ProcessDefinition Xml-String:

String xml = "<?xml version='1.0' encoding='GBK'?>"
+" <process-definition xmlns=\"urn:jbpm.org:jpdl-3.1\" name=\"流程定义1\">"
+" <start-state name='开始'>"
+" <transition name=\"\" to=\"task1\"></transition>"
+" </start-state>"
+" <task-node name=\"task1\">"
+" <task name=\"ade\"></task>"
+" <transition name=\"\" to=\"decision1\"></transition>"
+" </task-node>"
+" <decision name=\"decision1\" expression=\"#{SP=='Y'?'true':'false'}\">"
+" <transition name=\"true\" to=\"state100\"></transition>"
+" <transition name=\"false\" to=\"state200\"></transition>"
+" </decision>"
+" <state name=\"state100\">"
+" <transition name=\"\" to=\"end1\"></transition>"
+" </state>"
+" <state name=\"state200\">"
+" <transition name=\"\" to=\"end2\"></transition>"
+" </state>"
+" <end-state name=\"end1\"></end-state>"
+" <end-state name=\"end2\"></end-state>"

+" </process-definition>";

//------------------------------------------------------
processDefinition = ProcessDefinition.parseXmlString(xml);
cxt.deployProcessDefinition(processDefinition);
instance = new ProcessInstance(processDefinition);
System.out.println("pd-id:"+processDefinition.getId()); //678,
System.out.println("pi-id:"+instance.getId()); //678,1725

//instance = cxt.getProcessInstance(4959);
Token root = instance.getRootToken();
root.signal();
ExecutionContext ec = new ExecutionContext(root);
instance.getContextInstance().setVariable("SP", "Y");
System.out.println("root::"+getGBK(root.getNode().getName())+instance.getId());
Node node2 = ((Transition)root.getNode().getLeavingTransitions().iterator().next()).getTo();
String xx = null;
System.out.println("root::"+getGBK(root.getNode().getName())+instance.getId());
List Nodelist = root.getNode().getLeavingTransitions();
for (int i = 0; i < Nodelist.size(); i++) {
Transition tran = (Transition) Nodelist.get(0);
Node node = tran.getTo();

if(node instanceof Decision){
Decision de = (Decision)node;
xx = de.execute_X(ec);
System.out.println("dec_: "+xx);
}
System.out.println(getGBK(node.getName()));
}

Result:
root::task15157
root::task15157
dec_: true
decision1

//------------------------------------------------------
instance = cxt.getProcessInstance(4959);
Token root = instance.getRootToken();
//root.signal();
ExecutionContext ec = new ExecutionContext(root);
instance.getContextInstance().setVariable("SP", "Y");
System.out.println("root::"+getGBK(root.getNode().getName())+instance.getId());
Node node2 = ((Transition)root.getNode().getLeavingTransitions().iterator().next()).getTo();
String xx = null;
System.out.println("root::"+getGBK(root.getNode().getName())+instance.getId());
List Nodelist = root.getNode().getLeavingTransitions();
for (int i = 0; i < Nodelist.size(); i++) {
Transition tran = (Transition) Nodelist.get(0);
Node node = tran.getTo();
//这里的Decision节点无法还原? 为什么呢?
if(node instanceof Decision){
Decision de = (Decision)node;
xx = de.execute_X(ec);
System.out.println("dec_: "+xx);
}
System.out.println(getGBK(node.getName()));
}

Result:
root::task14959
root::task14959
decision1
//------------------------------------------------------------------------
急...

xx = de.execute_X(ec); 中的方法为验证Decision中的表达式的返回值.
    当流程实例创建保存到数据库后.第二次跟据流程实例ID取得的节点.无法还原原有类型.
    发现从数据库中取出的节点.包括TaskNode,Decision...全部成了Node类型,而且没法转换回来,
    郁闷中...
    不知道是我理解错了,还是事实如此,希望那位朋友给指点一下.

TaskNode taskNode = (TaskNode)(jbpmContext.getSession().load(TaskNode.class, token.getNode().getId()));

非常感谢,~~   结贴~ ^_^