Commons Modeler example source code file (RegistryMBean.java)

This example Commons Modeler source code file (RegistryMBean.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Commons Modeler tags/keywords

classloader, exception, exception, list, list, object, object, registrymbean, string, string, util

The Commons Modeler RegistryMBean.java source code

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.apache.commons.modeler;


import java.util.List;

/**
 * Interface for modeler MBeans.
 * 
 * This is the main entry point into modeler. It provides methods to create
 * and manipulate model mbeans and simplify their use.
 *
 * Starting with version 1.1, this is no longer a singleton and the static
 * methods are strongly deprecated. In a container environment we can expect
 * different applications to use different registries.
 * 
 * @author Craig R. McClanahan
 * @author Costin Manolache
 * 
 * @since 1.1
 */
public interface RegistryMBean {

    /** 
     * Load an extended mlet file. The source can be an URL, File or
     * InputStream. 
     * 
     * All mbeans will be instantiated, registered and the attributes will be 
     * set. The result is a list of ObjectNames.
     *
     * @param source InputStream or URL of the file
     * @param cl ClassLoader to be used to load the mbeans, or null to use the
     *        default JMX mechanism ( i.e. all registered loaders )
     * @return List of ObjectName for the loaded mbeans
     * @throws Exception
     * 
     * @since 1.1
     */ 
    public List loadMBeans( Object source, ClassLoader cl ) throws Exception;

    /** Invoke an operation on a set of mbeans. 
     * 
     * @param mbeans List of ObjectNames
     * @param operation Operation to perform. Typically "init" "start" "stop" or "destroy"
     * @param failFirst Behavior in case of exceptions - if false we'll ignore
     *      errors
     * @throws Exception
     */ 
    public void invoke( List mbeans, String operation, boolean failFirst )
            throws Exception;

    /** Register a bean by creating a modeler mbean and adding it to the 
     * MBeanServer.
     * 
     * If metadata is not loaded, we'll look up and read a file named
     * "mbeans-descriptors.ser" or "mbeans-descriptors.xml" in the same package
     * or parent.
     *
     * If the bean is an instance of DynamicMBean. it's metadata will be converted
     * to a model mbean and we'll wrap it - so modeler services will be supported
     *
     * If the metadata is still not found, introspection will be used to extract
     * it automatically. 
     * 
     * If an mbean is already registered under this name, it'll be first
     * unregistered.
     * 
     * If the component implements MBeanRegistration, the methods will be called.
     * If the method has a method "setRegistry" that takes a RegistryMBean as
     * parameter, it'll be called with the current registry.
     * 
     *
     * @param bean Object to be registered
     * @param oname Name used for registration
     * @param type The type of the mbean, as declared in mbeans-descriptors. If
     * null, the name of the class will be used. This can be used as a hint or
     * by subclasses.
     *
     * @since 1.1
     */ 
    public void registerComponent(Object bean, String oname, String type)
           throws Exception;

    /** Unregister a component. We'll first check if it is registered,
     * and mask all errors. This is mostly a helper.
     * 
     * @param oname
     * 
     * @since 1.1
     */ 
    public void unregisterComponent( String oname );


     /** Return an int ID for faster access. Will be used for notifications
      * and for other operations we want to optimize. 
      *
      * @param domain Namespace 
      * @param name  Type of the notification
      * @return  An unique id for the domain:name combination
      * @since 1.1
      */
    public int getId( String domain, String name);


    /** Reset all metadata cached by this registry. Should be called 
     * to support reloading. Existing mbeans will not be affected or modified.
     * 
     * It will be called automatically if the Registry is unregistered.
     * @since 1.1
     */ 
    public void stop();

    /** Load descriptors. The source can be a File, URL pointing to an
     * mbeans-descriptors.xml.
     * 
     * Also ( experimental for now ) a ClassLoader - in which case META-INF/ will
     * be used.
     * 
     * @param source
     */ 
    public void loadMetadata(Object source ) throws Exception;
}