3 Replies Latest reply on Apr 5, 2006 10:03 AM by gavin.king

    BPM Variable Injection

    go_rags
    go_rags Apr 4, 2006 6:23 PM

      I have put together a sample BPM demo using seam. I am having some trouble with accessing the variables. I have 2 BPM flows both use the same action handler.

      Flow 1 : start -> assign to actor -> call event (actionhandler) -> end
      Flow 2 : start -> call event (action handler) -> assign to actor -> end

      I inject 2 process context variables at the time of the process creation.

      In the first case my stuff is working fine. But in the second case I am not able to access the variables I injected, when I retrive them in the action handler I am getting a NULL value.

      Flow 1 :
      ~~~~~


      <process-definition name="nbook">

 <start-state name="start">
 <transition to="review"/>
 </start-state>

 <task-node name="nreview">
 <task name="nreview">
 <assignment actor-id="#{userId}"/>
 </task>
 <transition to="done"/>
 </task-node>

 <task-node name="assigncell">
 <event type="node-enter">
 <action name="assigncell" class="com.rags.action.AssignCell"></action>
 </event>
 <transition to="done"></transition>
 </task-node>

 <end-state name="done"/>

</process-definition>


      Flow 2 :
      ~~~~~ 

      <process-definition name="bbook">

 <start-state name="start">
 <transition to="assigncell"/>
 </start-state>

 <task-node name="assigncell">
 <event type="node-enter">
 <action name="assigncell" class="com.rags.action.AssignCell"></action>
 </event>
 <transition to="breview"></transition>
 </task-node>


 <task-node name="breview">
 <task name="breview">
 <assignment actor-id="#{user.username}"/>
 </task>
 <transition to="done"/>
 </task-node>

 <end-state name="done"/>

</process-definition>

      Action Handler :
      ~~~~~~~~~~~ 
      package com.rags.action;

import org.jbpm.graph.def.ActionHandler;
import org.jbpm.graph.exe.ExecutionContext;

public class AssignCell implements ActionHandler {

 public void execute(ExecutionContext bpmContext) throws Exception {



 String bookName = (String)bpmContext.getVariable("bookName");

 String bookStatus = (String)bpmContext.getVariable("bookStatus");

 int cell = Math.abs(bookName.hashCode() % 35);
 char block = (char)(Math.abs(bookName.hashCode() % 26) + 65);

 bookStatus = "Assigned to Block : " + block + " Cell : " + cell;

 bpmContext.setVariable("bookStatus", bookStatus);

 }

}


      Can somebody tell me where I am going wrong?

      Thanks,
      Raghu.




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        • 1. Re: BPM Variable Injection
          gavin.king
          gavin.king Apr 4, 2006 6:29 PM (in response to go_rags)

          Why not use a Seam component instead of a jBPM ActionHandler, and use @Out(scope=BUSINESS_PROCESS)?

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          • 2. Re: BPM Variable Injection
            go_rags
            go_rags Apr 5, 2006 9:59 AM (in response to go_rags)

            Gavin,

            The intent is to prove that a jBPM (action or a webservice call) can also be performed as part of the demo. So I have to use the ActionHandler and a Webservice to complete the demo.


            At the risk of sidetracking the issue, I faced a problem while i replaced the action handler with a seam component and I got an exception. Obviously I am doing something wrong because the numberguess example works fine. Can you plese let me know what is the problem in my code.

