如何检查Spring中的请求范围可用性？

Question

我正在尝试设置一些代码,如果spring的请求范围可用,它将以一种方式运行,如果所述范围不可用则采用另一种方式.

有问题的应用程序是一个Web应用程序,但有一些JMX触发器和计划任务(即Quartz)也会触发调用.

例如

/**
 * This class is a spring-managed singleton
 */
@Named
class MySingletonBean{

    /**
     * This bean is always request scoped
     */
    @Inject
    private MyRequestScopedBean myRequestScopedBean; 

    /* can be invoked either as part of request handling
       or as part of a JMX trigger or scheduled task */
    public void someMethod(){
        if(/* check to see if request scope is available */){
            myRequestScopedBean.invoke();
        }else{
            //do something else
        }
    }
}

假设myRequestScopedBean是请求作用域.

我知道这可以用try- catch围绕调用myRequestScopedBean,例如:

/**
 * This class is a spring-managed singleton
 */
@Named
class MySingletonBean{

    /**
     * This bean is always request scoped
     */
    @Inject
    private MyRequestScopedBean myRequestScopedBean; 

    /* can be invoked either as part of request handling
       or as part of a JMX trigger or scheduled task */
    public void someMethod(){
        try{
            myRequestScopedBean.invoke();
        }catch(Exception e){
            //do something else
        }
    }
}

但这看起来真的很笨重,所以我想知道是否有人知道一种优雅的Spring方式来询问某些东西,看看请求范围的bean是否可用.

非常感谢!

Answer 1

您可以使用此处描述的if检查

SPRING - 获取当前范围

if (RequestContextHolder.getRequestAttributes() != null) 
    // request thread

而不是捕捉异常.有时这看起来像最简单的解决方案.