofcource change</p>
     */
    public static void rebind(String jndiName, Object o) throws NamingException {
       try {
          unbind(jndiName);
       } catch (NamingException e) {
          // go a head
       } // end of try-catch
       
 
       NamingHelper.bind(new InitialContext(),
                         jndiName,
                         o
                         );
    }
 
    /***
     * An object bound through the rebind method whould use this method when unbinding!
     */
    public static void unbind(String jndiName) throws NamingException {
       new InitialContext().unbind(jndiName);
    }
    
 }// MBeanProxyFactory