/*
 * Copyright (c) 2005, 2006, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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 General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */
 

package com.sun.org.glassfish.gmbal ;

import java.lang.reflect.Method ;

import java.security.AccessController;
import java.security.PrivilegedActionException;
import java.security.PrivilegedExceptionAction;
import java.util.logging.Level;
import java.util.logging.Logger;
import com.sun.org.glassfish.gmbal.util.GenericConstructor ;

import javax.management.ObjectName;

/** Factory used to create ManagedObjectManager instances.
 */
public final class ManagedObjectManagerFactory {
    private ManagedObjectManagerFactory() {}
  
    private static GenericConstructor<ManagedObjectManager> objectNameCons =
        new GenericConstructor<ManagedObjectManager>( 
            ManagedObjectManager.class, 
            "com.sun.org.glassfish.gmbal.impl.ManagedObjectManagerImpl",
                ObjectName.class ) ;

    
    private static GenericConstructor<ManagedObjectManager> stringCons =
        new GenericConstructor<ManagedObjectManager>( 
            ManagedObjectManager.class, 
            "com.sun.org.glassfish.gmbal.impl.ManagedObjectManagerImpl",
                String.class ) ;

    /** Convenience method for getting access to a method through reflection.
     * Same as Class.getDeclaredMethod, but only throws RuntimeExceptions.
     * @param cls The class to search for a method.
     * @param name The method name.
     * @param types The array of argument types.
     * @return The Method if found.
     * @throws GmbalException if no such method is found.
     */
    public static Method getMethod( final Class<?> cls, final String name, 
        final Class<?>... types ) {        
        
        try {
            return AccessController.doPrivileged(
                new PrivilegedExceptionAction<Method>() {
                    public Method run() throws Exception {
                        return cls.getDeclaredMethod(name, types);
                    }
                });
        } catch (PrivilegedActionException ex) {
            throw new GmbalException( "Unexpected exception", ex ) ;
        } catch (SecurityException exc) {
            throw new GmbalException( "Unexpected exception", exc ) ;
        }
    }
    
    /** Create a new ManagedObjectManager.  All objectnames created will share
     * the domain value passed on this call.  This ManagedObjectManager is
     * at the top of the containment hierarchy: the parent of the root is null.
     * @param domain The domain to use for all ObjectNames created when
     * MBeans are registered.
     * @return A new ManagedObjectManager.
     */
    public static ManagedObjectManager createStandalone(
        final String domain ) {
	
        ManagedObjectManager result = stringCons.create( domain ) ;
	if (result == null) {
	    return ManagedObjectManagerNOPImpl.self ;
	} else {
	    return result ;
	}
    }
    
    /** Alternative form of the create method to be used when the
     * rootName is not needed explicitly.  If the root name is available
     * from an @ObjectNameKey annotation, it is used; otherwise the
     * type is used as the name, since the root is a singleton.
     * 
     * @param rootParentName The JMX ObjectName of the parent of the root.
     * The parent is outside of the control of this ManagedObjectManager.  
     * The ManagedObjectManager root is a child of the MBean identified
     * by the rootParentName.
     * @return The ManagedObjectManager.
     */
    public static ManagedObjectManager createFederated(
        final ObjectName rootParentName ) {
	
        ManagedObjectManager result = objectNameCons.create( rootParentName ) ;
	if (result == null) {
	    return ManagedObjectManagerNOPImpl.self ;
	} else {
	    return result ;
	}
    }

    /** Return a ManagedObjectManager that performs no operations.  Useful to
     * allow the same code to run with or without creating MBeans through 
     * gmbal.
     * @return ManagedObjectManager that performs no operations.
     */
    public static ManagedObjectManager createNOOP() {
        return ManagedObjectManagerNOPImpl.self ;
    }
}