* This file is part of the WfMOpen project.

* Copyright (C) 2001-2003 Danet GmbH (www.danet.de), GS-AN.

* All rights reserved.

*

* This program is free software; you can redistribute it and/or modify

* it under the terms of the GNU General Public License as published by

* the Free Software Foundation; either version 2 of the License, or

* (at your option) any later version.

*

* This program 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 for more details.

*

* You should have received a copy of the GNU General Public License

* along with this program; if not, write to the Free Software

* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

*

* $Id: WorkflowEngineEJB.java 3205 2009-09-27 17:13:47Z mlipp $

*

* $Log$

* Revision 1.29  2007/06/10 05:55:30  drmlipp

* Using local interface for optimization.

*

* Revision 1.28  2007/05/03 21:58:25  mlipp

* Internal refactoring for making better use of local EJBs.

*

*/

* The session bean <code>WorkflowEngineEJB</code> gives access to the

* workflow engine. The remote and home interfaces of this EJB are

* declared in package <code>de.danet.an.workflow.ejbs.util</code> as

* {@link de.danet.an.workflow.ejbs.WorkflowEngine

* <code>WorkflowEngine</code>} and {@link

* de.danet.an.workflow.ejbs.WorkflowEngineHome

* <code>WorkflowEngineHome</code>} because the interfaces are needed

* in all sub-packages and putting the interfaces in a subpackage will

* result in cyclic dependencies. Implementation is in {@link

* de.danet.an.workflow.ejbs.admin this package}, however, because it

* relies on other EJBs from this package. <P>

*

* Setting log level to debug for this class results in progress

* messages during event handling, adds stack traces to warning

* messages and logs the event queue data delivered to clients.

*

* @ejbHome <{de.danet.an.workflow.api.ejbhomes.WorkflowEngineHome}>

* @ejbRemote <{de.danet.an.workflow.ejbs.admin.WorkflowEngine}>

*

* @ejb.bean name="WorkflowEngine" display-name="WorkflowEngine"

* jndi-name="ejb/@@@_JNDI_Name_Prefix_@@@WorkflowEngine"

* type="Stateless" transaction-type="Container" view-type="both"

* @jonas.bean ejb-name="WorkflowEngine"

* jndi-name="ejb/@@@_JNDI_Name_Prefix_@@@WorkflowEngine"

* @ejb.home

* remote-class="de.danet.an.workflow.ejbs.WorkflowEngineHome"

* local-class="de.danet.an.workflow.ejbs.admin.WorkflowEngineLocalHome"

* @ejb.interface remote-class="de.danet.an.workflow.ejbs.WorkflowEngine"

* local-class="de.danet.an.workflow.ejbs.admin.WorkflowEngineLocal"

* extends="javax.ejb.EJBObject, de.danet.an.workflow.spis.rms.ResourceAssignmentContext"

* @ejb.transaction type="Required"

* @ejb.permission role-name="WfMOpenAdmin"

* @ejb.ejb-ref ejb-name="ConfigurationBean" view-type="remote"

* ref-name="ejb/Configuration"

* @ejb.ejb-ref ejb-name="ProcessDefinitionDirectory" view-type="remote"

* @ejb.ejb-ref ejb-name="ProcessDirectory" view-type="remote"

* @ejb.ejb-ref ejb-name="ProcessDirectory" view-type="local"

* @ejb.ejb-ref ejb-name="WorkflowEngine" view-type="remote"

* @ejb.ejb-ref ejb-name="SimpleApplicationDirectory" view-type="local"

* @ejb.ejb-ref ejb-name="SimpleApplicationDirectory" view-type="remote"

* @ejb.ejb-ref ejb-name="TimerHandler" view-type="local"

* ref-name="ejb/TimerHandlerLocal"

* @ejb.ejb-external-ref ref-name="ejb/JdbcKeyGenLocal" link="KeyGen"

* type="Session" view-type="local" home="de.danet.an.util.KeyGenLocalHome"

* business="de.danet.an.util.KeyGenLocal"

* @ejb.resource-ref res-ref-name="jdbc/WfEngine"

* res-type="javax.sql.DataSource" res-auth="Container"

* @jonas.resource res-ref-name="jdbc/WfEngine" jndi-name="jdbc_1"

* @weblogic.enable-call-by-reference True

* @weblogic.resource-description res-ref-name="jdbc/WfEngine"

* jndi-name="DefaultDS"

* @ejb.resource-ref res-ref-name="jms/TCFRemote"

* res-type="javax.jms.TopicConnectionFactory" res-auth="Application"

* @jboss.resource-ref res-ref-name="jms/TCFRemote"

* jndi-name="ConnectionFactory"

* @jonas.resource res-ref-name="jms/TCFRemote" jndi-name="JCF"

* @weblogic.resource-description res-ref-name="jms/TCFRemote"

* jndi-name="weblogic.jms.ConnectionFactory"

* @ejb.resource-ref res-ref-name="jms/TCF"

* res-type="javax.jms.TopicConnectionFactory" res-auth="Container"

* jndi-name="TCF"

* @jboss.resource-ref res-ref-name="jms/TCF" jndi-name="java:/JmsXA"

* @jonas.resource res-ref-name="jms/TCF" jndi-name="TCF"

* @weblogic.resource-description res-ref-name="jms/TCF"

* jndi-name="weblogic.jms.XAConnectionFactory"

* @ejb.resource-ref res-ref-name="jms/QCF"

* res-type="javax.jms.QueueConnectionFactory" res-auth="Container"

* jndi-name="QCF"

* @jboss.resource-ref res-ref-name="jms/QCF" jndi-name="java:/JmsXA"

* @jonas.resource res-ref-name="jms/QCF" jndi-name="QCF"

* @weblogic.resource-description res-ref-name="jms/QCF"

* jndi-name="weblogic.jms.XAConnectionFactory"

