cvs commit: incubator-geronimo/modules/core/src/java/org/apache/geronimo/jmx RelationshipMBeanProxyFactory.java

[da...@apache.org]

dain        2003/08/13 14:21:02

  Added:       modules/core/src/java/org/apache/geronimo/jmx
                        RelationshipMBeanProxyFactory.java
  Log:
  RelationshipMBeanProxyFactory creates a proxies to an mbean based solely on a relationship id and a target role.  The relationship is not resolved until runtime, so the proxy remains valid as the relationship changes over time.
  
  Revision  Changes    Path
  1.1                  incubator-geronimo/modules/core/src/java/org/apache/geronimo/jmx/RelationshipMBeanProxyFactory.java
  
  Index: RelationshipMBeanProxyFactory.java
  ===================================================================
  /* ====================================================================
   * The Apache Software License, Version 1.1
   *
   * Copyright (c) 2003 The Apache Software Foundation.  All rights
   * reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   *
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the
   *    distribution.
   *
   * 3. The end-user documentation included with the redistribution,
   *    if any, must include the following acknowledgment:
   *       "This product includes software developed by the
   *        Apache Software Foundation (http://www.apache.org/)."
   *    Alternately, this acknowledgment may appear in the software itself,
   *    if and wherever such third-party acknowledgments normally appear.
   *
   * 4. The names "Apache" and "Apache Software Foundation" and
   *    "Apache Geronimo" must not be used to endorse or promote products
   *    derived from this software without prior written permission. For
   *    written permission, please contact apache@apache.org.
   *
   * 5. Products derived from this software may not be called "Apache",
   *    "Apache Geronimo", nor may "Apache" appear in their name, without
   *    prior written permission of the Apache Software Foundation.
   *
   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
   * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
   * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
   * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
   * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
   * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   * ====================================================================
   *
   * This software consists of voluntary contributions made by many
   * individuals on behalf of the Apache Software Foundation.  For more
   * information on the Apache Software Foundation, please see
   * <http://www.apache.org/>.
   *
   * ====================================================================
   */
  package org.apache.geronimo.jmx;
  
  import java.lang.reflect.Proxy;
  import java.util.List;
  import javax.management.MBeanServer;
  import javax.management.ObjectName;
  import javax.management.relation.RelationNotFoundException;
  import javax.management.relation.RelationServiceMBean;
  import javax.management.relation.RelationServiceNotRegisteredException;
  import javax.management.relation.RelationTypeNotFoundException;
  import javax.management.relation.RoleInfo;
  import javax.management.relation.RoleInfoNotFoundException;
  import javax.management.relation.RoleNotFoundException;
  
  
  /**
   * RelationshipMBeanProxyFactory creates a dynamic proxy to an MBean based on a relationship end point.
   * The interface type, relationship existience, and object existance is not enforced during construction.
   * Instead, if a method is invoked on the proxy and there is no relationship registered with the specified id
   * or if the target role does not conatin any objects, an InvocationTargetException is thrown, which
   * contains an IllegalStateException.  If an interface method that is not implemented by the MBean is invoked,
   * an InvocationTargetException is thrown, which contains an NoSuchMethodException.
   *
   * @version $Revision: 1.1 $ $Date: 2003/08/13 21:21:02 $
   */
  public final class RelationshipMBeanProxyFactory {
      private RelationshipMBeanProxyFactory() {
      }
  
