当注释具有参数时，Java EE CDI 拦截器不起作用

Question

我想写一个 CDI 拦截器。如果我的注释只包含 1 个参数，拦截效果很好，但如果使用 2 个参数，拦截就会中断。问题是为什么？

拦截器类:

@Monitored
@Interceptor
@Priority(APPLICATION)
public class MonitoringInterceptor {

    @AroundInvoke 
    public Object logInvocation(InvocationContext ctx) throws Exception {
        LOGGER.error("METHOD CALLED!!!"); //this is not called when annotation has 2 parameters
        return ctx.proceed();
    }
}

注释:

@InterceptorBinding
@Target({TYPE, METHOD})
@Retention(RUNTIME)
@Inherited
public @interface Monitored {
    public String layer() default "BUSINESS";
    public String useCase() default "N/A";
}

现在是有趣的部分:

@Stateless
public class MyBean {

    //this does not work, why?
    @Monitored(layer = "BUSINESS", useCase = "test")

    //if I use the following annotation it works well
    //@Monitored(layer = "BUSINESS")
    public String sayHello(String message) {
        return message; 
    }
}

我知道 MyBean 没有用 @Interceptors 注释。这是有意的。拦截器在 beans.xml 中声明:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://xmlns.jcp.org/xml/ns/javaee"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/beans_1_1.xsd"
   bean-discovery-mode="all">
<interceptors>
    <class>my.package.MonitoringInterceptor</class>
</interceptors>
</beans>

Answer 1

参数是绑定(bind)的一部分。用 @Nonbinding 注释参数，或者确保拦截器和拦截点使用相同的值。