jBPM4.4开发（九）-----------HQL,SQL节点

HQL节点

1.定义

hql活动能够支持使用hql直接从数据库中查询数据，并将结果返回到流程变量中。

2.hql活动属性

var   存储hql执行结果的流程变量名称。
unique  此属性为true时，返回结果为一行，结果将作为一个单独的对象存储；此属性为false时，返回结果为多行，结果将作为一个Set存储。

3.hql活动的子元素

query   用来设置hql查询语句。
parameters  用来设置hql的外部参数。

4.Demo

流程定义文件：process.jpdl.xml

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

<process name="Hql" xmlns="http://jbpm.org/4.4/jpdl">

<start g="17,20,48,48">
<transition to="get task names" />
</start>

<hql name="get task names"
var="tasknames with i"
g="96,16,115,52">
<query>
select task.name
from org.jbpm.pvm.internal.task.TaskImpl as task
where task.name like :taskName
</query>
<parameters>
<string name="taskName" value="%i%" />
</parameters>
<transition to="count tasks" />
</hql>

<hql name="count tasks"
var="tasks"
unique="true"
g="243,16,95,52">
<query>
select count(*)
from org.jbpm.pvm.internal.task.TaskImpl
</query>
<transition to="wait" />
</hql>

<state name="wait" g="370,18,96,48"/>

</process>

测试类：HqlTest.java

package com.itstudio.jbpm.hql.demo;

import java.util.Collection;
import java.util.HashSet;
import java.util.Set;

import org.jbpm.api.Configuration;
import org.jbpm.api.ExecutionService;
import org.jbpm.api.ProcessEngine;
import org.jbpm.api.ProcessInstance;
import org.jbpm.api.RepositoryService;
import org.jbpm.api.TaskService;
import org.jbpm.api.task.Task;

public class HqlTest {
public  final Configuration configuration = new Configuration();
public  final ProcessEngine processEngine=configuration.buildProcessEngine();
public  final RepositoryService repositoryService= processEngine.getRepositoryService();
public  final ExecutionService executionService=processEngine.getExecutionService();
public  final TaskService taskService=processEngine.getTaskService();

String taskLaundryId;
String taskDishesId;
String taskIronId;

private void deploy() {
repositoryService.createDeployment().addResourceFromClasspath(
"com/itstudio/jbpm/hql/demo/process.jpdl.xml").deploy();
System.out.println("Successful!");
// add task laundry
Task task = taskService.newTask();
task.setName("laundry");
taskLaundryId = taskService.saveTask(task);

// add task dishes
task = taskService.newTask();
task.setName("dishes");
taskDishesId = taskService.saveTask(task);

// add task iron
task = taskService.newTask();
task.setName("iron");
taskIronId = taskService.saveTask(task);
}

private void test() {
ProcessInstance processInstance = executionService
.startProcessInstanceByKey("Hql");
String processInstanceId = processInstance.getId();

Set<String> expectedTaskNames = new HashSet<String>();
expectedTaskNames.add("dishes");
expectedTaskNames.add("iron");
Collection<String> taskNames = (Collection<String>) executionService
.getVariable(processInstanceId, "tasknames with i");
taskNames = new HashSet<String>(taskNames);
System.out.println("expectedTaskNames:"+expectedTaskNames);
System.out.println("taskNames"+taskNames);

Object activities = executionService.getVariable(processInstanceId,
"tasks");
System.out.println("activities"+activities.toString());

}

public static void main(String[] args) {
HqlTest t = new HqlTest();
t.deploy();
t.test();
}
}

5.sql与hql类似

请参照开发文档

By Mr.Z