Activiti监听器中如何利用各种服务或者自己写的Service
1、首先
首先利用spring的依赖注入是没有问题的，自己写的service也一样，可是到运行的时候，就会出现这种状况。
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.yl.event.TaskInfoHandler#402e2375': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: org.activiti.engine.TaskService org.yl.event.TaskInfoHandler.taskService; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'processEngine': FactoryBean threw exception on object creation; nested exception is java.lang.RuntimeException: java.lang.NullPointerException
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:334)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1202)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveInnerBean(BeanDefinitionValueResolver.java:299)
... 46 more
Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: org.activiti.engine.TaskService org.yl.event.TaskInfoHandler.taskService; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'processEngine': FactoryBean threw exception on object creation; nested exception is java.lang.RuntimeException: java.lang.NullPointerException
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:561)
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:331)
... 50 more
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'processEngine': FactoryBean threw exception on object creation; nested exception is java.lang.RuntimeException: java.lang.NullPointerException
at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:175)
at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.getObjectFromFactoryBean(FactoryBeanRegistrySupport.java:103)
at org.springframework.beans.factory.support.AbstractBeanFactory.getObjectForBeanInstance(AbstractBeanFactory.java:1517)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:314)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:368)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1111)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1006)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:504)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1120)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1044)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:942)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:533)
... 52 more
Caused by: java.lang.RuntimeException: java.lang.NullPointerException
at org.openwebflow.cfg.ProcessEngineConfigurationEx.buildProcessEngine(ProcessEngineConfigurationEx.java:36)
at org.activiti.spring.ProcessEngineFactoryBean.getObject(ProcessEngineFactoryBean.java:60)
at org.activiti.spring.ProcessEngineFactoryBean.getObject(ProcessEngineFactoryBean.java:32)
at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:168)
... 69 more
Caused by: java.lang.NullPointerException
at org.openwebflow.cfg.ProcessEngineConfigurationEx.buildProcessEngine(ProcessEngineConfigurationEx.java:24)
... 72 more
不截图了·，怕你们又要说我，截图看不清楚
其实我一直认为在监听器添加注入service是不行的，但是今天遇到一位大神，我的理论被推翻了。
步骤如下。
1、首先放入一个工具类在你的项目中
package com.xbj.common.utils;
import org.apache.commons.lang3.Validate;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.DisposableBean;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
public class SpringContextHolder implements ApplicationContextAware, DisposableBean {
private static ApplicationContext applicationContext = null;
private static Logger logger = LoggerFactory.getLogger(SpringContextHolder.class);
/**
* 取得存储在静态变量中的ApplicationContext.
*/
public static ApplicationContext getApplicationContext() {
assertContextInjected();
return applicationContext;
}
/**
* 从静态变量applicationContext中取得Bean, 自动转型为所赋值对象的类型.
*/
@SuppressWarnings("unchecked")
public static <T> T getBean(String name) {
assertContextInjected();
return (T) applicationContext.getBean(name);
}
/**
* 从静态变量applicationContext中取得Bean, 自动转型为所赋值对象的类型.
*/
public static <T> T getBean(Class<T> requiredType) {
assertContextInjected();
return applicationContext.getBean(requiredType);
}
/**
* 清除SpringContextHolder中的ApplicationContext为Null.
*/
public static void clearHolder() {
logger.debug("清除SpringContextHolder中的ApplicationContext:"
+ applicationContext);
applicationContext = null;
}
/**
* 实现ApplicationContextAware接口, 注入Context到静态变量中.
*/
@Override
public void setApplicationContext(ApplicationContext applicationContext) {
// logger.debug("注入ApplicationContext到SpringContextHolder:{}", applicationContext);
if (SpringContextHolder.applicationContext != null) {
logger.warn("SpringContextHolder中的ApplicationContext被覆盖, 原有ApplicationContext为:" + SpringContextHolder.applicationContext);
}
SpringContextHolder.applicationContext = applicationContext; // NOSONAR
}
/**
* 实现DisposableBean接口, 在Context关闭时清理静态变量.
*/
@Override
public void destroy() throws Exception {
SpringContextHolder.clearHolder();
}
/**
* 检查ApplicationContext不为空.
*/
private static void assertContextInjected() {
Validate.validState(applicationContext != null, "applicaitonContext属性未注入, 请在applicationContext.xml中定义SpringContextHolder.");
}
}
这上面的包名自己改下
2、在spring.xml中配置下这个，没有顺序，放到哪里都可以
<bean id="springContextHolder" class="com.xbj.common.utils.SpringContextHolder" lazy-init="false"/>
路径自己也要改下啊
3、
然后在监听器中初始化你想要的Service
runtimeService = SpringContextHolder.getBean(RuntimeService.class);
比如上面这样的service，就能够获取到Service
4
最后能够使用service
转载于:https://my.oschina.net/mdxlcj/blog/967699