spring aop，静态及动态代理例子

//依赖<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-aop</artifactId> </dependency>
@Aspect
@Component
public class LogUtil {

    @Pointcut("execution(public * com.ygsj.controller.*Controller.add*(..)) || execution(public * com.ygsj.controller.*Controller.update*(..)) || execution(public * com.ygsj.controller.*Controller.del*(..))" )
    public void point(){
    }

    @AfterReturning("point()")
    public void afterReturning(JoinPoint joinPoint){
        String className = joinPoint.getSignature().getDeclaringTypeName();
        String methodName = joinPoint.getSignature().getName();
        String str = methodName.substring(0,3);
        String content = "类"+className+"方法"+methodName+"的";
        String nowTime = new SimpleDateFormat("YYYY-MM-dd HH:mm:ss").format(new Date());
        switch (str){
            case "add":content += "添加操作";
                break;
            case "upd":content += "修改操作";
                break;
            case "del":content += "删除操作";
                break;
                default:
                    break;
        }
        System.out.println(content+"_________"+nowTime);
    }


    @AfterThrowing("point()")
    public void afterThrowing(){
        System.out.println("执行失败");
    }

    @Before("point()")
    public void before(){
        System.out.println("开始保存日志");
    }

    @After("point()")
    public void after(){
        System.out.println("保存日志执行完成");
    }
}

静态代理实现：接口实现

public interface JingtaiService {

    public void save();
    public void del();
}

public class JingtaiServiceImpl implements JingtaiService {
    @Override
    public void save() {
        System.out.print("保存数据");
    }

    @Override
    public void del() {
        System.out.print("删除数据");
    }
}


public class JingtaiProxy implements JingtaiService {

    @Autowired
    private JingtaiService target;

    public JingtaiProxy(JingtaiService target){
        this.target = target;
    }

    @Override
    public void save() {
        System.out.print("开始事物");
        target.save();
        System.out.print("结束事物");
    }
 @Override
    public void del() {
        System.out.print("开始事物");
        target.del();
        System.out.print("结束事物");
    }
}

 

测试：

    public static void main(String[] args) {
        JingtaiService jm = new JingtaiServiceImpl();
        JingtaiProxy jp = new JingtaiProxy(jm);
        jp.save(); 
}

 

动态代理：不需要接口实现，jdk方式实现

public class DongtaiProxy {

    private Object target;
    public DongtaiProxy(Object target) {
        this.target = target;
    }
    //ClassLoader loader,:指定当前目标对象使用类加载器,获取加载器的方法是固定的
    //Class<?>[] interfaces,:目标对象实现的接口的类型,使用泛型方式确认类型
    //InvocationHandler h:事件处理,执行目标对象的方法时,会触发事件处理器的方法,会把当前执行目标对象的方法作为参数传入
    public Object getProxy(){
        return Proxy.newProxyInstance(
                target.getClass().getClassLoader(),
                target.getClass().getInterfaces(),
                new InvocationHandler() {
                    @Override
                    public Object invoke(Object o, Method method, Object[] objects) throws Throwable {
                       System.out.print("开始动态事物");
                       Object returnvalue = method.invoke(target,objects);
                       System.out.print("提交事物");
                        return returnvalue;
                    }
                }
        );

    }

}

测试：

 public static void main(String[] args) {
        JingtaiService jm = new JingtaiServiceImpl();
        JingtaiService js = (JingtaiService)new DongtaiProxy(jm).getProxy();
        js.save();
        js.del();
    }