Spring系列篇--关于AOP【面向切面】的详解

package com.lya.aop.biz;
public interface IBookBiz {
    // 购书
    public boolean buy(String userName, String bookName, Double price);
    // 发表书评
    public void comment(String userName, String comments);
}

package com.lya.aop.biz.impl;
import com.YU.aop.biz.IBookBiz;
import com.YU.aop.exception.PriceException;
public class BookBizImpl implements IBookBiz {
    public BookBizImpl() {
        super();
    }
    public boolean buy(String userName, String bookName, Double price) {
        // 通过控制台的输出方式模拟购书
        if (null == price || price <= 0) {
            throw new PriceException("book price exception");
        }
        System.out.println(userName + " buy " + bookName + ", spend " + price);
        return true;
    }
    public void comment(String userName, String comments) {
        // 通过控制台的输出方式模拟发表书评
        System.out.println(userName + " say:" + comments);
    }
}

package com.lya.aop.advice;
import java.lang.reflect.Method;
import java.util.Arrays;
import org.springframework.aop.MethodBeforeAdvice;
/**
 * 买书、评论前加系统日志
 * @author YU
 *
 */
public class MyMethodBeforeAdvice implements MethodBeforeAdvice {
    @Override
    public void before(Method arg0, Object[] arg1, Object arg2) throws Throwable {
//        在这里，可以获取到目标类的全路径及方法及方法参数，然后就可以将他们写到日志表里去
        String target = arg2.getClass().getName();
        String methodName = arg0.getName();
        String args = Arrays.toString(arg1);
        System.out.println("【前置通知：系统日志】："+target+"."+methodName+"("+args+")被调用了");
    }
}

<!-- 代理-->
    <bean class="org.springframework.aop.framework.ProxyFactoryBean" id="bookProxy">
        <!-- 配置目标对象 -->
        <property name="target" ref="bookBiz"></property>
        <!-- 配置代理接口，目标对象的接口 -->
        <property name="proxyInterfaces">
            <value>com.YU.aop.biz.IBookBiz</value>
        </property>
        <property name="interceptorNames">
            <list>
                <value>myMethodBeforeAdvice</value>
            </list>
        </property>
    </bean>

package com.lya.util;
import com.lya.biz.IBookBiz;
import org.springframework.context.support.ClassPathXmlApplicationContext;
/**
 * @author 程序猿-小李哥
 * @site www.xiaolige.com
 * @company 猪八戒有限集团
 * @create 2023-08-17-15:34
 */
public class Demo {
    public static void main(String[] args) {
//        今天所学：
//        1.AOP的介绍：专心做事
//       2专业术语
//        1.连接点
//        2.通知：前，后，环绕
//        3.目标
//        4.代理
//        代理=目标+通知
//        3配置xml初始化Spring容器IOC
        ClassPathXmlApplicationContext context =
                new ClassPathXmlApplicationContext("spring.xml");
//        演示一：目标对象
//        BookBizImpl bookBiz = context.getBean("bookTarget",BookBizImpl.class);
//        bookBiz.buy("晓东","欠你一夜",2000d);
//        bookBiz.comment("晓东","不看亏了，看了真爽啊！");
//        演示二：前置通知
//        错误：类型强转，
        Object proxy1 = context.getBean("proxy");
        System.out.println(proxy1.getClass()+"代理的类型");
//      com.sun.proxy.$Proxy5代理的类型
//      这里proxy==new bookbizimpl
//        BookBizImpl proxy = context.getBean("proxy",BookBizImpl.class);
//        proxy.buy("晓东","欠你一夜",2000d);
//        proxy.comment("晓东","不看亏了，看了真爽啊！");
//        使用接口接收代理对象！！！因为代理对象实现了接口在xml中
        IBookBiz proxy = context.getBean("proxy",IBookBiz.class);
        proxy.buy("晓东","欠你一夜",2000d);
        proxy.comment("晓东","不看亏了，看了真爽啊！");
    }
}

package com.zking.aop.advice;
import java.lang.reflect.Method;
import java.util.Arrays;
import org.springframework.aop.AfterReturningAdvice;
/**
 * 买书返利
 * @author Administrator
 *
 */
public class MyAfterReturningAdvice implements AfterReturningAdvice {
    @Override
    public void afterReturning(Object arg0, Method arg1, Object[] arg2, Object arg3) throws Throwable {
        String target = arg3.getClass().getName();
        String methodName = arg1.getName();
        String args = Arrays.toString(arg2);
        System.out.println("【后置通知：买书返利】："+target+"."+methodName+"("+args+")被调用了，"+"该方法被调用后的返回值为："+arg0);
    }
}

package com.lya.advice;
import org.aopalliance.intercept.MethodInterceptor;
import org.aopalliance.intercept.MethodInvocation;
import java.util.Arrays;
/**
 * @author 程序猿-小李哥
 * @site www.xiaolige.com
 * @company 猪八戒有限集团
 * @create 2023-08-17-18:45
 *
 * 环绕通知
 */
public class AroundAdvice  implements MethodInterceptor {
    @Override
    public Object invoke(MethodInvocation invocation) throws Throwable {
        //获取目标对象的执行方法
        String methodName=invocation.getMethod().getName();
        //获取目标对象执行方法的参数
        Object[] params=invocation.getArguments();
        //获取目标对象
        Object target = invocation.getThis();
        System.out.println("[环绕通知] "+target.getClass().getName()+"."+methodName+","
                + "执行的参数："+ Arrays.toString(params));
        Object returnValue = invocation.proceed(); //放行操作
        System.out.println("[环绕通知] 返回参数等于："+returnValue);
        return returnValue;
    }
}

package com.lya.advice;
/**
 * @author 程序猿-小李哥
 * @site www.xiaolige.com
 * @company 猪八戒有限集团
 * @create 2023-08-17-18:56
 */
import org.springframework.aop.ThrowsAdvice;
/**
 * 异常通知
 */
public class ExceptionAdvice implements ThrowsAdvice {
        public void afterThrowing(PriceException e) {
        System.out.println("[异常通知] 价格异常，撤销订单！");
    }
}

package com.lya.advice;
/**
 * @author 程序猿-小李哥
 * @site www.xiaolige.com
 * @company 猪八戒有限集团
 * @create 2023-08-17-19:04
 *
 * 价格异常通知
 */
public class PriceException  extends RuntimeException {
    public PriceException() {
        super();
    }
    public PriceException(String message, Throwable cause, boolean enableSuppression, boolean writableStackTrace) {
        super(message, cause, enableSuppression, writableStackTrace);
    }
    public PriceException(String message, Throwable cause) {
        super(message, cause);
    }
    public PriceException(String message) {
        super(message);
    }
    public PriceException(Throwable cause) {
        super(cause);
    }
}