            SEAM component

            package com.sirs.action;

import org.jboss.seam.ScopeType;
import org.jboss.seam.annotations.In;
import org.jboss.seam.annotations.Name;
import org.jboss.seam.annotations.Out;
import org.jboss.seam.annotations.Scope;

@Name("assignCell")
@Scope(ScopeType.SESSION)
public class AssignCell {

 @In
 String bookName;

 @In @Out(scope=ScopeType.BUSINESS_PROCESS)
 String bookStatus;


 public void doAssignment() {

 System.out.println("Excecuting AssignCell action handler!!");

 int cell = Math.abs(bookName.hashCode() % 35);
 char block = (char)(Math.abs(bookName.hashCode() % 26) + 65);

 bookStatus = "Assigned to Block : " + block + " Cell : " + cell;

 }

}


            jPDL 
            <process-definition name="bbook">

 <start-state name="start">
 <transition to="assigncell"/>
 </start-state>

 <task-node name="assigncell">
 <transition to="breview">
 <action expression="#{assignCell.doAssignment}" />
 </transition>
 </task-node>

 <task-node name="breview">
 <task name="breview">
 <assignment actor-id="#{user.username}"/>
 </task>
 <transition to="done"/>
 </task-node>

 <end-state name="done"/>

</process-definition>


            The Exception I am getting 
            
09:34:33,203 ERROR [[Faces Servlet]] Servlet.service() for servlet Faces Servlet threw exception
javax.faces.FacesException: Error calling action method of component with id _id0:_id8
 at org.apache.myfaces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:74)
 at javax.faces.component.UICommand.broadcast(UICommand.java:106)
 at javax.faces.component.UIViewRoot._broadcastForPhase(UIViewRoot.java:90)
 at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:164)
 at org.apache.myfaces.lifecycle.LifecycleImpl.invokeApplication(LifecycleImpl.java:316)
 at org.apache.myfaces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:86)
 at javax.faces.webapp.FacesServlet.service(FacesServlet.java:106)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
 at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
 at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
 at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
 at org.jboss.web.tomcat.security.CustomPrincipalValve.invoke(CustomPrincipalValve.java:54)
 at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:174)
 at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:74)
 at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
 at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
 at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
 at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
 at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:868)
 at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:663)
 at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
 at org.apache.tomcat.util.net.MasterSlaveWorkerThread.run(MasterSlaveWorkerThread.java:112)
 at java.lang.Thread.run(Thread.java:595)
Caused by: javax.faces.el.EvaluationException: Exception while invoking expression #{bookingbean.saveBooking}
 at org.apache.myfaces.el.MethodBindingImpl.invoke(MethodBindingImpl.java:153)
 at org.apache.myfaces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:63)
 ... 25 more
Caused by: javax.ejb.EJBException: org.jbpm.graph.def.DelegationException
 at org.jboss.ejb3.tx.Ejb3TxPolicy.handleExceptionInOurTx(Ejb3TxPolicy.java:69)
 at org.jboss.aspects.tx.TxPolicy.invokeInOurTx(TxPolicy.java:83)
 at org.jboss.aspects.tx.TxInterceptor$Required.invoke(TxInterceptor.java:192)
 at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:98)
 at org.jboss.aspects.tx.TxPropagationInterceptor.invoke(TxPropagationInterceptor.java:76)
