persistent execution mode

[galanfish]

can anyone give me a persistent execution mode program demo?
i have been stucked..

my testcase and exception jvm method call stack as follow:

public class PersistentExecutionModeTest extends EnvironmentFactoryTestCase {

 public void testDeploy() { // seems ok
// /*
 JbpmConfiguration environmentFactory = (JbpmConfiguration)getEnvironmentFactory();
 ProcessService processService = environmentFactory.get(ProcessService.class);

 ClientProcessDefinition processDefinition = ProcessDefinitionBuilder
 .startProcess("test")

 .startActivity("start", WaitState.class)
 .initial()
 .flow("end","end")
 .endActivity()

 .startActivity("end", AutomaticActivity.class)
 .endActivity()

 .endProcess();

 Deployment deployment = new DeploymentImpl();
 deployment.addObject("testProcesssss", processDefinition);

 ((ProcessServiceImpl) processService).deploy(deployment);
// */
 }

 public void testStartProcessInstance() { // seems ok, 2

 JbpmConfiguration environmentFactory = (JbpmConfiguration) getEnvironmentFactory();
 ExecutionService executionService = environmentFactory.get(ExecutionService.class);
 Execution execution = executionService.startProcessInstanceById("test:1", "request17");
 }

 public void testResumeProcessInstance(){ // something wrong...
 JbpmConfiguration environmentFactory = (JbpmConfiguration)getEnvironmentFactory();
 ExecutionService executionService = environmentFactory.get(ExecutionService.class);
 Execution execution = executionService.signalExecutionById("test/request17", "end"); // exception occured here

 }

}

exception:
Hibernate:
/* delete org.jbpm.pvm.internal.model.ExecutionImpl */ delete
from
JBPM_EXECUTION
where
DBID_=?
and DBVERSION_=?
10:36:37,578 WRN | [JDBCExceptionReporter] SQL Error: 1451, SQLState: 23000
10:36:37,578 SEV | [JDBCExceptionReporter] Cannot delete or update a parent row: a foreign key constraint fails (`jbpm_pvm/jbpm_execution`, CONSTRAINT `FK_EXEC_INSTANCE` FOREIGN KEY (`INSTANCE_`) REFERENCES `jbpm_execution` (`DBID_`))
### EXCEPTION ###########################################
10:36:37,578 SEV | [AbstractFlushingEventListener] Could not synchronize database state with session
org.hibernate.exception.ConstraintViolationException: could not delete: [org.jbpm.pvm.internal.model.ExecutionImpl#4]
at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:71)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:43)
at org.hibernate.persister.entity.AbstractEntityPersister.delete(AbstractEntityPersister.java:2546)
at org.hibernate.persister.entity.AbstractEntityPersister.delete(AbstractEntityPersister.java:2702)
at org.hibernate.action.EntityDeleteAction.execute(EntityDeleteAction.java:77)
at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:279)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:263)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:172)
at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:298)
at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:27)
at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1000)
at org.jbpm.pvm.internal.tx.HibernateSessionResource.prepare(HibernateSessionResource.java:54)
at org.jbpm.pvm.internal.tx.StandardTransaction.commit(StandardTransaction.java:106)
at org.jbpm.pvm.internal.tx.StandardTransaction.complete(StandardTransaction.java:65)
at org.jbpm.pvm.internal.tx.StandardTransactionInterceptor.execute(StandardTransactionInterceptor.java:61)
at org.jbpm.pvm.internal.svc.EnvironmentInterceptor.execute(EnvironmentInterceptor.java:40)
at org.jbpm.pvm.internal.svc.RetryInterceptor.execute(RetryInterceptor.java:52)
at org.jbpm.pvm.internal.model.ProcessInstanceEndedSynchronization.afterCompletion(ProcessInstanceEndedSynchronization.java:52)
at org.jbpm.pvm.internal.tx.StandardSynchronization.afterCompletion(StandardSynchronization.java:41)
at org.jbpm.pvm.internal.tx.StandardTransaction.afterCompletion(StandardTransaction.java:213)
at org.jbpm.pvm.internal.tx.StandardTransaction.commit(StandardTransaction.java:153)
at org.jbpm.pvm.internal.tx.StandardTransaction.complete(StandardTransaction.java:65)
at org.jbpm.pvm.internal.tx.StandardTransactionInterceptor.execute(StandardTransactionInterceptor.java:61)
at org.jbpm.pvm.internal.svc.EnvironmentInterceptor.execute(EnvironmentInterceptor.java:40)
at org.jbpm.pvm.internal.svc.RetryInterceptor.execute(RetryInterceptor.java:52)
at org.jbpm.pvm.internal.svc.ExecutionServiceImpl.signalExecutionById(ExecutionServiceImpl.java:97)
at org.jbpm.pvm.executionmode.persistence.PersistentExecutionModeTest.testResumeProcessInstance(PersistentExecutionModeTest.java:81)
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 junit.framework.TestCase.runTest(TestCase.java:164)
at org.jbpm.test.BaseJbpmTestCase.runTest(BaseJbpmTestCase.java:81)
at junit.framework.TestCase.runBare(TestCase.java:130)
at junit.framework.TestResult$1.protect(TestResult.java:106)
at junit.framework.TestResult.runProtected(TestResult.java:124)
at junit.framework.TestResult.run(TestResult.java:109)
at junit.framework.TestCase.run(TestCase.java:120)
at junit.framework.TestSuite.runTest(TestSuite.java:230)
at junit.framework.TestSuite.run(TestSuite.java:225)
at org.eclipse.jdt.internal.junit.runner.junit3.JUnit3TestReference.run(JUnit3TestReference.java:130)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:460)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:673)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:386)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:196)