001    /*****************************************************************************
002     * Copyright (C) NanoContainer Organization. All rights reserved.            *
003     * ------------------------------------------------------------------------- *
004     * The software in this package is published under the terms of the BSD      *
005     * style license a copy of which has been included with this distribution in *
006     * the LICENSE.txt file.                                                     *
007     *                                                                           *
008     * Original code by Joerg Schaible                                           *
009     *****************************************************************************/
010    
011    package org.picocontainer.gems.jmx;
012    
013    import javax.management.DynamicMBean;
014    import javax.management.MalformedObjectNameException;
015    import javax.management.ObjectName;
016    
017    import org.picocontainer.ComponentAdapter;
018    import org.picocontainer.PicoContainer;
019    
020    
021    /**
022     * DynamicMBeanProvider, that will provide a component directly if it is already a {@link DynamicMBean}.
023     * @author Jörg Schaible
024     */
025    public class DynamicMBeanComponentProvider implements DynamicMBeanProvider {
026    
027        private final ObjectNameFactory objectNameFactory;
028    
029        /**
030         * Construct a DynamicMBeanComponentProvider. This instance will use a {@link TypedObjectNameFactory} and register
031         * all MBeans in the default domain of the {@link javax.management.MBeanServer}.
032         */
033        public DynamicMBeanComponentProvider() {
034            this(new TypedObjectNameFactory());
035        }
036    
037        /**
038         * Construct a DynamicMBeanComponentProvider with a specified ObjectNameFactory.
039         * @param factory The {@link ObjectNameFactory}.
040         */
041        public DynamicMBeanComponentProvider(final ObjectNameFactory factory) {
042            if (factory == null) {
043                throw new NullPointerException("ObjectFactoryName is null");
044            }
045            objectNameFactory = factory;
046        }
047    
048        /**
049         * Provide the component itself as {@link DynamicMBean} if it is one and if an {@link ObjectName} can be created.
050         * @see org.picocontainer.gems.jmx.DynamicMBeanProvider#provide(org.picocontainer.PicoContainer,
051         *      org.picocontainer.ComponentAdapter)
052         */
053        public JMXRegistrationInfo provide(final PicoContainer picoContainer, final ComponentAdapter componentAdapter) {
054            if (DynamicMBean.class.isAssignableFrom(componentAdapter.getComponentImplementation())) {
055                final DynamicMBean mBean = (DynamicMBean)componentAdapter.getComponentInstance(picoContainer,null);
056                try {
057                    final ObjectName objectName = objectNameFactory.create(componentAdapter.getComponentKey(), mBean);
058                    if (objectName != null) {
059                        return new JMXRegistrationInfo(objectName, mBean);
060                    }
061                } catch (final MalformedObjectNameException e) {
062                    throw new JMXRegistrationException("Cannot create ObjectName for component '"
063                            + componentAdapter.getComponentKey()
064                            + "'", e);
065                }
066            }
067            return null;
068        }
069    }