 at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:98)
 at org.jboss.ejb3.stateful.StatefulInstanceInterceptor.invoke(StatefulInstanceInterceptor.java:81)
 at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:98)
 at org.jboss.aspects.security.AuthenticationInterceptor.invoke(AuthenticationInterceptor.java:78)
 at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:98)
 at org.jboss.ejb3.ENCPropagationInterceptor.invoke(ENCPropagationInterceptor.java:47)
 at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:98)
 at org.jboss.ejb3.asynchronous.AsynchronousInterceptor.invoke(AsynchronousInterceptor.java:106)
 at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:98)
 at org.jboss.ejb3.stateful.StatefulContainer.localInvoke(StatefulContainer.java:190)
 at org.jboss.ejb3.stateful.StatefulLocalProxy.invoke(StatefulLocalProxy.java:98)
 at $Proxy262.saveBooking(Unknown Source)
 at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
 at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
 at java.lang.reflect.Method.invoke(Method.java:585)
 at org.apache.myfaces.el.MethodBindingImpl.invoke(MethodBindingImpl.java:129)
 ... 26 more
Caused by: org.jbpm.graph.def.DelegationException
 at org.jbpm.graph.def.GraphElement.raiseException(GraphElement.java:349)
 at org.jbpm.graph.def.GraphElement.raiseException(GraphElement.java:343)
 at org.jbpm.graph.def.GraphElement.executeAction(GraphElement.java:248)
 at org.jbpm.graph.def.GraphElement.executeActions(GraphElement.java:212)
 at org.jbpm.graph.def.GraphElement.fireAndPropagateEvent(GraphElement.java:182)
 at org.jbpm.graph.def.GraphElement.fireEvent(GraphElement.java:166)
 at org.jbpm.graph.def.Transition.take(Transition.java:106)
 at org.jbpm.graph.def.Node.leave(Node.java:382)
 at org.jbpm.graph.node.TaskNode.leave(TaskNode.java:198)
 at org.jbpm.graph.def.Node.leave(Node.java:346)
 at org.jbpm.graph.node.TaskNode.execute(TaskNode.java:188)
 at org.jbpm.graph.def.Node.enter(Node.java:316)
 at org.jbpm.graph.def.Node$$FastClassByCGLIB$$d187eeda.invoke(<generated>)
 at net.sf.cglib.proxy.MethodProxy.invoke(MethodProxy.java:149)
 at org.hibernate.proxy.CGLIBLazyInitializer.intercept(CGLIBLazyInitializer.java:161)
 at org.jbpm.graph.def.Node$$EnhancerByCGLIB$$9159ed05.enter(<generated>)
 at org.jbpm.graph.def.Transition.take(Transition.java:119)
 at org.jbpm.graph.def.Node.leave(Node.java:382)
 at org.jbpm.graph.node.StartState.leave(StartState.java:70)
 at org.jbpm.graph.node.StartState$$FastClassByCGLIB$$4ed4ed8c.invoke(<generated>)
 at net.sf.cglib.proxy.MethodProxy.invoke(MethodProxy.java:149)
 at org.hibernate.proxy.CGLIBLazyInitializer.intercept(CGLIBLazyInitializer.java:161)
 at org.jbpm.graph.node.StartState$$EnhancerByCGLIB$$d8598a37.leave(<generated>)
 at org.jbpm.graph.exe.Token.signal(Token.java:174)
 at org.jbpm.graph.exe.Token.signal(Token.java:123)
 at org.jbpm.graph.exe.ProcessInstance.signal(ProcessInstance.java:217)
 at org.jboss.seam.interceptors.BusinessProcessInterceptor.createProcess(BusinessProcessInterceptor.java:136)
 at org.jboss.seam.interceptors.BusinessProcessInterceptor.afterInvocation(BusinessProcessInterceptor.java:105)
 at org.jboss.seam.interceptors.BusinessProcessInterceptor.manageBusinessProcessContext(BusinessProcessInterceptor.java:58)
 at sun.reflect.GeneratedMethodAccessor292.invoke(Unknown Source)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
 at java.lang.reflect.Method.invoke(Method.java:585)
 at org.jboss.seam.util.Reflections.invoke(Reflections.java:13)
 at org.jboss.seam.interceptors.Interceptor.aroundInvoke(Interceptor.java:87)
 at org.jboss.seam.interceptors.SeamInvocationContext.proceed(SeamInvocationContext.java:60)
