package org.example.annotation;
import java.lang.annotation.*;
@Target({ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface DemoAnnotation {
String value() default "test";
}
package org.example.config;
import lombok.extern.slf4j.Slf4j;
import org.example.interceptor.DemoInterceptor;
import org.springframework.aop.aspectj.AspectJExpressionPointcut;
import org.springframework.aop.support.DefaultPointcutAdvisor;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
@Configuration
@ConditionalOnProperty(name = "aop.exception.pointcut", matchIfMissing = true)
@Slf4j
public class AopConfig {
/**
* 异常的切面
*
* @return
*/
@Bean
public DefaultPointcutAdvisor defaultPointcutAdvisor2() {
// 声明切点
//JdkRegexpMethodPointcut pointcut = new JdkRegexpMethodPointcut();
//pointcut.setPatterns("com.example.*");
AspectJExpressionPointcut pointcut = new AspectJExpressionPointcut();
pointcut.setExpression("@annotation(org.example.annotation.DemoAnnotation)"); // 拦截org.example.service包和子包下带一个参数的任何方法
// 声明增强
DemoInterceptor interceptor = new DemoInterceptor();
// 配置切面
DefaultPointcutAdvisor advisor = new DefaultPointcutAdvisor();
advisor.setPointcut(pointcut);
advisor.setAdvice(interceptor);
return advisor;
}
}
package org.example.service.impl;
import org.example.annotation.DemoAnnotation;
import org.example.entity.User;
import org.example.mapper.UserMapper;
import org.example.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
@Service
public class UserServiceImpl implements UserService {
@Autowired
private UserMapper userMapper;
@Override
@Transactional
@DemoAnnotation("insert")
public void insert(User user) {
userMapper.insert(user);
}
@Override
public User findById(Long id) {
return userMapper.selectById(id);
}
}
package org.example.interceptor;
import cn.hutool.json.JSONUtil;
import org.aopalliance.intercept.MethodInterceptor;
import org.aopalliance.intercept.MethodInvocation;
import org.example.annotation.DemoAnnotation;
import java.lang.reflect.Method;
public class DemoInterceptor implements MethodInterceptor {
@Override
public Object invoke(MethodInvocation methodInvocation) throws Throwable {
System.out.println("--------------------------------------------------");
// 参数
Object[] object = methodInvocation.getArguments();
for (Object obj : object) {
System.out.println(JSONUtil.toJsonStr(obj));
}
// 对象
Object obj = methodInvocation.getThis();
System.out.println(obj.getClass().getName());
// 方法
Method method = methodInvocation.getMethod();
System.out.println(method.getName());
// 继续执行，obj是方法执行结果，有可能是void方法，此时obj == null
obj = methodInvocation.proceed();
if (obj != null){
System.out.println(obj.getClass().getName());
}
// 获取注解
DemoAnnotation d = method.getAnnotation(DemoAnnotation.class);
if (d == null) {
System.out.println("当前类没有DemoAnnotation注解");
} else {
System.out.println(d.value());
}
System.out.println("--------------------------------------------------");
return obj;
}
}
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