jbpm4.4 报错 no process definition with key

[laoankang]

这是工程结构
public class ProcessInstanceTest extends TestCase {

ProcessEngine processEngine;

public ProcessInstanceTest(){
processEngine = Configuration.getProcessEngine();
}

protected void SetUp() {
processEngine.getRepositoryService().createDeployment()
.addResourceFromClasspath("helloword.jpdl.xml").deploy();
}

public void testProcessInstance(){
ExecutionService executionService = processEngine.getExecutionService();
ProcessInstance pi = executionService.startProcessInstanceByKey("helloword");
}
}

executionService.startProcessInstanceByKey("helloword");
报错no process definition with key
跪求，这个怎么解决？