* @ejb.resource-ref res-ref-name="jms/InternalEventQueue"

* res-type="javax.jms.Queue" res-auth="Container"

* @jboss.resource-ref res-ref-name="jms/InternalEventQueue"

* jndi-name="queue/@@@_JNDI_Name_Prefix_@@@InternalEventQueue"

* @jonas.resource res-ref-name="jms/InternalEventQueue"

* jndi-name="queue/@@@_JNDI_Name_Prefix_@@@InternalEventQueue"

* @weblogic.resource-description res-ref-name="jms/InternalEventQueue"

* jndi-name="queue/@@@_JNDI_Name_Prefix_@@@InternalEventQueue"

* @ejb.resource-ref res-ref-name="jms/EventService"

* res-type="javax.jms.Topic" res-auth="Container"

* jndi-name="topic/@@@_JNDI_Name_Prefix_@@@EventService"

* @jboss.resource-ref res-ref-name="jms/EventService"

* jndi-name="topic/@@@_JNDI_Name_Prefix_@@@EventService"

* @jonas.resource res-ref-name="jms/EventService"

* jndi-name="topic/@@@_JNDI_Name_Prefix_@@@EventService"

* @weblogic.resource-description res-ref-name="jms/EventService"

* jndi-name="topic/@@@_JNDI_Name_Prefix_@@@EventService"

* @ejb.resource-ref res-ref-name="jms/ChannelIn"

* res-type="javax.jms.Queue" res-auth="Container"

* jndi-name="queue/@@@_JNDI_Name_Prefix_@@@ChannelInMessages"

* @jboss.resource-ref res-ref-name="jms/ChannelIn"

* jndi-name="queue/@@@_JNDI_Name_Prefix_@@@ChannelInMessages"

* @jonas.resource res-ref-name="jms/ChannelIn"

* jndi-name="queue/@@@_JNDI_Name_Prefix_@@@ChannelInMessages"

* @weblogic.resource-description res-ref-name="jms/ChannelIn"

* jndi-name="queue/@@@_JNDI_Name_Prefix_@@@ChannelInMessages"

* @ejb.resource-ref res-ref-name="jms/ChannelOut"

* res-type="javax.jms.Topic" res-auth="Container"

* jndi-name="topic/@@@_JNDI_Name_Prefix_@@@ChannelOutMessages"

* @jboss.resource-ref res-ref-name="jms/ChannelOut"

* jndi-name="topic/@@@_JNDI_Name_Prefix_@@@ChannelOutMessages"

* @jonas.resource res-ref-name="jms/ChannelOut"

* jndi-name="topic/@@@_JNDI_Name_Prefix_@@@ChannelOutMessages"

* @weblogic.resource-description res-ref-name="jms/ChannelOut"

* jndi-name="topic/@@@_JNDI_Name_Prefix_@@@ChannelOutMessages"

* @ejb.env-entry type="java.lang.String"

* name="GlobalConnectionFactoryName" value="null"

* @ejb.env-entry type="java.lang.String"

* name="GlobalQueueConnectionFactoryName" value="null"

* @ejb.env-entry type="java.lang.String"

* name="GlobalTopicConnectionFactoryName" value="null"

* @ejb.env-entry type="java.lang.String" name="GlobalEventTopicName"

* value="topic/@@@_JNDI_Name_Prefix_@@@EventService"

* @ejb.env-entry type="java.lang.String" name="GlobalChannelOutTopicName"

* value="topic/@@@_JNDI_Name_Prefix_@@@ChannelOutMessages"

* @ejb.env-entry type="java.lang.String"

* name="de.danet.an.workflow.assignment.assignmentService"

* value="ejb/@@@_JNDI_Name_Prefix_@@@AssignmentService"

* @weblogic.transaction-isolation TRANSACTION_READ_COMMITTED

*/

    private static final org.apache.commons.logging.Log logger

  = org.apache.commons.logging.LogFactory.getLog

  (WorkflowEngineEJB.class);

    /** Database name */

    private static final String DB_NAME = "java:comp/env/jdbc/WfEngine";

    /** Hibernate session factory savepoint. */

    private static final String HSF_NAME

        = "java:comp/env/hibernate/SessionFactory";

    /** The SessionContext interface of the instance. */

    private SessionContext ctx;

    /**

     * The data source of the database.

     * @see javax.sql.DataSource

     */

    private DataSource ds = null;

    private DBProperties dbProperties = null;

    private SessionFactory hibernateSessionFactoryCache = null;

       

    private TopicConnectionFactory topConFac = null;

    private Topic eventService = null;

    /** Cache for QueueConnectionFactory. */

    private QueueConnectionFactory qcfCache = null;

   

    /** Cache for event queue. */

    private Queue eventQueueCache = null;

   

    /** The cached home interface of the configuration. */

    private ConfigurationHome configurationHomeCache = null;

    /** The cached home interface of the process definition directory. */

    private ProcessDefinitionDirectoryHome processDefinitionDirectoryHomeCache

  = null;

    /** The cached home interface of the process directory. */

    private ProcessDirectoryHome processDirectoryHomeCache = null;

    private ProcessDirectoryLocalHome processDirectoryLocalHomeCache = null;

    /** The resource assignment service. */

    private static boolean rasNotConfigured = false;

    private ResourceAssignmentService rasCache = null;

    /**

     * This operation method delivers a ConfigurationHome

     * interface.

     * @return home interface of the ConfigurationBean

     */

    private ConfigurationHome configurationHome()

  throws ResourceNotAvailableException {

  if (configurationHomeCache == null) {

      configurationHomeCache = (ConfigurationHome)EJBUtil.retrieveEJBHome

    (ConfigurationHome.class, "java:comp/env/ejb/Configuration");

  }

  return configurationHomeCache;

    }

    /**

     * This operation method delivers a ProcessDefinitionDirectoryHome

     * interface.