      /**
       * Creates a dynamic proxy to the specified relationship and targetRole.  The interface of the dynamic proxy
       * id determined by inspecing the RoleInfo of the target role.
       *
       * @param server the mbean server in which the relationship is registered
       * @param relationshipID the id (name) of the relationship
       * @param targetRole the role which contains the object we will be proxying
       * @return a dynamic proxy to the relationship which implements the interface defined by the relationship\
       * @throws IllegalArgumentException if the target role class type is not an interface or if the target
       * roll class could not be loaded
       * @throws IllegalStateException if the relationship does not exist
       */
      public static Object getProxy(MBeanServer server, String relationshipID, String targetRole) {
          RelationServiceMBean relationService = JMXUtil.getRelationService(server);
          Class iface = null;
          try {
              String relationType = relationService.getRelationTypeName(relationshipID);
              RoleInfo roleInfo = relationService.getRoleInfo(relationType, targetRole);
              iface = Thread.currentThread().getContextClassLoader().loadClass(roleInfo.getRefMBeanClassName());
              if (!iface.isInterface()) {
                  throw new IllegalArgumentException("Target Role type is not an interface:" +
                          " relationshipID=" + relationshipID +
                          " targetRole=" + targetRole +
                          " targetRoleClass=" + iface.getName());
              }
          } catch (RelationNotFoundException e) {
              throw new IllegalStateException("MBean relationshipID is not registered: relationshipID=" + relationshipID);
          } catch (RelationTypeNotFoundException e) {
              // this is highly unlikely because we got the relation type from the MBeanServer, but the type could
              // be unregistered between getting it and accessing the role
              throw new IllegalStateException("MBean relationshipID type is not registered: relationshipID=" + relationshipID);
          } catch (RoleInfoNotFoundException e) {
              throw new IllegalStateException("MBean relationshipID does not have target role:" +
                      " relationshipID=" + relationshipID +
                      " target=" + targetRole);
          } catch (ClassNotFoundException e) {
              throw new IllegalArgumentException("Could not load Target Role class:" +
                      " relationshipID=" + relationshipID +
                      " targetRole=" + targetRole +
                      " targetRoleClass=" + iface.getName());
          }
          return getProxy(iface, server, relationshipID, targetRole);
      }
  
      /**
       * Creates a dynamic proxy to the specified relationship and targetRole, which implements the specified
       * interface.
       *
       * @param iface the interface of proxy
       * @param server the mbean server in which the relationship is registered
       * @param relationshipID the id (name) of the relationship
       * @param targetRole the role which contains the object we will be proxying
       * @return a dynamic proxy to the relationship which implements the interface defined by the relationship\
       */
      public static Object getProxy(Class iface, MBeanServer server, String relationshipID, String targetRole) {
          assert (iface != null);
          assert (iface.isInterface());
          assert (server != null);
  
          ClassLoader cl = iface.getClassLoader();
          return Proxy.newProxyInstance(cl, new Class[]{iface}, new LocalHandler(iface, server, relationshipID, targetRole));
      }
  
      private static final class LocalHandler extends AbstractMBeanProxyHandler {
          private final String relationshipID;
          private final String targetRole;
  
          public LocalHandler(Class iface, MBeanServer server, String relationshipID, String targetRole) {
              super(iface, server);
              this.relationshipID = relationshipID;
              this.targetRole = targetRole;
          }
  
          public ObjectName getObjectName() {
              // @todo this should cache the related set and listen for change notifications from relationService
              RelationServiceMBean relationService = JMXUtil.getRelationService(server);
              List relatedMBeans = null;
              try {
                  relatedMBeans = relationService.getRole(relationshipID, targetRole);
              } catch (RelationServiceNotRegisteredException e) {
                  throw new IllegalStateException("MBean relation service is not deployed");
              } catch (RelationNotFoundException e) {
                  throw new IllegalStateException("MBean relationshipID is not registered: relationshipID=" + relationshipID);
              } catch (RoleNotFoundException e) {
                  throw new IllegalStateException("MBean relationshipID does not have target role:" +
                          " relationshipID=" + relationshipID +
                          " target=" + targetRole);
              }
              if (relatedMBeans.size() > 1) {
                  throw new IllegalStateException("MBean is related to more the one MBean");
              }
              if (relatedMBeans.isEmpty()) {
                  throw new IllegalStateException("MBean does not have a realated MBean");
              }
              return (ObjectName) relatedMBeans.iterator().next();
          }
      }
  }