geronimo-scm mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From d...@apache.org
Subject cvs commit: incubator-geronimo/modules/kernel/src/java/org/apache/geronimo/kernel/service DependencyService2.java
Date Thu, 06 Nov 2003 19:50:08 GMT
dain        2003/11/06 11:50:08

  Added:       modules/kernel/src/java/org/apache/geronimo/kernel/service
                        DependencyService2.java
  Log:
  New simplified dependency service.  This should be moved to
  DependencyService.java when the rest of the mbeans are updated.
  
  Revision  Changes    Path
  1.1                  incubator-geronimo/modules/kernel/src/java/org/apache/geronimo/kernel/service/DependencyService2.java
  
  Index: DependencyService2.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.kernel.service;
  
  import java.util.Collection;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.Iterator;
  import java.util.LinkedList;
  import java.util.List;
  import java.util.Map;
  import java.util.Set;
  import javax.management.JMException;
  import javax.management.MBeanRegistration;
  import javax.management.MBeanServer;
  import javax.management.MBeanServerNotification;
  import javax.management.Notification;
  import javax.management.NotificationFilterSupport;
  import javax.management.NotificationListener;
  import javax.management.ObjectName;
  
  import org.apache.geronimo.kernel.jmx.JMXUtil;
  
  /**
   * DependencyService is the record keeper of the dependencies in Geronimo.  The DependencyService
   * does not enforce any dependencies, it is simply a place where components can register
thier intent
   * to be dependent on another component.  Since a JMX Component can pretty much do whatever
it wants
   * a component must watch the components it depends on to assure that they are following
the
   * J2EE-Management state machine.
   *
   * The DependencyService uses the nomenclature of parent-child where a child is dependent
on a parent.
   * The names parent and child have no other meaning are just a convience to make the code
readable.
   *
   * @jmx:mbean
   *
   * @version $Revision: 1.1 $ $Date: 2003/11/06 19:50:08 $
   */
  public class DependencyService2 implements MBeanRegistration, NotificationListener, DependencyService2MBean
{
      /**
       * The mbean server we are registered with.
       */
      private MBeanServer server;
  
      /**
       * A map from child names to a list of parents.
       */
      private final Map childToParentMap = new HashMap();
  
      /**
       * A map from parent back to a list of its children.
       */
      private final Map parentToChildMap = new HashMap();
  
      /**
       * A map from a component's ObjectName to the list of ObjectPatterns that the component
is blocking
       * from starting.
       */
      private final Map startHoldsMap = new HashMap();
  
      public ObjectName preRegister(MBeanServer server, ObjectName objectName) throws Exception
{
          if (objectName == null) {
              objectName = JMXUtil.DEPENDENCY_SERVICE_NAME;
          }
          this.server = server;
  
          NotificationFilterSupport mbeanServerFilter = new NotificationFilterSupport();
          mbeanServerFilter.enableType(MBeanServerNotification.UNREGISTRATION_NOTIFICATION);
          server.addNotificationListener(JMXUtil.DELEGATE_NAME, this, mbeanServerFilter, null);
  
          return objectName;
      }
  
      public void postRegister(Boolean aBoolean) {
      }
  
      public void preDeregister() throws Exception {
      }
  
      public void postDeregister() {
          try {
              server.removeNotificationListener(JMXUtil.DELEGATE_NAME, this);
          } catch (JMException ignored) {
              // no big deal... just good citizen clean up code
          }
          synchronized(this) {
              server = null;
              childToParentMap.clear();
              parentToChildMap.clear();
              startHoldsMap.clear();
          }
      }
  
      /**
       * Declares a dependency from a child to a parent.
       * @param child the dependent component
       * @param parent the component the child is depending on
       *
       * @jmx:managed-operation
       */
      public synchronized void addDependency(ObjectName child, ObjectName parent) {
          Set parents = (Set) childToParentMap.get(child);
          if (parents == null) {
              parents = new HashSet();
              childToParentMap.put(child, parents);
          }
          parents.add(parent);
  
          Set children = (Set) parentToChildMap.get(parent);
          if (children == null) {
              children = new HashSet();
              parentToChildMap.put(parent, children);
          }
          children.add(child);
      }
  
      /**
       * Removes a dependency from a child to a parent
       * @param child the dependnet component
       * @param parent the component that the child wil no longer depend on
       *
       * @jmx:managed-operation
       */
      public synchronized void removeDependency(ObjectName child, ObjectName parent) {
          Set parents = (Set) childToParentMap.get(child);
          if (parents != null) {
              parents.remove(parent);
          }
  
          Set children = (Set) parentToChildMap.get(parent);
          if (children != null) {
              children.remove(child);
          }
      }
  