     * @return home interface of the ProcessDefinitionDirectoryBean

     */

    private ProcessDefinitionDirectoryHome processDefinitionDirectoryHome()

  throws ResourceNotAvailableException {

  if (processDefinitionDirectoryHomeCache == null) {

      processDefinitionDirectoryHomeCache

    = (ProcessDefinitionDirectoryHome)EJBUtil.retrieveEJBHome

    (ProcessDefinitionDirectoryHome.class,

     "java:comp/env/ejb/ProcessDefinitionDirectory");

  }

  return processDefinitionDirectoryHomeCache;

    }

    /**

     * This operation method delivers a ProcessDirectoryHome interface.

     * @return home interface of the ProcessDirectoryBean

     */

    private ProcessDirectoryHome processDirectoryHome()

  throws ResourceNotAvailableException {

  if (processDirectoryHomeCache == null) {

      processDirectoryHomeCache

    = (ProcessDirectoryHome)EJBUtil.retrieveEJBHome

    (ProcessDirectoryHome.class,

     "java:comp/env/ejb/ProcessDirectory");

  }

  return processDirectoryHomeCache;

    }

    /**

     * This operation method delivers a ProcessDirectoryHome interface.

     * @return home interface of the ProcessDirectoryBean

     */

    private ProcessDirectoryLocalHome processDirectoryLocalHome()

  throws ResourceNotAvailableException {

  if (processDirectoryLocalHomeCache == null) {

      processDirectoryLocalHomeCache

    = (ProcessDirectoryLocalHome)EJBUtil.retrieveEJBLocalHome

    (ProcessDirectoryLocalHome.class,

     "java:comp/env/ejb/ProcessDirectoryLocal");

  }

  return processDirectoryLocalHomeCache;

    }

    private QueueConnectionFactory queueConnectionFactory ()

        throws ResourceNotAvailableException {

        if (qcfCache == null) {

            qcfCache = ((QueueConnectionFactory)EJBUtil

                    .retrieveJNDIEntry ("java:comp/env/jms/QCF"));

        }

        return qcfCache;

    }

    private Queue eventQueue ()

        throws ResourceNotAvailableException {

        if (eventQueueCache == null) {

            eventQueueCache = (Queue)EJBUtil.retrieveJNDIEntry

                ("java:comp/env/jms/InternalEventQueue");

        }

        return eventQueueCache;

    }

    /**

     * This method returns the cached resource assignment service.

     * @return the resource assignment service

     */

    private ResourceAssignmentService getRas ()

  throws RemoteException {

  if (rasCache == null && !rasNotConfigured) {

            ResourceAssignmentServiceFactory rasf = null;

      try {

    rasf = ResourceAssignmentServiceFactory.newInstance();

      } catch (de.danet.an.workflow.spis.ras.FactoryConfigurationError

         rae) {

    logger.warn ("No resource assignment service configured. "

                         + "This may be ignored if done intentionally ("

                         + "message from factory: " + rae.getMessage() + ").");

                logger.debug (rae.getMessage(), rae);

    rasNotConfigured = true;

      }

            try {

                rasCache = rasf.newResourceAssignmentService();

            } catch (de.danet.an.workflow.spis.ras.FactoryConfigurationError

                     rae) {

                logger.error ("Problem creating resource assignment service: "

                              + rae.getMessage(), rae);

                rasNotConfigured = true;

            }

  }

  return rasCache;

    }

    /**

     * Set the session context and get new data source. 

     * @param context the given session context.

     * @throws EJBException if problem encountered with getting the data source.

     */

    public void setSessionContext(SessionContext context)

  throws EJBException {

        ctx = context;

  configurationHomeCache = null;

  processDefinitionDirectoryHomeCache = null;

  processDirectoryHomeCache = null;

  processDirectoryLocalHomeCache = null;

  rasCache = null;

  try {

      ds = JDBCUtil.refreshDS(null, DB_NAME);

            dbProperties = JDBCUtil.dbProperties(ds);

      // We should really synchronize on JNDI here, but using the class

      // is very close.

      synchronized (WorkflowEngineEJB.class) {

          try {

                    hibernateSessionFactoryCache

                        = (SessionFactory)EJBUtil.lookupJNDIEntry(HSF_NAME);

                } catch (NamingException e) {

                    logger.debug (HSF_NAME + " not bound, creating...");

                }

                if (hibernateSessionFactoryCache == null) {

                    org.hibernate.cfg.Configuration cfg

                        = new org.hibernate.cfg.Configuration();

                    cfg.setProperty("hibernate.connection.datasource", DB_NAME);

                    cfg.setProperty("hibernate.session_factory_name", HSF_NAME);

                    cfg.addInputStream(WfProcessEJB.class

                            .getResourceAsStream("process.hbm.xml"));

                    hibernateSessionFactoryCache = cfg.buildSessionFactory();

                }

            }

        } catch (NameAlreadyBoundException e) {

            logger.warn("Cannot bind Hibernate session factory (due to "

                        + "concurrency, ignored): " + e.getMessage(), e);

        } catch (SQLException e) {

            throw new EJBException (e);

  } catch (NamingException e) {

      throw new EJBException (e);

  }

    }

   

    /**

     * Create a new instance of ProcessDefinitonDirectoryBean.

     * @throws CreateException Throws if the ProcessDefinitionDirectoryBean

     * can not be created.

     * @ejb.create-method

     * view-type="remote"

     */

    public void ejbCreate() throws CreateException {

  // getting new data source

  try {

      topConFac = (TopicConnectionFactory)

    EJBUtil.lookupJNDIEntry ("java:comp/env/jms/TCF");

      eventService = (Topic)EJBUtil.lookupJNDIEntry

    ("java:comp/env/jms/EventService");

  } catch (NamingException ne) {

      throw new EJBException(ne);

  }

    }

    /**

     * Not called for stateless EJB.

