activiti监听生命周期

activiti生命周期的作用

生命周期的作用是在构建processEngine实例时候或者关闭的时候调用对应处理方法,比如我在启动实例的时候，可以对实例做一些预处理

activiti的接口类

public interface ProcessEngineLifecycleListener { /**实体引擎实例化的时候调用该方法*/ void onProcessEngineBuilt(ProcessEngine processEngine); /**实体引擎关闭的时候调用该方法*/ void onProcessEngineClosed(ProcessEngine processEngine); }

activiti的生命周期的实现

       首先通过bean进行实例化，再注入到当前bean，具体监听则是在构建实例和关闭实例的时候

   构建实例：会调用监听类的onProcessEngineBuilt方法

/** * @author 郑小康 * * 1.注入流程配置实例的一些变量到当前实例 * * 2.FIXME:未知 * * 3.注册当前流程实例 * * 4.FIXME:未知 * * 5.调用监听方法，这也是这里需要描述的核心（不是本方法的核心） * */ public ProcessEngineImpl(ProcessEngineConfigurationImpl processEngineConfiguration) { this.processEngineConfiguration = processEngineConfiguration; this.name = processEngineConfiguration.getProcessEngineName(); this.repositoryService = processEngineConfiguration.getRepositoryService(); this.runtimeService = processEngineConfiguration.getRuntimeService(); this.historicDataService = processEngineConfiguration.getHistoryService(); this.identityService = processEngineConfiguration.getIdentityService(); this.taskService = processEngineConfiguration.getTaskService(); this.formService = processEngineConfiguration.getFormService(); this.managementService = processEngineConfiguration.getManagementService(); this.dynamicBpmnService = processEngineConfiguration.getDynamicBpmnService(); this.asyncExecutor = processEngineConfiguration.getAsyncExecutor(); this.commandExecutor = processEngineConfiguration.getCommandExecutor(); this.sessionFactories = processEngineConfiguration.getSessionFactories(); this.transactionContextFactory = processEngineConfiguration.getTransactionContextFactory(); this.formEngineRepositoryService = processEngineConfiguration.getFormEngineRepositoryService(); this.formEngineFormService = processEngineConfiguration.getFormEngineFormService(); if (processEngineConfiguration.isUsingRelationalDatabase() && processEngineConfiguration.getDatabaseSchemaUpdate() != null) { commandExecutor.execute(processEngineConfiguration.getSchemaCommandConfig(), new SchemaOperationsProcessEngineBuild()); } if (name == null) { log.info("default activiti ProcessEngine created"); } else { log.info("ProcessEngine {} created", name); } ProcessEngines.registerProcessEngine(this); if (asyncExecutor != null && asyncExecutor.isAutoActivate()) { asyncExecutor.start(); } //流程引擎实例化监听方法 if (processEngineConfiguration.getProcessEngineLifecycleListener() != null) { processEngineConfiguration.getProcessEngineLifecycleListener().onProcessEngineBuilt(this); } processEngineConfiguration.getEventDispatcher().dispatchEvent(ActivitiEventBuilder.createGlobalEvent(ActivitiEventType.ENGINE_CREATED)); }    关闭实例会调用onProcessEngineClosed方法

public void close() { ProcessEngines.unregister(this); if (asyncExecutor != null && asyncExecutor.isActive()) { asyncExecutor.shutdown(); } commandExecutor.execute(processEngineConfiguration.getSchemaCommandConfig(), new SchemaOperationProcessEngineClose()); //流程引擎关闭触发监听方法 if (processEngineConfiguration.getProcessEngineLifecycleListener() != null) { processEngineConfiguration.getProcessEngineLifecycleListener().onProcessEngineClosed(this); } processEngineConfiguration.getEventDispatcher().dispatchEvent(ActivitiEventBuilder.createGlobalEvent(ActivitiEventType.ENGINE_CLOSED)); }

activiti生命周期的使用

上面是生命周期的源码实现介绍,下面就讲述一下怎样使用

第一步：实现ProcessEngineLifecycleListener这个接口

public class processEngineLifecycleListener implements ProcessEngineLifecycleListener{ public void onProcessEngineBuilt(ProcessEngine processEngine) { System.out.println("流程引擎生命周期监听器开始了...."); ProcessEngineConfiguration pec = processEngine.getProcessEngineConfiguration(); String activityFontName = pec.getActivityFontName(); System.out.println(activityFontName); } public void onProcessEngineClosed(ProcessEngine processEngine) { } }

第二步：配置当前processEngineLifecycleListener这个bean并将其注入processEngineConfiguration里面

<beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd"> <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource"> <property name="driverClassName"> <value>com.mysql.jdbc.Driver</value> </property> <property name="url"> <value>jdbc:mysql://127.0.0.1:3306/activiti?useUnicode=true&characterEncoding=UTF-8 </value> </property> <property name="username"> <value>root</value> </property> <property name="password" value="fadp" /> </bean> <bean id="processEngineLifecycleListener" class="com.activiti_study.ch6.processEngineLifecycleListener"></bean> <bean id="processEngine1" name="processEngineConfiguration" class="org.activiti.engine.impl.cfg.StandaloneProcessEngineConfiguration"> <property name="dataSource" ref="dataSource" /> <property name="databaseSchemaUpdate" value="true" /> <property name="processEngineLifecycleListener" ref="processEngineLifecycleListener"></property> </bean> </beans>

第三步：具体实现

      

@Test public void getDefaultProcessEngine() throws FileNotFoundException { ProcessEngineConfiguration processEngineConfiguration = ProcessEngineConfiguration.createProcessEngineConfigurationFromResource("com/activiti_study/ch6/activiti1.cfg.xml","processEngineConfiguration"); ProcessEngine pe = processEngineConfiguration.buildProcessEngine(); System.out.println(pe+"========"); }

流程引擎生命周期监听器开始了.... Arial org.activiti.engine.impl.ProcessEngineImpl@4b29d1d2========

      从显示结果可以看出在调用buildProcessEngine方法的时候调用了ProcessEngineLifecycleListener继承类的onProcessEngineBuilt方法