Datasheet

Figure 1-4

Adding a Logging Aspect

In this section, you can try out Spring AOP support by applying a logging aspect to the existing calcula-

tion code.

The code for the logging aspect is the

com.wrox.begspring,aspects.LoggingAspect class, which

you can find under the

src\chapter1\springaop\src\main\java\com\wrox\begspring\aspects

directory; it is shown here:

package com.wrox.begspring.aspects;

import org.aspectj.lang.JoinPoint;

import org.aspectj.lang.annotation.Aspect;

import org.aspectj.lang.annotation.Before;

@Aspect

public class LoggingAspect {

@Before(“execution(* com.wrox.begspring.Operation.*(..))”)

public void logMethodExecution(JoinPoint jp) {

System.out.println(“AOP logging -> “

+ jp.toShortString() );

}

The logging aspect that can be applied is in boldface in the preceding code. Note that there is nothing

about this aspect code that refers to the

CalculateSpring code — the target to which it is applied. In

fact, this aspect can be coded, modified, and maintained independently of the

CalculateSpring code.

Existing target code modules

SPRING AOP

Matches pointouts and apply aspects

Logging aspect (code)

Apply

aspect

here

Apply

aspect

here

Apply

aspect

here

Matched

JoinPoint

Matched

JoinPoint

Matched

JoinPoint

Chapter 1: Jump Start Spring 2

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