@Deployment public void test(){
  ProcessInstance pi=runtimeService.startProcessInstanceByKey("skipExpressionUserTask");
  List<Task> tasks=taskService.createTaskQuery().list();
  assertEquals(1,tasks.size());
  taskService.complete(tasks.get(0).getId());
  assertEquals(0,taskService.createTaskQuery().list().size());
  Map<String,Object> variables2=new HashMap<String,Object>();
  variables2.put("_ACTIVITI_SKIP_EXPRESSION_ENABLED",true);
  variables2.put("skip",false);
  runtimeService.startProcessInstanceByKey("skipExpressionUserTask",variables2);
  List<Task> tasks2=taskService.createTaskQuery().list();
  assertEquals(1,tasks2.size());
  taskService.complete(tasks2.get(0).getId());
  assertEquals(0,taskService.createTaskQuery().list().size());
  Map<String,Object> variables3=new HashMap<String,Object>();
  variables3.put("_ACTIVITI_SKIP_EXPRESSION_ENABLED",true);
  variables3.put("skip",true);
  ProcessInstance pi3=runtimeService.startProcessInstanceByKey("skipExpressionUserTask",variables3);
  List<Task> tasks3=taskService.createTaskQuery().list();
  assertEquals(0,tasks3.size());
}