     */

    public void ejbActivate() {

    }

    /**

     * Not called for stateless EJB.

     */

    public void ejbPassivate() {

    }

    /**

     * A container invokes this method before it ends the life of the session

     * object. This happens as a result of a client's invoking a remove

     * operation, or when a container decides to terminate the session object

     * after a timeout.

     * @see javax.ejb.SessionBean

     */

    public void ejbRemove() {

        qcfCache = null;

  configurationHomeCache = null;

  processDefinitionDirectoryHomeCache = null;

  processDirectoryHomeCache = null;

  processDirectoryLocalHomeCache = null;

  rasCache = null;

  ds = null;

    }

    /**

     * Return the instance of the Hibernate session factory.

     *

     * @return the Hibernate session factory

     * @ejb.interface-method view-type="local"

     */

    public SessionFactory hibernateSessionFactory () {

       return hibernateSessionFactoryCache;

    }

   

    //

    // domain methods

    //

    /**

     * Return the workflow engine configuration.

     *

     * @return the configuration.

     * @ejb.interface-method view-type="remote"

     * @ejb.transaction type="Supports"

     */

    public Configuration configuration () {

  try {

      return configurationHome().findByPrimaryKey(new Integer(0));

  } catch (FinderException fe) {

      throw new EJBException (fe);

  } catch (RemoteException re) {

      throw new EJBException (re);

  }

    }

    /**

     * Return the event service connection data. Used by

     * <code>StandardWorkflowService</code> only. This allows to

     * configure the data needed by the client in the server

     * environment and thus eases client configuration.

     *

     * @return the data.

     * @ejb.interface-method view-type="remote"

     * @ejb.transaction type="Supports"

     */

    public Object[] eventServiceData () {

  try {

      String conFacName = (String)EJBUtil.retrieveJNDIEntry

    ("java:comp/env/GlobalConnectionFactoryName");

      String queueConFacName = (String)EJBUtil.retrieveJNDIEntry

    ("java:comp/env/GlobalQueueConnectionFactoryName");

      String topicConFacName = (String)EJBUtil.retrieveJNDIEntry

    ("java:comp/env/GlobalTopicConnectionFactoryName");

      String evtQueueName = (String)EJBUtil.retrieveJNDIEntry

    ("java:comp/env/GlobalEventTopicName");

      String chanOutName = (String)EJBUtil.retrieveJNDIEntry

    ("java:comp/env/GlobalChannelOutTopicName");

      if (logger.isDebugEnabled()) {

    logger.debug

        ("Returning event service data to client: "

         + conFacName + ", " + evtQueueName + ", " + chanOutName);

      }

      return new Object[] { conFacName, queueConFacName, topicConFacName,

          evtQueueName, chanOutName };

  } catch (ResourceNotAvailableException e) {

      throw new EJBException (e);

  }

    }

    /**

     * Return the process definition directory of the workflow engine.

     *

     * @return the process definition directory.

     * @ejb.interface-method view-type="remote"

     * @ejb.transaction type="Supports"

     */

    public de.danet.an.workflow.api.ProcessDefinitionDirectory

  processDefinitionDirectory () {

        RequestScope scope = RequestLog.enterScope

            (this, "processDefinitionDirectory", new Object[] {});

        de.danet.an.workflow.api.ProcessDefinitionDirectory res = null;

        try {

            res = processDefinitionDirectoryHome().create();

  } catch (CreateException ce) {

      throw new EJBException (ce);

  } catch (RemoteException re) {

      throw new EJBException (re);

  } finally {

      scope.leave (res);

  }

  return res;

    }

    /**

     * Return the process directory of the workflow engine.

     *

     * @return the process directory.

     * @ejb.interface-method view-type="remote"

     * @ejb.transaction type="Supports"

     */

    public ExtProcessDirectoryLocal processDirectoryLocal () {

  try {

      return processDirectoryLocalHome().create();

  } catch (CreateException ce) {

      throw new EJBException (ce);

  } catch (RemoteException re) {

      throw new EJBException (re);

  }

    }

    /**

     * Return the process directory of the workflow engine.

     *

     * @return the process directory.

     * @ejb.interface-method view-type="remote"

     * @ejb.transaction type="Supports"

     */

    public ProcessDirectory processDirectory () {

        RequestScope scope = RequestLog.enterScope

            (this, "processDirectory", new Object[] {});

        ProcessDirectory res = null;

  try {

      res = processDirectoryHome().create();

  } catch (CreateException ce) {

      throw new EJBException (ce);

  } catch (RemoteException re) {

      throw new EJBException (re);

  } finally {

      scope.leave (res);

  }

  return res;

    }

    /**

     * Return the resource assignment service used by the

     * workflow engine.

     *

     * @return the resource assignment service

     * @ejb.interface-method view-type="local"

     * @ejb.transaction type="Supports"

     */

    public ResourceAssignmentService resourceAssignmentService () {

        RequestScope scope = RequestLog.enterScope

            (this, "resourceAssignmentService", new Object[] {});

        ResourceAssignmentService res = null;

        try {

            res = getRas ();

        } catch (RemoteException e) {

            throw new EJBException (e);

        } finally {

            scope.leave (res);

        }

        return res;

    }

    /**

     * Return the assignments of a given resource.

     *

     * @param resource the resource.

     * @return the collection of assigned work items (instances of

     * {@link de.danet.an.workflow.omgcore.WfAssignment

     * <code>WfAssignment</code>}).

     * @throws RemoteException if a system-level error occurs.

     * @throws NoSuchResourceException if the resource is invalid.

     * As the environment is a concurrent multi user environment,

     * <code>WfResource</code> objects may become invalid.

