测定接口执行效率
描述:在接口执行前输出当前系统时间
开发模式:XML or 注解
思路分析:
1.导入坐标(pom.xml)
<dependencies>
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
            <version>1.9.4</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>5.2.25.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>3.8.1</version>
            <scope>test</scope>
        </dependency>
    </dependencies>
        2.制作连接点的方法(原始操作)
package org.example.dao;
public interface BookDao {
    void save();
    void update();
}
package org.example.dao.impl;
import org.example.dao.BookDao;
import org.springframework.stereotype.Repository;
@Repository
public class BookDaoImpl implements BookDao {
    public void save() {
        System.out.println("book dao save");
        System.out.println(System.currentTimeMillis());
    }
    public void update() {
        System.out.println("book dao update");
    }
    public void delete() {
        System.out.println("book dao delete");
    }
    public void select() {
        System.out.println("book dao select");
    }
}
        4.定义切入点
package org.example.aop;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.springframework.stereotype.Component;
@Component
@Aspect//当作Aop处理
public class MyAdvice {
    @Pointcut("execution(void org.example.dao.BookDao.update())")
    private void pt(){}
    @Before("pt()")
    public void method(){
        System.out.println(System.currentTimeMillis());
    }
}
        5.注解驱动支持
package org.example.config;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.EnableAspectJAutoProxy;
@Configuration
@ComponentScan("org.example")
@EnableAspectJAutoProxy//有用注解开发的AOP
public class SpringConfig {
}
        测试
package org.example;
import org.example.config.SpringConfig;
import org.example.dao.BookDao;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
/**
 * Hello world!
 *
 */
public class App 
{
    public static void main( String[] args )
    {
        ApplicationContext ctx=new AnnotationConfigApplicationContext(SpringConfig.class);
        BookDao bookDao=ctx.getBean(BookDao.class);
        bookDao.save();
        bookDao.update();
    }
}