JBoss 系列七十五： jBPM 6 示例之 rewards

概述

如上篇（使用 BPMN2 Modeler 创建 jBPM 6 流程）中所示，我们演示通过 jBPM 6 eclipse 插件如何 step by step 的创建 BPMN2 流程，我们最终创建的流程如下：

我们将如上流程称作为 jBPM Rewards流程，即请求者提出申请一个奖励，流程开始，申请奖励的请求首先被PM允许，接着被HR允许，流程结束，请求者得到奖励。从流程的角度去说，rewards流程包括6个节点：

• Start - 流程开始事件，表示rewards流程开始
• Start - Script Task 节点，流程运行此节点时执行Script ，Start  Script 为java代码（参照使用 BPMN2 Modeler 创建 jBPM 6 流程），即流程运行此节点时执行java代码段
• Approval by PM - Human task 节点，即流程运行此节点必须有人为参与才能够完成，本处 john 扮演PM的角色来完成此节点
• Approval by HR - Human task 节点，即流程运行此节点必须有人为参与才能够完成，本处 mary 扮演HR的角色来完成此节点
• End - Script Task 节点，流程运行此节点时执行Script ，End Script 为java代码（参照使用 BPMN2 Modeler 创建 jBPM 6 流程），即流程运行此节点时执行java代码段
• End - 流程结束事件，表示rewards流程运行结束

如上流程位于： https://github.com/kylinsoong/jbpm-6-examples/blob/master/rewards/src/main/resources/org/jbpm/demo/rewards.bpmn

本示例主要内容可以概括为：

• 运行 jBPM 6 Human tasks
• 数据存储（JPA）
• 使用 Maven 快速构建 jBPM 6 测试工程

运行 jBPM 6 Human tasks

我们通过如下几步来运行jBPM 6 rewards示例。

rewards.bpmn（使用 BPMN2 Modeler 创建 jBPM 6 流程中设计）位于classpath中org/jbpm/demo目录下。

kmodule.xml 位于classpath 中 META-INF下，内容如下所示：

<kmodule xmlns="http://jboss.org/kie/6.0.0/kmodule">
	<kbase name="kbase" packages="org.jbpm.demo" />
</kmodule>

使用ProcessMain运行rewards流程，ProcessMain内容如下所示：

package org.jbpm.demo.rewards;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;

import org.jbpm.test.JBPMHelper;
import org.kie.api.KieBase;
import org.kie.api.KieServices;
import org.kie.api.runtime.KieContainer;
import org.kie.api.runtime.KieSession;
import org.kie.api.runtime.manager.RuntimeEngine;
import org.kie.api.runtime.manager.RuntimeEnvironmentBuilder;
import org.kie.api.runtime.manager.RuntimeManager;
import org.kie.api.runtime.manager.RuntimeManagerFactory;
import org.kie.api.task.TaskService;
import org.kie.api.task.model.TaskSummary;

public class ProcessMain {

	public static void main(String[] args) {
		
		KieServices ks = KieServices.Factory.get();
		KieContainer kContainer = ks.getKieClasspathContainer();
		KieBase kbase = kContainer.getKieBase("kbase");

		RuntimeManager manager = createRuntimeManager(kbase);
		RuntimeEngine engine = manager.getRuntimeEngine(null);
		KieSession ksession = engine.getKieSession();
		TaskService taskService = engine.getTaskService();

		Map<String, Object> params = new HashMap<String, Object>();
        params.put("recipient", "kylin");
        ksession.startProcess("org.jbpm.demo.rewards", params);
        
		// let john execute Task 1
		List<TaskSummary> list = taskService.getTasksAssignedAsPotentialOwner("john", "en-UK");
		TaskSummary task = list.get(0);
		taskService.start(task.getId(), "john");
		taskService.complete(task.getId(), "john", null);

		// let mary execute Task 2
		list = taskService.getTasksAssignedAsPotentialOwner("mary", "en-UK");
		task = list.get(0);
		taskService.start(task.getId(), "mary");
		taskService.complete(task.getId(), "mary", null);

		manager.disposeRuntimeEngine(engine);
		
