use interceptor to log informations (J2EE 6 利用interceptor 打Log)

import javax.interceptor.AroundInvoke;

import javax.interceptor.Interceptor;

import javax.interceptor.InvocationContext;

Here is the example :

1.Define the annotation for interceptor

//@Inheritedto specify that the annotation can

//be inherited from superclasses

@Inherited

@InterceptorBinding

@Retention(RetentionPolicy.RUNTIME)

@Target({TYPE, METHOD})

public @interface Logged {

}

2. Define the interceptor

@Logged

@Interceptor

public class LoggedInterceptor implements Serializable {

private static final long serialVersionUID = 274175956305979479L;

public LoggedInterceptor() {

}

@AroundInvoke

public Object logMethodEntry(InvocationContext invocationContext)

throws Exception {

System.out.println("Entering method: "

+ invocationContext.getMethod().getName() + " in class "

+ invocationContext.getMethod().getDeclaringClass().getName()+"—start”);

Object o = invocationContext.proceed();

System.out.println("Entering method: "

+ invocationContext.getMethod().getName() + " in class "

+ invocationContext.getMethod().getDeclaringClass().getName()+"--end");

return o;

}

<class>com.interceptors.LoggedInterceptor</class>

</interceptors> add this in beans.xml to register the interceptor .

3. Use the inceptor : just put the annotation upon the method you want log something

@Logged

public String redirectUrlTest (){

return "detail.jsf";

}

here is the output

Entering method: redirectUrlTest in class com.test.render.TestMB--start

15:06:18,372 INFO [stdout] (http-localhost/127.0.0.1:8080-1) hi you are the best James ! Gentle

15:06:18,373 INFO [stdout] (http-localhost/127.0.0.1:8080-1) Entering method: redirectUrlTest in class com.test.render.TestMB--end