求解activiti工作流整合springmvc时ProcessEngines.getDefaultProcessEngine()为空的原因

[渝C8264]

applicationcontext代码如下：
<!-- 加载activiti引擎 -->
<bean id="processEngineConfiguration" class="org.activiti.spring.SpringProcessEngineConfiguration">
<property name="dataSource" ref="dataSource" />
<property name="transactionManager" ref="transactionManager" />
<property name="databaseSchemaUpdate" value="true" />
<property name="jobExecutorActivate" value="false" />
</bean>
<bean id="processEngine" class="org.activiti.spring.ProcessEngineFactoryBean">
<property name="processEngineConfiguration" ref="processEngineConfiguration" />
</bean>
<!-- activiti的各种服务接口 -->
<bean id="repositoryService" factory-bean="processEngine"
factory-method="getRepositoryService" />
<bean id="runtimeService" factory-bean="processEngine"
factory-method="getRuntimeService" />
<bean id="taskService" factory-bean="processEngine"
factory-method="getTaskService" />
<bean id="historyService" factory-bean="processEngine"
factory-method="getHistoryService" />
<bean id="managementService" factory-bean="processEngine"
factory-method="getManagementService" />
现在的情况是：首次运行能够自动创建相应的数据库表，但是运行
ProcessEngine processEngine = ProcessEngines.getDefaultProcessEngine();
System.out.println(processEngine);
RepositoryService reposit = processEngine.getRepositoryService();
DeploymentBuilder deploy = reposit.createDeployment();
会发现打印出来的对象是空，然后报错
Exception in thread "main" java.lang.NullPointerException
at com.ty.test.test.main(test.java:17)
求大神解救，分析下可能的原因有几种

[渝C8264]

没人吗？自己顶上去

[baidu_36530619]

帅哥，问题解决了吗？我也遇到这个问提了

[朝花夕拾y]

同问解决办法啊，在网上找了半天也没找到解决问题的办法

[xuludede]

用spring的注入， @Autowired private ProcessEngine processEngine; 然后直接调用processEngine即可