      /**
       * Removes all dependencies for a child
       * @param child the component that will no longer depend on anything
       *
       * @jmx:managed-operation
       */
      public synchronized void removeAllDependencies(ObjectName child) {
          Set parents = (Set) childToParentMap.remove(child);
          if(parents == null) {
              return;
          }
          for (Iterator iterator = parents.iterator(); iterator.hasNext();) {
              ObjectName parent = (ObjectName) iterator.next();
              Set children = (Set) parentToChildMap.get(parent);
              if (children != null) {
                  children.remove(child);
              }
  
          }
      }
  
      /**
       * Adds dependcies from the child to every parent in the parents set
       * @param child the dependent component
       * @param parents the set of components the child is depending on
       *
       * @jmx:managed-operation
       */
      public synchronized void addDependencies(ObjectName child, Set parents) {
          Set existingParents = (Set) childToParentMap.get(child);
          if (existingParents == null) {
              existingParents = new HashSet(parents);
              childToParentMap.put(child, existingParents);
          } else {
              existingParents.addAll(parents);
          }
  
          for (Iterator i = parents.iterator(); i.hasNext();) {
              Object startParent = i.next();
              Set children = (Set) parentToChildMap.get(startParent);
              if (children == null) {
                  children = new HashSet();
                  parentToChildMap.put(startParent, children);
              }
              children.add(child);
          }
      }
  
      /**
       * Gets the set of parents that the child is depending on
       * @param child the depend component
       * @return a collection containing all of the components the child depends on; will
never be null
       *
       * @jmx:managed-operation
       */
      public synchronized Set getParents(ObjectName child) {
          Set parents = (Set) childToParentMap.get(child);
          if (parents == null) {
              return Collections.EMPTY_SET;
          }
          return parents;
      }
  
      /**
       * Gets all of the MBeans that have a dependency on the specificed startParent.
       * @param parent the component the returned childen set depend on
       * @return a collection containing all of the components that depend on the parent;
will never be null
       *
       * @jmx:managed-operation
       */
      public synchronized Set getChildren(ObjectName parent) {
          Set children = (Set) parentToChildMap.get(parent);
          if (children == null) {
              return Collections.EMPTY_SET;
          }
          return children;
      }
  
      /**
       * Adds a hold on a collection of object name patterns.  If the name of a component
matches an object name
       * pattern in the collection, the component should not start.
       * @param objectName the name of the component placing the holds
       * @param holds a collection of object name patterns which should not start
       *
       * @jmx:managed-operation
       */
      public synchronized void addStartHolds(ObjectName objectName, Collection holds) {
          Collection currentHolds = (Collection)startHoldsMap.get(objectName);
          if(currentHolds == null) {
              currentHolds = new LinkedList(holds);
              startHoldsMap.put(objectName, currentHolds);
          } else {
              currentHolds.addAll(holds);
          }
      }
  
      /**
       * Removes a collection of holds.
       * @param objectName the object name of the components owning the holds
       * @param holds a collection of the holds to remove
       *
       * @jmx:managed-operation
       */
      public synchronized void removeStartHolds(ObjectName objectName, Collection holds) {
          Collection currentHolds = (Collection)startHoldsMap.get(objectName);
          if(currentHolds != null) {
              currentHolds.removeAll(holds);
          }
      }
  
      /**
       * Removes all of the holds owned by a component.
       * @param objectName the object name of the component that will no longer have any holds
       *
       * @jmx:managed-operation
       */
      public synchronized void removeAllStartHolds(ObjectName objectName) {
          startHoldsMap.remove(objectName);
      }
  
      /**
       * Gets the object name of the mbean blocking the start specified mbean.
       * @param objectName the mbean to check for blockers
       * @return the mbean blocking the specified mbean, or null if there are no blockers
       *
       * @jmx:managed-operation
       */
      public synchronized ObjectName checkBlocker(ObjectName objectName) {
          // check if objectName name is on one of the hold lists
          for (Iterator iterator = startHoldsMap.keySet().iterator(); iterator.hasNext();)
{
              ObjectName blocker = (ObjectName) iterator.next();
              List holds = (List) startHoldsMap.get(blocker);
              for (Iterator holdsIterator = holds.iterator(); holdsIterator.hasNext();) {
                  ObjectName pattern = (ObjectName) holdsIterator.next();
                  if(pattern.apply(objectName)) {
                      return blocker;
                  }
              }
          }
          return null;
      }
  
      public void handleNotification(Notification n, Object handback) {
          String type = n.getType();
          if (MBeanServerNotification.UNREGISTRATION_NOTIFICATION.equals(type)) {
              MBeanServerNotification notification = (MBeanServerNotification) n;
              ObjectName source = notification.getMBeanName();
              synchronized(this) {
                  removeAllDependencies(source);
                  removeAllStartHolds(source);
              }
          }
      }
  }
  
  
  

Mime
View raw message