如何描述Spring AOP的方面创建过程？

Question

Suppose I want to create an aspect which checks whether my repository method returns null or not:

@Aspect
public class NonNullReturningAspect
{

    @Around("anyPublicRepositoryMethod()  && args(pk,..  )")
    public Object checkNullResults(ProceedingJoinPoint joinPoint, Long pk) throws Throwable
    {    
        Object result = joinPoint.proceed();    
        if (result == null && hasNonNullReturningAnnotation(joinPoint))
        {
            Class<?> returnType = calculateReturnType(joinPoint);
            throw new ObjectNotFoundException(returnType, pk);
        }
        return result;
    }

    // ...

    @Pointcut(value = "execution(public * somepackage..repository..*.*(..))")
    private void anyPublicRepositoryMethod()
    {
    }

    @Pointcut("@annotation(NonNullReturning)")
    private void nonNullReturning()
    {
    }
}

This takes any method which has the @NonNullReturning annotation and automatically throws an exception if it wants to return with null .

What I want to achieve is to profile how much memory these aspects soak up and how much time Spring spends creating them?

The aspect works right now in a local scope but I should be able to tell how much resources will it take up when I start up Jetty (or Tomcat) with this aspect enabled application-wide.

Edit: I'm worried about the application startup time.

Answer 1

I have used following to see execution time of spring framework using aspectj.Just you need to download aspectjrt.jar and Configure and convert to aspectj project in ecclipse and you need source file of spring.

package org.springframework;

import java.util.ArrayList;
import java.util.List;

import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;

@Aspect
public class AspectJAnnotation {

    protected long starttime;
    protected long endtime;
    protected  ExecutionVaribale methodlevleinformation=new ExecutionVaribale();
    protected   List<ExecutionVaribale> liststore = new ArrayList<ExecutionVaribale>(); 







    @Before("execution(* *.*())") // this will call on before every method call on spring framework Or you can change it depending on which spring package method you can to monitor
    public void beforeAnymethodcall(final JoinPoint thisJoinPoint) {


        starttime = System.currentTimeMillis();
        methodlevleinformation.setMethodname(thisJoinPoint.getStaticPart().getSignature().getName());
    }

    @After("execution(* *.*())") // this will call on after every method call on spring framework Or you can change it depending on which spring package method you can to monitor
    public void afterAnymethodcall(final JoinPoint thisJoinPoint) {
        endtime = System.currentTimeMillis();

        methodlevleinformation.setDifferenetime((starttime - endtime)/ 1000); // time in secs
        liststore.add(methodlevleinformation);
        // at last you can iterate list and see the results .Hope this will provide a fine grain information on time taken by spring framework 




    }

     class ExecutionVaribale{


        /**
         * @return the differenetime
         */
        public long getDifferenetime() {
            return differenetime;
        }
        /**
         * @param differenetime the differenetime to set
         */
        public void setDifferenetime(long differenetime) {
            this.differenetime = differenetime;
        }
        /**
         * @return the methodname
         */
        public String getMethodname() {
            return methodname;
        }
        /**
         * @param methodname the methodname to set
         */
        public void setMethodname(String methodname) {
            this.methodname = methodname;
        }

        protected long differenetime;
        protected String  methodname;
    }


}

Answer to edit one :You need to see log how sequence of flow goes for bean creation ,that can be achieved by adding log4j.logger.org.springframework=ALL from there when server starts you can get little information on how the bean instantiation sequence goes on in container.Likewise you can customize bean creation. In log4j.properties put

log4j.rootLogger=INFO,stdout, file

log4j.appender.file=org.apache.log4j.RollingFileAppender

log4j.appender.file.layout=org.apache.log4j.PatternLayout

log4j.category.org.springframework=ALL

log4j.appender.file=org.apache.log4j.RollingFileAppender

log4j.appender.file.File=/folderUnderRootWhereApplicationServerResides/test.log

log4j.appender.file.Encoding=UTF-8

log4j.appender.file.MaxFileSize=40000000KB

log4j.appender.file.layout=org.apache.log4j.PatternLayout

log4j.appender.stdout=org.apache.log4j.ConsoleAppender

log4j.appender.stdout.layout=org.apache.log4j.PatternLayout

which package level you want to log org.springframework.aop is upper package and config is package under org.springframework.aop log4j.category.org.springframework.aop.config=DEBUG log4j.category.org.springframework.transaction=DEBUG

see log in test.log Or in eclipse console folderUnderRootWhereApplicationServerResides means if tomcat is installed in D then create folderUnderRootWhereApplicationServerResides folder in D drive

see http://www.mkyong.com/logging/log4j-log4j-properties-examples/