I am new to spring in my office . So there is no guidance for me.
I need to implement the logging with the AOP
using the log4j
.
I have implemented the logging without AOP
in basic spring MVC
example ?
Also did the small sample in AOP
using the aspectJ
without logging (just made the Sysout
) ?
I don't know how to integrate it ?
Can any one please give me a start up idea?
Good answers are definitely appreciated ...
Spring makes it really easy for us to make use of AOP. Here's a simple logging example:
@Aspect
public class MyLogger {
private Logger log = Logger.getLogger(getClass());
@After("execution(* com.example.web.HomeController.*(..))")
public void log(JoinPoint point) {
log.info(point.getSignature().getName() + " called...");
}
}
Then simply configure your applicationContext.xml (or equivalent):
<aop:aspectj-autoproxy>
<aop:include name="myLogger"/>
</aop:aspectj-autoproxy>
<bean id="myLogger" class="com.example.aspect.MyLogger"/>
You'll notice in the MyLogger class that I specified @After
right above the method. This is called the advice and it basically specifies that this 'log' method will be called after the method in question. Other options include @Before, @Around, @AfterThrowing
.
The expression "execution(* com.example.web.HomeController.*(..))"
is called a pointcut expression and specifies what we're targeting (in this case all methods of the HomeController class).
P.S. The aop
namespace (xmlns:aop="http://www.springframework.org/schema/aop"
) and the schema location (version dependent) would need to be added to your applicationContext.xml right at the top. Here is my setup:
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.1.xsd
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.1.xsd">