1 Reply Latest reply on Oct 12, 2012 4:46 AM by saig0

    XOR Gateway

    tmmaluleke Newbie

      Hello,

       

      I have a project which have the XOR gateway en when I run it its gives me this error:

       

      This is what I coded in my XOR gateway:

       

      if(studentId !="null"); the process must continue or if(studentId =="null"); the process must alert the user to input the studentId. but when I run this error occurs.

       

       

      Exception in thread "Thread-4" org.jbpm.workflow.instance.WorkflowRuntimeException: [validatingStudentId.bpmn:1 - Gateway:5] -- Exception when trying to evaluate constraint Accept in split Gateway

          at org.jbpm.workflow.instance.impl.NodeInstanceImpl.trigger(NodeInstanceImpl.java:130)

          at org.jbpm.workflow.instance.impl.NodeInstanceImpl.triggerNodeInstance(NodeInstanceImpl.java:205)

          at org.jbpm.workflow.instance.impl.NodeInstanceImpl.triggerCompleted(NodeInstanceImpl.java:164)

          at org.jbpm.workflow.instance.impl.ExtendedNodeInstanceImpl.triggerCompleted(ExtendedNodeInstanceImpl.java:47)

          at org.jbpm.workflow.instance.node.StateBasedNodeInstance.triggerCompleted(StateBasedNodeInstance.java:162)

          at org.jbpm.workflow.instance.node.StateBasedNodeInstance.triggerCompleted(StateBasedNodeInstance.java:143)

          at org.jbpm.workflow.instance.node.WorkItemNodeInstance.triggerCompleted(WorkItemNodeInstance.java:239)

          at org.jbpm.workflow.instance.node.HumanTaskNodeInstance.triggerCompleted(HumanTaskNodeInstance.java:90)

          at org.jbpm.workflow.instance.node.WorkItemNodeInstance.workItemCompleted(WorkItemNodeInstance.java:301)

          at org.jbpm.workflow.instance.node.WorkItemNodeInstance.signalEvent(WorkItemNodeInstance.java:277)

          at org.jbpm.workflow.instance.impl.WorkflowProcessInstanceImpl.signalEvent(WorkflowProcessInstanceImpl.java:326)

          at org.drools.process.instance.impl.DefaultWorkItemManager.completeWorkItem(DefaultWorkItemManager.java:116)

          at org.jbpm.process.workitem.wsht.GenericHTWorkItemHandler$TaskCompletedHandler.handleCompletedTask(GenericHTWorkItemHandler.java:221)

          at org.jbpm.process.workitem.wsht.GenericHTWorkItemHandler$TaskCompletedHandler$1.run(GenericHTWorkItemHandler.java:187)

          at java.lang.Thread.run(Unknown Source)

      Caused by: java.lang.RuntimeException: Exception when trying to evaluate constraint Accept in split Gateway

          at org.jbpm.workflow.instance.node.SplitInstance.internalTrigger(SplitInstance.java:79)

          at org.jbpm.workflow.instance.impl.NodeInstanceImpl.trigger(NodeInstanceImpl.java:124)

          ... 14 more

      Caused by: java.lang.RuntimeException: unable to execute ReturnValueEvaluator

          at org.jbpm.process.instance.impl.ReturnValueConstraintEvaluator.evaluate(ReturnValueConstraintEvaluator.java:130)

          at org.jbpm.workflow.instance.node.SplitInstance.internalTrigger(SplitInstance.java:72)

          ... 15 more

      Caused by: java.lang.RuntimeException: Constraints must return boolean values: if(studentId !=" null"); returns null

          at org.jbpm.process.instance.impl.MVELReturnValueEvaluator.evaluate(MVELReturnValueEvaluator.java:119)

          at org.jbpm.process.instance.impl.ReturnValueConstraintEvaluator.evaluate(ReturnValueConstraintEvaluator.java:128)

          ... 16 more