		System.exit(0);
	}

	private static RuntimeManager createRuntimeManager(KieBase kbase) {
		JBPMHelper.startH2Server();
		JBPMHelper.setupDataSource();
		EntityManagerFactory emf = Persistence.createEntityManagerFactory("org.jbpm.persistence.jpa");
		RuntimeEnvironmentBuilder builder = RuntimeEnvironmentBuilder.Factory.get().newDefaultBuilder().entityManagerFactory(emf).knowledgeBase(kbase);
		return RuntimeManagerFactory.Factory.get().newSingletonRuntimeManager(builder.get(), "com.sample:example:1.0");
	}

}

该代码位于： https://github.com/kylinsoong/jbpm-6-examples/blob/master/rewards/src/main/java/org/jbpm/demo/rewards/ProcessMain.java

运行ProcessMain会有如下输出：

process 33 started by kylin
john approved process 33
mary approved process 33
process 33 finished

数据存储（JPA）

如上运行过程中我们使用到H2数据库存储运行过程中的数据，jBPM 6通过JPA/hibernate来操作数据库，RuntimeEnvironmentBuilder中传入创建的EntityManagerFactory（org.jbpm.persistence.jpa），我们可以在jbpm-test-6.0.0.Final.jar中找到JPA persist-unit的定义，persistence.xml位于jbpm-test-6.0.0.Final.jar/META-INF下，内容如下：

<persistence 
  version="2.0"
  xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd
                      http://java.sun.com/xml/ns/persistence/orm http://java.sun.com/xml/ns/persistence/orm_2_0.xsd"
  xmlns:orm="http://java.sun.com/xml/ns/persistence/orm"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xmlns="http://java.sun.com/xml/ns/persistence">

  <persistence-unit name="org.jbpm.persistence.jpa" transaction-type="JTA">
    <provider>org.hibernate.ejb.HibernatePersistence</provider>
    <jta-data-source>jdbc/jbpm-ds</jta-data-source>        
    
    <mapping-file>META-INF/JBPMorm.xml</mapping-file>
    <mapping-file>META-INF/Taskorm.xml</mapping-file>
    
    <class>org.jbpm.persistence.processinstance.ProcessInstanceInfo</class>
    <class>org.drools.persistence.info.SessionInfo</class>
    <class>org.drools.persistence.info.WorkItemInfo</class>

    <class>org.jbpm.process.audit.ProcessInstanceLog</class>
    <class>org.jbpm.process.audit.NodeInstanceLog</class>
    <class>org.jbpm.process.audit.VariableInstanceLog</class>
    
    <class>org.jbpm.persistence.correlation.CorrelationKeyInfo</class>
    <class>org.jbpm.persistence.correlation.CorrelationPropertyInfo</class>
    
    <!-- manager -->
    <class>org.jbpm.runtime.manager.impl.jpa.ContextMappingInfo</class>
    
    <class>org.jbpm.services.task.impl.model.AttachmentImpl</class>
    <class>org.jbpm.services.task.impl.model.ContentImpl</class>
    <class>org.jbpm.services.task.impl.model.BooleanExpressionImpl</class>
    <class>org.jbpm.services.task.impl.model.CommentImpl</class>
    <class>org.jbpm.services.task.impl.model.DeadlineImpl</class>
    <class>org.jbpm.services.task.impl.model.CommentImpl</class>
    <class>org.jbpm.services.task.impl.model.DeadlineImpl</class>
    <class>org.jbpm.services.task.impl.model.DelegationImpl</class>
    <class>org.jbpm.services.task.impl.model.EscalationImpl</class>
    <class>org.jbpm.services.task.impl.model.GroupImpl</class>
    <class>org.jbpm.services.task.impl.model.I18NTextImpl</class>
    <class>org.jbpm.services.task.impl.model.NotificationImpl</class>
    <class>org.jbpm.services.task.impl.model.EmailNotificationImpl</class>
    <class>org.jbpm.services.task.impl.model.EmailNotificationHeaderImpl</class>
    <class>org.jbpm.services.task.impl.model.PeopleAssignmentsImpl</class>
    <class>org.jbpm.services.task.impl.model.ReassignmentImpl</class>
    