 at org.jboss.seam.interceptors.RemoveInterceptor.removeIfNecessary(RemoveInterceptor.java:38)
 at sun.reflect.GeneratedMethodAccessor291.invoke(Unknown Source)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
 at java.lang.reflect.Method.invoke(Method.java:585)
 at org.jboss.seam.util.Reflections.invoke(Reflections.java:13)
 at org.jboss.seam.interceptors.Interceptor.aroundInvoke(Interceptor.java:87)
 at org.jboss.seam.interceptors.SeamInvocationContext.proceed(SeamInvocationContext.java:60)
 at org.jboss.seam.ejb.SeamInterceptor.aroundInvoke(SeamInterceptor.java:41)
 at org.jboss.seam.interceptors.JavaBeanInterceptor.interceptInvocation(JavaBeanInterceptor.java:51)
 at org.jboss.seam.interceptors.JavaBeanInterceptor.intercept(JavaBeanInterceptor.java:39)
 at com.sirs.demo.control.ProcessStarter$$EnhancerByCGLIB$$84238875.startBurlingtonApprovalProcess(<generated>)
 at com.sirs.demo.data.BookingBean.saveBooking(BookingBean.java:102)
 at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
 at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
 at java.lang.reflect.Method.invoke(Method.java:585)
 at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:109)
 at org.jboss.ejb3.interceptor.InvocationContextImpl.proceed(InvocationContextImpl.java:168)
 at org.jboss.seam.interceptors.SeamInvocationContext.proceed(SeamInvocationContext.java:56)
 at org.jboss.seam.interceptors.ValidationInterceptor.validateTargetComponent(ValidationInterceptor.java:65)
 at sun.reflect.GeneratedMethodAccessor297.invoke(Unknown Source)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
 at java.lang.reflect.Method.invoke(Method.java:585)
 at org.jboss.seam.util.Reflections.invoke(Reflections.java:13)
 at org.jboss.seam.interceptors.Interceptor.aroundInvoke(Interceptor.java:87)
 at org.jboss.seam.interceptors.SeamInvocationContext.proceed(SeamInvocationContext.java:60)
 at org.jboss.seam.interceptors.OutcomeInterceptor.interceptOutcome(OutcomeInterceptor.java:21)
 at sun.reflect.GeneratedMethodAccessor296.invoke(Unknown Source)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
 at java.lang.reflect.Method.invoke(Method.java:585)
 at org.jboss.seam.util.Reflections.invoke(Reflections.java:13)
 at org.jboss.seam.interceptors.Interceptor.aroundInvoke(Interceptor.java:87)
 at org.jboss.seam.interceptors.SeamInvocationContext.proceed(SeamInvocationContext.java:60)
 at org.jboss.seam.interceptors.RollbackInterceptor.rollbackIfNecessary(RollbackInterceptor.java:30)
 at sun.reflect.GeneratedMethodAccessor295.invoke(Unknown Source)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
 at java.lang.reflect.Method.invoke(Method.java:585)
 at org.jboss.seam.util.Reflections.invoke(Reflections.java:13)
 at org.jboss.seam.interceptors.Interceptor.aroundInvoke(Interceptor.java:87)
 at org.jboss.seam.interceptors.SeamInvocationContext.proceed(SeamInvocationContext.java:60)
 at org.jboss.seam.interceptors.BijectionInterceptor.bijectTargetComponent(BijectionInterceptor.java:32)
 at sun.reflect.GeneratedMethodAccessor294.invoke(Unknown Source)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
 at java.lang.reflect.Method.invoke(Method.java:585)
 at org.jboss.seam.util.Reflections.invoke(Reflections.java:13)
 at org.jboss.seam.interceptors.Interceptor.aroundInvoke(Interceptor.java:87)
 at org.jboss.seam.interceptors.SeamInvocationContext.proceed(SeamInvocationContext.java:60)
 at org.jboss.seam.interceptors.ConversationInterceptor.endOrBeginLongRunningConversation(ConversationInterceptor.java:58)
 at sun.reflect.GeneratedMethodAccessor293.invoke(Unknown Source)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
 at java.lang.reflect.Method.invoke(Method.java:585)
