JBPM4.4(2)-state结点和decision结点

做一个带有分支的流向流程

在执行seperate状态的时候分成了200和400两种情况

描述文件的内容如下：

View Code

<? xml version="1.0" encoding="UTF-8" ?>

< process name ="fork" xmlns ="http://jbpm.org/4.4/jpdl" >
< start g ="237,28,48,48" name ="start1" >
< transition name ="to separate" to ="separate" g ="-71,-17" />
</ start >
< state g ="210,153,92,52" name ="separate" >
< transition name ="to 200" to ="200" g ="-41,-17" />
< transition name ="to 400" to ="400" g ="-41,-17" />
</ state >
< state g ="145,256,92,52" name ="200" >
< transition name ="to end1" to ="end1" g ="-47,-17" />
</ state >
< state g ="306,255,92,52" name ="400" >
< transition name ="to end1" to ="end1" g ="-47,-17" />
</ state >
< end g ="245,375,48,48" name ="end1" />
</ process >

测试代码如下：

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public class TestSperator extends JbpmTestCase {

String deploymentId;

protected void setUp() throws Exception {
super .setUp();

deploymentId = repositoryService.createDeployment()
.addResourceFromClasspath( " com/jbpm/fork/fork.jpdl.xml " )
.deploy();
}

protected void tearDown() throws Exception {
repositoryService.deleteDeploymentCascade(deploymentId);

super .tearDown();
}

public void testSeparate() {
ProcessInstance processInstance = executionService
.startProcessInstanceByKey( " fork " );

System.out.println( " 流程实例Id: " + processInstance.getId());
System.out.println( " 流程定义Id: " + processInstance.getProcessDefinitionId());

ProcessInstance instance = executionService.signalExecutionById(processInstance.getId());

// 判断当前是否位于state节点

System.out.println( " 是否位于state节点: " + instance.isActive( " separate " ));
System.out.println( " 向下执行... " );

ProcessInstance processInstance200 = executionService.signalExecutionById(processInstance.getId(), " to 200 " );

System.out.println( " 当前流程是否位于200节点----> " + processInstance200.isActive( " 200 " ));
System.out.println( " 当前流程是否结束----> " + processInstance200.isEnded());

ProcessInstance endinstance = executionService.signalExecutionById(processInstance200.getId());

System.out.println( " 当前流程是否结束----> " + endinstance.isEnded());


}
}

执行流程的结果如下：

使流程向下执行

executionService.signalExecutionById();

该方法有多个重载:

注:当一个节点有多个分支时,若要通过signalExecutionById()方法将流程向下执行必须明确指出signalName即(transition的name属性所指的方向),否则流程不会向下执行，仍会停留在当前节点。因为jbpm不确定流程该流向那个方向。

接下来是一个decision的例子，这个是一个分支判断的节点，相当于我们程序中的switch case

下面画一个选择向左还是向右的例子

定义文件如下：

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<? xml version="1.0" encoding="UTF-8" ?>

< process name ="decision" xmlns ="http://jbpm.org/4.4/jpdl" >
< start g ="246,30,48,48" name ="start1" >
< transition name ="to wait" to ="wait" g ="-47,-17" />
</ start >
< state g ="231,112,92,52" name ="wait" >
< transition name ="to exclusive1" to ="exclusive1" g ="-83,-17" />
</ state >
< decision g ="252,204,48,48" name ="exclusive1" >
< transition name ="to left" to ="left" g ="-47,-17" >
< condition expr ="${coder=='left'}" ></ condition >
</ transition >
< transition name ="to right" to ="right" g ="-53,-17" >
< condition expr ="${coder=='right'}" ></ condition >
</ transition >
</ decision >
< state g ="175,295,92,52" name ="left" >
< transition name ="to end1" to ="end1" g ="-47,-17" />
</ state >
< state g ="325,292,92,52" name ="right" >
< transition name ="to end1" to ="end1" g ="-47,-17" />
</ state >
< end g ="268,370,48,48" name ="end1" />
</ process >

其中有几种方式可以处理流程的走向

即在流程定义中设置每一个transition的子节点condition,并为每一个condition填充expr属性

形如:

<condition expr="${coder=='left'}"></condition>

对应的测试流程如下，需要增加

View Code

Map < String, String > map = new HashMap < String, String > ();
// coder为流程定义中表达式的名称
map.put( " coder " , " left " );

ProcessInstance processInstance = executionService.startProcessInstanceByKey( " decision " ,map);

如果map中order的值指定的有问题那么就会抛出异常

测试程序如下：

View Code

public class TestDecision extends JbpmTestCase {

String deploymentId;

protected void setUp() throws Exception {
super .setUp();

deploymentId = repositoryService.createDeployment()
.addResourceFromClasspath( " com/jbpm/decision/decision.jpdl.xml " )
.deploy();
}

protected void tearDown() throws Exception {
repositoryService.deleteDeploymentCascade(deploymentId);

super .tearDown();
}

public void testDescsion() {

Map < String, String > map = new HashMap < String, String > ();
// coder为流程定义中表达式的名称
map.put( " coder " , " left " );

ProcessInstance processInstance = executionService.startProcessInstanceByKey( " decision " ,map);

System.out.println( " 流程实例Id: " + processInstance.getId());
System.out.println( " 流程定义Id: " + processInstance.getProcessDefinitionId());

System.out.println( " 是否位于state节点: " + processInstance.isActive( " wait " ));

ProcessInstance decisionInstance = executionService.signalExecutionById(processInstance.getId());

// 判断当前是否位于wait节点
System.out.println( " 是否位于wait节点: " + decisionInstance.isActive( " wait " ));
System.out.println( " 因为已经有值所以自动向下执行... " );
System.out.println( " 是否位于left节点: " + decisionInstance.isActive( " left " ));

// 向下执行
ProcessInstance endinstance = executionService.signalExecutionById(decisionInstance.getId());

System.out.println( " 当前流程是否结束----> " + endinstance.isEnded());

}
}

执行结果如图所示：

因为在开始的时候指定了流程处理的方向，所以流程向left方向自动执行。

在decision节点上指定

<decision g="252,204,48,48" name="exclusive1" expr="${toWhere}">

修改代码为：

View Code

Map < String, String > map = new HashMap < String, String > ();
// coder为流程定义中表达式的名称
map.put( " toWhere " , " to left " );

其它部分不变，可以看到结果和原来的相同。

第三种，配置handler子类

在流程定义中在decision节点内部配置<handler/>子节点,并设置该元素的class属性为你自己的类)该类实现了org.jbpm.api.jpdl.DecisionHandler.你需要重写

String decide(OpenExecution execution);方法即可,在该方法最终返回decision活动后的下一个transition的name属性的值。

修改配置文件

View Code

< decision g ="252,204,48,48" name ="exclusive1" >
< handler class ="com.jbpm.decision.HandlerDecision" ></ handler >
< transition name ="to left" to ="left" g ="-47,-17" >
</ transition >
< transition name ="to right" to ="right" g ="-53,-17" >
</ transition >
</ decision >

添加HandlerDecision并且实现DecisionHandler

代码如下：

View Code

@SuppressWarnings( " serial " )
public class HandlerDecision implements DecisionHandler {

@Override
public String decide(OpenExecution execution) {
// TODO Auto-generated method stub
String toWhere = execution.getVariable( " toWhere " ).toString();
String result = null ;

if ( " left " .equals(toWhere)) {
result = " to left " ;
} else if ( " right " .equals(toWhere)) {
result = " to right " ;
}
return result;
}

}

测试代码只需将map中的值进行简单修改即可