    <class>org.jbpm.services.task.impl.model.TaskImpl</class>
    <class>org.jbpm.services.task.impl.model.TaskDataImpl</class>
    <class>org.jbpm.services.task.impl.model.UserImpl</class>
    
    <!--BAM for task service -->
    <class>org.jbpm.services.task.impl.model.BAMTaskSummaryImpl</class>
    
    
    <properties>
      <property name="hibernate.max_fetch_depth" value="3"/>
      <property name="hibernate.hbm2ddl.auto" value="update" />
      <property name="hibernate.show_sql" value="false" />	
      <property name="hibernate.dialect" value="org.hibernate.dialect.H2Dialect"/>

      <!-- BZ 841786: AS7/EAP 6/Hib 4 uses new (sequence) generators which seem to cause problems -->      
      <property name="hibernate.id.new_generator_mappings" value="false" />            

      <property name="hibernate.transaction.jta.platform" value="org.hibernate.service.jta.platform.internal.BitronixJtaPlatform" />
    </properties>        
  </persistence-unit>
    
</persistence>

使用 Maven 快速构建 jBPM 6 测试工程

本示例还演示了如何使用 Maven 快速构建 jBPM 6 测试工程，创建 jBPM 6 测试工程只需要依赖一个依赖包：

<dependency>
			<groupId>org.jbpm</groupId>
			<artifactId>jbpm-test</artifactId>
			<version>${jbpm.version}</version>
		</dependency>

org.jbpm.test.JbpmJUnitBaseTestCase提供了构造方法的createRuntimeManager（）方法快速构建运行jBPM 6 Human tasks环境，在之前版本的jBPM(如jBPM 5)中，我们需要自己创建datasource，创建TaskService，jBPM 6中简化了这些操作，提供了RuntimeManager，我们可以通过RuntimeManager来完成一切，如下ProcessTest演示了如何使用JbpmJUnitBaseTestCase快速运行jBPM 6 Human tasks流程。ProcessTest内容如下所示：

package org.jbpm.demo.rewards;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.jbpm.test.JbpmJUnitBaseTestCase;
import org.junit.Test;
import org.kie.api.runtime.KieSession;
import org.kie.api.runtime.manager.RuntimeEngine;
import org.kie.api.runtime.manager.RuntimeManager;
import org.kie.api.task.TaskService;
import org.kie.api.task.model.TaskSummary;

public class ProcessTest extends JbpmJUnitBaseTestCase{

	public ProcessTest() {
		super(true, true);
	}
	
	@Test
	public void testRewardsProcess() {
		RuntimeManager manager = createRuntimeManager("org/jbpm/demo/rewards.bpmn");
		RuntimeEngine engine = manager.getRuntimeEngine(null);
		KieSession ksession = engine.getKieSession();
		TaskService taskService = engine.getTaskService();
		
		Map<String, Object> params = new HashMap<String, Object>();
        params.put("recipient", "kylin");
        ksession.startProcess("org.jbpm.demo.rewards", params);
        
		// let john execute Task 1
		List<TaskSummary> list = taskService.getTasksAssignedAsPotentialOwner("john", "en-UK");
		TaskSummary task = list.get(0);
		taskService.start(task.getId(), "john");
		taskService.complete(task.getId(), "john", null);

		// let mary execute Task 2
		list = taskService.getTasksAssignedAsPotentialOwner("mary", "en-UK");
		task = list.get(0);
		taskService.start(task.getId(), "mary");
		taskService.complete(task.getId(), "mary", null);

		manager.disposeRuntimeEngine(engine);
	}

}

ProcessTest 位于： https://github.com/kylinsoong/jbpm-6-examples/blob/master/rewards/src/main/java/org/jbpm/demo/rewards/ProcessTest.java

运行ProcessTest 同样输出：

process 1 started by kylin
john approved process 1
mary approved process 1
process 1 finished