jBPM(三)：Spring 集成 jBPM4.3 （jBPM4+Hibernate4）

Spring 集成 jBPM4.3 主要工作有2点：

1. 将jbpm默认的hibernate事务换成spring事务，即在jbpm.cfg.xml文件中将

<import resource="jbpm.tx.hibernate.cfg.xml" />

替换成：

 <import resource="jbpm.tx.spring.cfg.xml" />

2. jBPM的核心控件processEngine由Spring生成、管理。

这2方面的内容，网上有很多资料查询，但基本都是在xml文件中进行配置，而我是在之前的代码中集成jBPM，之前的代码采用的是注解的方式（Spring注解，Hibernate注解），所以采用编码的方式获得了processEngine对象，即：

	@Bean(name="processEngine") 
	@DependsOn("sessionFactory")
	public ProcessEngine getProcessEngine() throws Exception{ 
		processEngine = new ConfigurationImpl().springEnabled()
               .setHibernateSessionFactory(this.getSessionFactory())
               .springInitiated(applicationContext)
               .buildProcessEngine(); 
		return processEngine;
	} 

从上述代码中可以看到，生成processEngine对象需要设置SessionFactory对象。查看jBPM4.3源码SpringProcessEngine.java类，发现其获取的是LocalSessionFactoryBena对象，而我在代码中采用的是注解方式，所以生成的是AnnotationSessionFactoryBean对象，即：

	@Bean(name="annotationSessionFactoryBean")
	@DependsOn("dataSource")
	public AnnotationSessionFactoryBean getAnnotationSessionFactoryBean() throws Exception { 
		
		Properties properties = new Properties();
		properties.put("hibernate.dialect", dialect); 
		properties.put("hibernate.show_sql", showSql);
		properties.put("hibernate.hbm2ddl.auto", hbm2ddl);
		properties.put("hibernate.max_fetch_depth", max_fetch_depth);
		properties.put("hibernate.temp.use_jdbc_metadata_defaults", "false");  
		properties.put("hibernate.jdbc.fetch_size", "50");
		properties.put("hibernate.jdbc.batch_size", "25"); 
		 
		AnnotationSessionFactoryBean a = new AnnotationSessionFactoryBean(); 
		a.setDataSource(this.getDataSource());
		a.setHibernateProperties(properties);   
		a.setPackagesToScan(models.split(","));
		// jbpm文件
		a.setMappingResources(new String[]{"jbpm.repository.hbm.xml","jbpm.execution.hbm.xml","jbpm.history.hbm.xml","jbpm.task.hbm.xml","jbpm.identity.hbm.xml"});  
		a.afterPropertiesSet();   
		return a;
		
	} 

解决的办法是在本地源码中新建一个对应的SpringProcessEngine类，用以覆盖jBPM源码。修改其中的代码，获取AnnotationSessionFactoryBean对象。以下是修改的create方法：

  public static ProcessEngine create(ConfigurationImpl configuration) {
    SpringProcessEngine springProcessEngine = null;
    
    ApplicationContext applicationContext = null;
    if (configuration.isInstantiatedFromSpring()) {
      applicationContext = (ApplicationContext) configuration.getApplicationContext();

      springProcessEngine = new SpringProcessEngine();
      springProcessEngine.applicationContext = applicationContext;
      springProcessEngine.initializeProcessEngine(configuration);

//      原先的代码
//      LocalSessionFactoryBean localSessionFactoryBean = springProcessEngine.get(LocalSessionFactoryBean.class);
//      Configuration hibernateConfiguration = localSessionFactoryBean.getConfiguration();
//      springProcessEngine.processEngineWireContext
//          .getWireDefinition()
//          .addDescriptor(new ProvidedObjectDescriptor(hibernateConfiguration, true));
//      
//      springProcessEngine.checkDb(configuration);
      
      // 将LocalSessionFactoryBean 换成 AnnotationSessionFactoryBean
      
      AnnotationSessionFactoryBean annotationSessionFactoryBean = springProcessEngine.get(AnnotationSessionFactoryBean.class);
      Configuration hibernateConfiguration = annotationSessionFactoryBean.getConfiguration();       
      springProcessEngine.processEngineWireContext
                         .getWireDefinition()
                         .addDescriptor(new ProvidedObjectDescriptor(hibernateConfiguration, true));
      
      springProcessEngine.checkDb(configuration); 

    } else {
      String springCfg = (String) configuration.getProcessEngineWireContext().get("spring.cfg");
      if (springCfg==null) {
        springCfg = "applicationContext.xml";
      }
      applicationContext = new ClassPathXmlApplicationContext(springCfg);
      springProcessEngine = (SpringProcessEngine) applicationContext.getBean("processEngine");
    }
    
    return springProcessEngine;
  }

本地新建的类：