 at org.jboss.seam.util.Reflections.invoke(Reflections.java:13)
 at org.jboss.seam.interceptors.Interceptor.aroundInvoke(Interceptor.java:87)
 at org.jboss.seam.interceptors.SeamInvocationContext.proceed(SeamInvocationContext.java:60)
 at org.jboss.seam.interceptors.BusinessProcessInterceptor.manageBusinessProcessContext(BusinessProcessInterceptor.java:58)
 at sun.reflect.GeneratedMethodAccessor292.invoke(Unknown Source)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
 at java.lang.reflect.Method.invoke(Method.java:585)
 at org.jboss.seam.util.Reflections.invoke(Reflections.java:13)
 at org.jboss.seam.interceptors.Interceptor.aroundInvoke(Interceptor.java:87)
 at org.jboss.seam.interceptors.SeamInvocationContext.proceed(SeamInvocationContext.java:60)
 at org.jboss.seam.interceptors.RemoveInterceptor.removeIfNecessary(RemoveInterceptor.java:38)
 at sun.reflect.GeneratedMethodAccessor291.invoke(Unknown Source)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
 at java.lang.reflect.Method.invoke(Method.java:585)
 at org.jboss.seam.util.Reflections.invoke(Reflections.java:13)
 at org.jboss.seam.interceptors.Interceptor.aroundInvoke(Interceptor.java:87)
 at org.jboss.seam.interceptors.SeamInvocationContext.proceed(SeamInvocationContext.java:60)
 at org.jboss.seam.ejb.SeamInterceptor.aroundInvoke(SeamInterceptor.java:41)
 at sun.reflect.GeneratedMethodAccessor290.invoke(Unknown Source)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
 at java.lang.reflect.Method.invoke(Method.java:585)
 at org.jboss.ejb3.interceptor.InvocationContextImpl.proceed(InvocationContextImpl.java:120)
 at org.jboss.ejb3.interceptor.EJB3InterceptorsInterceptor.invoke(EJB3InterceptorsInterceptor.java:62)
 at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:98)
 at org.jboss.ejb3.entity.ExtendedPersistenceContextPropagationInterceptor.invoke(ExtendedPersistenceContextPropagationInterceptor.java:57)
 at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:98)
 at org.jboss.ejb3.AllowedOperationsInterceptor.invoke(AllowedOperationsInterceptor.java:47)
 at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:98)
 at org.jboss.aspects.tx.TxPolicy.invokeInOurTx(TxPolicy.java:79)
 ... 46 more
Caused by: org.jbpm.JbpmException: couldn't evaluate expression '#{assignCell.doAssignment}'
 at org.jbpm.jpdl.el.impl.JbpmExpressionEvaluator.evaluate(JbpmExpressionEvaluator.java:37)
 at org.jbpm.graph.def.Action.execute(Action.java:119)
 at org.jbpm.graph.def.GraphElement.executeAction(GraphElement.java:235)
 ... 158 more
Caused by: org.jbpm.jpdl.el.ELException: An error occurred while invoking method "doAssignment" on an instance of class com.sirs.action.AssignCell$$En
hancerByCGLIB$$a98a7a22
 at org.jbpm.jpdl.el.impl.Logger.logError(Logger.java:485)
 at org.jbpm.jpdl.el.impl.Logger.logError(Logger.java:589)
 at org.jbpm.jpdl.el.impl.ArraySuffix.evaluate(ArraySuffix.java:290)
 at org.jbpm.jpdl.el.impl.ComplexValue.evaluate(ComplexValue.java:146)
 at org.jbpm.jpdl.el.impl.ExpressionEvaluatorImpl.evaluate(ExpressionEvaluatorImpl.java:264)
 at org.jbpm.jpdl.el.impl.ExpressionEvaluatorImpl.evaluate(ExpressionEvaluatorImpl.java:191)
 at org.jbpm.jpdl.el.impl.JbpmExpressionEvaluator.evaluate(JbpmExpressionEvaluator.java:34)
 ... 160 more



            Thanks,
            Raghu.

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            • 3. Re: BPM Variable Injection
              gavin.king
              gavin.king Apr 5, 2006 10:03 AM (in response to go_rags)

              Dunno, the stack trace is not showing the underlying exception. Use your debugger to find the deepest exception.

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