Introducing Spring Framework

Chapter 8 ■ Give Advice to Your Spring Application
2014-02-23 20:29:30,241 DEBUG [main] @@@@(BEFORE) Method called: listAll
2014-02-23 20:29:30,241 DEBUG [main] @@@@(BEFORE) No arguments passed.
2014-02-23 20:29:30,241 DEBUG [main] @@@@(BEFORE) Method called: findByLocation
2014-02-23 20:29:30,241 DEBUG [main] @@@@(BEFORE) Argument passed:/some/path/
2014-02-23 20:29:30,241 ERROR [main] findByLocation not yet implemented.
It’s magic! Yes! You are now advising your code, removing the entire scattering and tangling of the logs. Your
SearchEngine implementation is now clean and you can just focus on your business logic.
After Advice
The after advice will be after the method call, and you can get a hold of the return value. This advice is done by
implementing the AfterReturningAdvice interface class. See Listing 8-8 for an example.
Listing 8-8. AfterLoggingModule.java
package com.apress.isf.spring.aop;
import java.lang.reflect.Method;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.aop.AfterReturningAdvice;
public class AfterLoggingModule implements AfterReturningAdvice {
private static final Logger log = LoggerFactory.getLogger(AfterLoggingModule.class);
}
public void afterReturning(Object returnValue, Method method,
Object[] args, Object target) throws Throwable {
if(log.isDebugEnabled()){
log.debug("@@@@(AFTER) Method called: " + method.getName());
if(args.length ==0 )
log.debug("@@@@(AFTER) No arguments passed.");
for(Object arg:args)
log.debug("@@@@(AFTER) Argument passed:" + arg);
log.debug("@@@(AFTER) Result: " + returnValue);
}
}
Listing 8-8 implements the method afterReturning that will have the returned value, the method that was
intercepted, the arguments of the method, and the object where the method was intercepted.
Now let’s modify your XML. Remember it will almost be the same as Listing 8-7, but now you are going to change
some ids, as shown in Listing 8-9.
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