     */

    public Collection workItems (WfResource resource)

        throws NoSuchResourceException {

        RequestScope scope = RequestLog.enterScope

            (this, "workItems", new Object[] { resource });

        Collection res = null;

        try {

            res = getRas().workItems(resource);

        } catch (RemoteException e) {

            throw new EJBException (e);

        } finally {

            scope.leave (res);

        }

        return res;

    }

    /**

     * Find out if a given assignment belongs to the work items assigned to

     * a particular resource.

     *

     * @param resource the resource.

     * @param assignment the assignment in question.

     * @return <code>true</code> if the <code>assignment</code> belongs to

     * the work items of the <code>resource</code>.

     * @throws RemoteException if a system-level error occurs.

     * @throws NoSuchResourceException if the resource is invalid.

     * As the environment is a concurrent multi user environment,

     * <code>WfResource</code> objects may become invalid.

     */

    public boolean isMemberOfWorkItems

        (WfResource resource, WfAssignment assignment)

        throws NoSuchResourceException {

        RequestScope scope = RequestLog.enterScope

            (this, "isMemberOfWorkItems",

             new Object[] { resource, assignment });

        boolean res = false;

        try {

            res = getRas().isMemberOfWorkItems(resource, assignment);

        } catch (RemoteException e) {

            throw new EJBException (e);

        } finally {

            scope.leave (new Boolean(res));

        }

        return res;

    }

   

   

    /**

     * Return the known resources.

     *

     * @return the known resources

     * @throws RemoteException if a communication error occurs.

     * @ejb.interface-method view-type="remote"

     * @ejb.transaction type="Supports"

     */

    public Collection knownResources ()

  throws RemoteException {

        RequestScope scope = RequestLog.enterScope

            (this, "knownResources", new Object[] {});

        Collection res = null;

        try {

            ResourceAssignmentService ras = getRas();

            if (ras == null) {

                throw new UnsupportedOperationException

                    ("No resource assignment service configured.");

            }

            res = ras.knownResources ();

        } finally {

            scope.leave (res);

        }

        return res;

    }

    /**

     * Return the resource associated with the given key.

     *

     * @param key the key

     * @return the resource

     * @throws InvalidKeyException if there is no known resource

     * with this key

     * @throws RemoteException if a communication error occurs.

     * @ejb.interface-method view-type="remote"

     * @ejb.transaction type="Supports"

     */

    public WfResource resourceByKey (String key)

  throws InvalidKeyException, RemoteException {

        RequestScope scope = RequestLog.enterScope

            (this, "resourceByKey", new Object[] {});

        WfResource res = null;

        try {

            ResourceAssignmentService ras = getRas();

            if (ras == null) {

                throw new UnsupportedOperationException

                    ("No resource assignment service configured.");

            }

            res = ras.resourceByKey(key);

        } finally {

            scope.leave (res);

        }

        return res;

    }

    /**

     * Return the authorizers for the given resource.

     *

     * @param resource the resource

     * @return the authorizers

     * @throws RemoteException if a communication error occurs.

     * @ejb.interface-method view-type="remote"

     * @ejb.transaction type="Supports"

     */

    public Collection authorizers (WfResource resource)

  throws RemoteException {

        RequestScope scope = RequestLog.enterScope

            (this, "authorizers", new Object[] { resource });

        Collection res = null;

        try {

            ResourceAssignmentService ras = getRas();

            if (ras == null) {

                throw new UnsupportedOperationException

                    ("No resource assignment service configured.");

            }

            res = ras.authorizers(resource);

        } finally {

            scope.leave (res);

        }

        return res;

    }

    /**

     * Return the resource associated with the given principal.

     *

     * @param principal the principal

     * @return the resource

     * @throws RemoteException if a communication error occurs.

     * @throws InvalidKeyException if there is no known resource

     * associated with this principal

     * @ejb.interface-method view-type="remote"

     * @ejb.transaction type="Supports"

     */

    public WfResource asResource (Principal principal)

  throws RemoteException, InvalidKeyException {

        RequestScope scope = RequestLog.enterScope

            (this, "asResource", new Object[] { principal });

        WfResource res = null;

        try {

            ResourceAssignmentService ras = getRas();

            if (ras == null) {

                throw new UnsupportedOperationException

                    ("No resource assignment service configured.");

            }

            res = ras.asResource(principal);

        } finally {

            scope.leave (res);

        }

        return res;

    }

    /**

     * Returns the user currently authenticated as a <code>Principal</code>.

     * @return the caller principal.

     * @ejb.interface-method view-type="remote"

     * @ejb.transaction type="Supports"

     */

    public Principal caller() {

        RequestScope scope = RequestLog.enterScope

            (this, "caller", new Object[] {});

        Principal res = null;

        try {

            res = ctx.getCallerPrincipal();

        } finally {

            scope.leave (res);

        }

        return res;

    }

    /**

     * Terminate a tool in a new transaction, i.e. the transaction

     * attribute of this method is set to <code>RequiresNew</code>.<P>

     *

     * The implementation simply calls

     * <code>appl.terminate(act)</code>.

     *

     * @param appl the application description of the tool

     * @param act the <code>WfActivity</code>

     * @throws ApplicationNotStoppedException if termination is not

     * possible

     * @ejb.interface-method view-type="local"

     * @ejb.transaction type="RequiresNew"

     */

    public void doTerminateLocal (ExtApplication appl, Activity act)

  throws ApplicationNotStoppedException {

  try {

      appl.terminate(act);

  } catch (NoSuchObjectException e) {

      logger.warn

    ("NoSuchObjectException terminating " + appl + " on " + act

     + " (mapped to ApplicationNotStoppedException): "

     + e.getMessage(), e);

      throw new ApplicationNotStoppedException

    (appl + ": " + e.getMessage());

        } catch (RemoteException e) {

            throw new EJBException (e);

  } catch (TransactionRolledbackLocalException e) {

      throw e;

  } catch (RuntimeException e) {

      logger.warn

    ("RuntimeException terminating " + appl + " on " + act

     + "(mapped to ApplicationNotStoppedException): "

     + e.getMessage(), e);

      throw new ApplicationNotStoppedException

    (appl + ": " + e.getMessage());

  }

    }

    /**

     * Returns a collection of <code>WfAuditEvent</code>s associated with

     * this process describing its history.

     * @param execObj the execution object for which to select the audit

     * events

     * @return the collection of audit events

     * @throws HistoryNotAvailableException in case the history is not

     * available for any reason

     * @ejb.interface-method view-type="local"

     * @ejb.transaction type="Supports"

     */

    public Collection history(WfExecutionObject execObj)

  throws HistoryNotAvailableException {

  try {

            return selectAuditEvents(execObj);

  } catch (SQLException sex) {

      throw new EJBException(sex);

  } catch (NamingException nex) {

      logger.error(nex.getMessage(), nex);

      throw new HistoryNotAvailableException();

  } catch (IOException iex) {

      logger.error(iex.getMessage(), iex);

      throw new HistoryNotAvailableException();

  }

    }

    /**

     * Set a result and complete an activity in a new transaction,

     * i.e. the transaction attribute of this method is set to

     * <code>RequiresNew</code>.<P>

     *

     * @param act the <code>WfActivity</code>

     * @param result the tool's result data. If <code>null</code> do

     * not call <code>setResult</code>.

     * @throws InvalidDataException see {@link

     * de.danet.an.workflow.omgcore.WfActivity#setResult

     * <code>WfActivity.setResult(...)</code>}

     * @throws CannotCompleteException see {@link

     * de.danet.an.workflow.omgcore.WfActivity#complete

     * <code>WfActivity.complete()</code>}

     * @ejb.interface-method view-type="remote"

     * @ejb.transaction type="RequiresNew"

     */

    public void doFinish (WfActivity act, Map result)

  throws InvalidDataException, CannotCompleteException {

  try {

      if (act instanceof ActivityProxy) {

          involveContainerInTx((ActivityProxy)act);

          act = ((ActivityProxy)act).unwrap();

      }

      if (result != null) {

    act.setResult (new DefaultProcessData(result));

      }

      act.complete();

  } catch (NoSuchObjectException e) {

      logger.warn

    (act + " does not exist any more "

     + "(mapped to CannotCompleteException): " + e.getMessage());

      logger.debug ("Stacktrace:", e);

      throw new CannotCompleteException (act + ": " + e.getMessage());

  } catch (RemoteException e) {

      throw new EJBException (e);

  } catch (RuntimeException e) {

      logger.warn

    ("RuntimeException while finishing " + act

     + "(mapped to CannotCompleteException): " + e.getMessage());

      logger.debug ("Stacktrace:", e);

      throw new CannotCompleteException (act + ": " + e.getMessage());

  }

    }

    /**

     * Abandon an activity in a new transaction,

     * i.e. the transaction attribute of this method is set to

     * <code>RequiresNew</code>.<P>

     *

     * @param act the <code>WfActivity</code>

     * @param result the exception result to signal

     * @throws TransitionNotAllowedException see {@link

     * de.danet.an.workflow.api.Activity#abandon(String)

     * <code>Activity.abandon()</code>}

     * @ejb.interface-method view-type="remote"

     * @ejb.transaction type="RequiresNew"

     */

    public void doAbandon (Activity act, ExceptionResult result)

  throws TransitionNotAllowedException {

  try {

            if (act instanceof ActivityProxy) {

                involveContainerInTx((ActivityProxy)act);

                act = ((ActivityProxy)act).unwrap();

            }

      ((ExtActivity)act).abandon(result);

  } catch (RemoteException e) {

      throw new EJBException (e);

  }

    }

    /**

     * Register the failure of a tool invocation.<P>

     *

     * @param act the <code>ActivityUniqueKey</code>

     * @ejb.interface-method view-type="remote"

     * @ejb.transaction type="Required"

     */

    public void handleToolInvocationFailed (ActivityUniqueKey act) {

        try {

            QueuerUtils.queue(queueConnectionFactory(), eventQueue(),

                              new ToolInvocationFailedAuditEvent (act));

        } catch (ResourceNotAvailableException e) {

            throw new IllegalStateException (e);

        }

    }

    /**

     * Process the given event. The transaction attribute of this

     * method is set to <code>RequiresNew</code>, so processing will

     * be done in its own transaction.

     * @param event the event.

     * @throws RedeliveryRequiredException if the event should be redelivered

     * @ejb.interface-method view-type="local"

     * @ejb.transaction type="RequiresNew"

     */

    public void processEvent (WfAuditEvent event)

  throws RedeliveryRequiredException {

  if (logger.isDebugEnabled()) {

      logger.debug ("Got audit event: " + event);

  }

  try {

      if (!((DefaultAuditEvent)event).skip ()) {

    feedBack (event);

    // feedback may have caused the rollback already

    // without actually throwing an exception

    if (ctx.getRollbackOnly()) {

        return;

    }

      }

      // now log and publish

      if (!(event instanceof ImplCompleteAuditEvent)

    && !(event instanceof ToolInvocationFailedAuditEvent)) {

    int aes = ((DefaultAuditEvent)event).auditEventSelection ();

    // Note that if we have

    // AUDIT_SELECTION_STATE_EVENTS_ONLY, only state

    // events will be processed here, so we do not have

    // to look at the events again.

    if (aes == ProcessDefinition.AUDIT_SELECTION_ALL_EVENTS

        || aes==ProcessDefinition.AUDIT_SELECTION_STATE_EVENTS_ONLY

        || (aes == (ProcessDefinition

        .AUDIT_SELECTION_PROCESS_CLOSED_EVENTS_ONLY)

      && (event.eventType()

          .equals (WfAuditEvent.PROCESS_STATE_CHANGED))

      && (((WfStateAuditEvent)event)

          .newState().startsWith ("closed")))) {

        if (((DefaultAuditEvent)event).store ()) {

      storeAuditEvent(event);

        }

        publishEvent (event);

    }

      }

  } catch (NoSuchObjectException e) {

      // if any of the objects involved doesn't exist any more,

      // something has gone wrong. But we cannot do anything

      // about it (i.e. shouldn't happen).

      logger.error (event + " discarded: " + e.getMessage(), e);

  } catch (RemoteException e) {

      // we assume that this indicates a temporary condition.

      throw new EJBException (e);

        } catch (EJBException e) {

            // we assume that this indicates a temporary condition.

            throw e;

  } catch (SQLException e) {

      // we assume that this indicates a temporary condition.

      throw new EJBException (e);

  } catch (RedeliveryRequiredException e) {

      // we pass this one

      throw e;

  } catch (Throwable t) {

      // as we are called from a MDB, it makes no sense

      // to pass the exception to caller.

      logger.error (event + " discarded: " + t.getMessage(), t);

      ctx.setRollbackOnly();

  } finally {

      if (logger.isDebugEnabled()) {

    logger.debug ("Event has been processed: " + event);

      }

  }

    }

    /**

     * Queue the given event with a requeued count.

     *

     * @param evt the <code>WfAuditEvent</code>

     * @param requeued the number of times this has been queued

     * @ejb.interface-method view-type="local"

     */

    public void requeueEvent (DefaultAuditEvent evt, int requeued) {

        try {

            QueuerUtils.queue

                (queueConnectionFactory(), eventQueue(), evt, requeued);

        } catch (ResourceNotAvailableException e) {

            throw new EJBException (e);

        }

    }

   

    /**

     * Feed the event back to the engine, i.e. to the processes or activities

     * that may be interested in it.

     * @param event the event.

     * @throws RemoteException if a system-level error occurs.

     * @throws RedeliveryRequiredException if the event should be redelivered

     */

    private void feedBack (WfAuditEvent event)

  throws RemoteException, RedeliveryRequiredException {

  // feed back only those events that we know the receivers to

  // be interested in

  boolean processHandles = AbstractProcess.isHandled (event);

  boolean activityHandles = (event.activityKey() != null

           && AbstractActivity.isHandled (event));

  if (!(processHandles || activityHandles)) {

      if (logger.isDebugEnabled()) {

    logger.debug ("Not feeding back " + event);

      }

      return;

  }

  ExtProcessDirectoryLocal procDir = null;

  try {

      // Source is not usable internally (remote object). Lookup

            // local object in order to get process and (maybe) activity

            // in transaction.

      procDir = processDirectoryLocal();

      ProcessLocal proc = procDir.lookupProcessLocal

    (event.processMgrName(), event.processKey());

            ExtActivityLocal actLocal = null;

      if (event.activityKey() != null) {

                actLocal = (ExtActivityLocal)

                    proc.activityByKeyLocal (event.activityKey());

      }

      if (activityHandles) {

    actLocal.handleAuditEvent (event);

      }

      if (processHandles) {

    ((ExtProcessLocal)proc).handleAuditEvent (event);

      }

      if (logger.isDebugEnabled()) {

    logger.debug ("Fed back event: " + event);

      }

  } catch (InvalidKeyException e) {

      // There is a race condition between creation of the

      // process and starting it. If both create and start are

      // performed within the same transaction, it may happen

      // that the event generated by the call to start becomes

      // visible before the process, i.e. the data in the

      // database. In this case, the thread processing the event

      // may not find the process.

      if (event instanceof WfStateAuditEvent

    && event.eventType().equals (WfAuditEvent.PROCESS_STATE_CHANGED)

    && (((WfStateAuditEvent)event).newState()

        .equals (RunningState.RUNNING.toString ()))) {

    throw new RedeliveryRequiredException

        ("Process not found (yet) for " + event);

      }

      // Else if we cannot lookup the process, well then this event

      // is no good.

      logger.warn (event + " discarded, process no longer available.");

  } finally {

      EJBUtil.removeSession(procDir);

  }

    }

    /**

     * Feed the event back to the engine, i.e. to the processes or activities

     * that may be interested in it.

     * @param event the event.

     * @throws RemoteException if a system-level error occurs.

     */

    private void publishEvent (WfAuditEvent event)

  throws RemoteException {

  ProcessDirectory procDir = null;

  TopicConnection evtSvcCon = null;

  TopicSession evtSvcSession = null;

  try {

      evtSvcCon = topConFac.createTopicConnection();

      evtSvcSession = evtSvcCon.createTopicSession (true, 0);

      TopicPublisher evtSvcPublisher

                = evtSvcSession.createPublisher (eventService);

      evtSvcPublisher.setDisableMessageID (true);

      ObjectMessage msg = evtSvcSession.createObjectMessage();

      msg.setStringProperty ("processKey", event.processKey());

      msg.setStringProperty ("eventType", event.eventType());

      msg.setObject ((Serializable)event);

      evtSvcPublisher.publish (msg);

      if (logger.isDebugEnabled ()) {

    logger.debug ("Published event " + event);

      }

      evtSvcPublisher.close ();

  } catch (JMSException e) {

      logger.error ("Cannot publish "+event+": "+e.getMessage (), e);

  } finally {

      EJBUtil.removeSession(procDir);

      QueuerUtils.release(evtSvcCon, evtSvcSession);

  }

    }

    //

    // Helper methods

    //

    /**

     * Stores the given audit event data to the database.

     * @param event the event.

     * @throws SQLException in case of database access problems

     * @throws IOException in case of i/o problems

     */

    private void storeAuditEvent(WfAuditEvent event)

  throws SQLException, IOException {

  Connection con = null;

  UniversalPrepStmt prepStmt = null;

  try {

      con = ds.getConnection();

      // prepare statement

      prepStmt = new UniversalPrepStmt

    (ds, con, "INSERT INTO AuditEvents "

    + " (DBId, EventTime, EventType, ActivityKey,"

    + " ActivityName, ProcessKey, ProcessName, ProcessMgrName,"

    + " ProcessMgrVersion, EventData1, EventData2,"

    + " EventData3, EventData4, EventData5)"

    + " VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)");

      // primary key

      long primKey = EJBUtil.newPrimaryKey("AuditEvents");

      int offset = 1;

      prepStmt.setLong(offset++, primKey);

     

      // misc. data

      setupAuditEventInsertData (event, prepStmt, offset, primKey);

     

      // execute insert statement

      int rowCount = prepStmt.executeUpdate();

      if (rowCount == 0) {

    throw new EJBException

        ("Inserting audit event >>> " + event + " <<< failed.");

      }

     

      // data audit events are stored in different tables

      if (event instanceof WfDataAuditEvent){

    WfDataAuditEvent ev = (WfDataAuditEvent)event;

    storeDataAuditEventProcessData

        (con, primKey, ev.oldData(), ev.newData());

      }

      if (logger.isDebugEnabled ()) {

    logger.debug ("Saved event " + event);

      }

  } catch (ResourceNotAvailableException e) {

      throw new SQLException ("Cannot get primary key" + e.getMessage());

  } finally {

      JDBCUtil.closeAll (null, prepStmt, con);

  }

    }

   

    /**

     * Sets up the entire data fields of the given prepared statement with

     * values of the given event.

     * @param event the data source event

     * @param prepStmt the insert statement

     * @param offset an offset of the statement's parameter list

     * @param mapId an identifier for a persistant map (in use for data audit

     * events, only.)

     * @throws SQLException in case of database access problems

     * @throws IOException in case of other i/o problems

     */

    private void setupAuditEventInsertData

  (WfAuditEvent event, UniversalPrepStmt prepStmt, int offset,

   long recKey)

  throws SQLException, IOException {

 

  // data common to all events

  prepStmt.setTimestamp (offset++,

             new Timestamp(event.timeStamp().getTime()));

  prepStmt.setString (offset++, event.eventType());

  prepStmt.setString (offset++, event.activityKey());

  prepStmt.setString (offset++, event.activityName());

  prepStmt.setString (offset++, event.processKey());

  prepStmt.setString (offset++, event.processName());

  prepStmt.setString (offset++, event.processMgrName());

  prepStmt.setString (offset++, event.processMgrVersion());

     

  // event specific data

  String eventData1 = null;

  String eventData2 = null;

  String eventData3 = null;

  String eventData4 = null;

  String eventData5 = null;

  if (event instanceof WfAssignmentAuditEvent){

      WfAssignmentAuditEvent ev = (WfAssignmentAuditEvent)event;

      eventData1 = ev.oldResourceKey();

      eventData2 = ev.oldResourceName();

      eventData3 = ev.newResourceKey();

      eventData4 = ev.newResourceName();

  } else if (event instanceof WfCreateProcessAuditEvent){

      WfCreateProcessAuditEvent ev = (WfCreateProcessAuditEvent)event;

      eventData1 = ev.pActivityKey();

      eventData2 = ev.pProcessKey();

      eventData3 = ev.pProcessName();

      eventData4 = ev.pProcessMgrName();

      eventData5 = ev.pProcessMgrVersion();

  } else if (event instanceof WfDataAuditEvent){

      eventData1 = Long.toString (recKey);

  } else if (event instanceof WfStateAuditEvent){

      WfStateAuditEvent ev = (WfStateAuditEvent)event;

      eventData1 = ev.oldState();

      eventData2 = ev.newState();

  }

  prepStmt.setString (offset++, eventData1);

  prepStmt.setString (offset++, eventData2);

  prepStmt.setString (offset++, eventData3);

        prepStmt.setString (offset++, eventData4);

  prepStmt.setString (offset++, eventData5);

    }

    /**

     * Stores process data associated to a data audit event as identifed

     * by the given map id.

     * @param con the database connection to use

     * @param mapId the primary key that identifies the assocaited data

     * audit event

     * @param oldData the old data

     * @param newData the new data

     * @throws IOException in case of io problems

     */

    private void storeDataAuditEventProcessData

  (Connection con, long recKey, Map oldData, Map newData)

  throws SQLException, IOException {

  JDBCPersistentMap m = null;

  try {

      Long key = new Long(recKey);

      // old data

      if (oldData != null){

    m = new JDBCPersistentMap (ds, key, "DataAuditEventOldData");

    m.setConnection(con);

    m.setMapId (key);

    m.setNewMap ();

    m.putAll(oldData);

    try {

        m.store();

    } catch (PersistentMapSQLException e) {

        throw (SQLException)e.getCause();

    }

    m.setConnection(null);

      }

     

      // new data

      if (newData != null){

    m = new JDBCPersistentMap (ds, key, "DataAuditEventNewData");

    m.setConnection(con);

    m.setMapId (key);

    m.setNewMap ();

    m.putAll(newData);

    try {

        m.store();

    } catch (PersistentMapSQLException e) {

        throw (SQLException)e.getCause();

    }

    m.setConnection(null);

      }

  } finally {

      m.setConnection(null);

  }

    }

    /**

     * Returns a collection of <code>WfAuditEvent</code>s associated with

     * this process and stored in the database.

     * @param execObj the execution object for which to select the audit

     * events

     * @return the collection of audit events

     */

    private Collection selectAuditEvents(WfExecutionObject execObj)

  throws SQLException, IOException, NamingException {

  Connection con = null;

  PreparedStatement prepStmt = null;

  ResultSet rs = null;

  try {

      Collection events = new ArrayList();

      con = ds.getConnection();

            String selectStatement = "SELECT * FROM auditevents ";

            if (execObj instanceof WfProcess){

    selectStatement

        += " WHERE ProcessKey = ? AND ActivityKey IS NULL";