Spring 切面执行链的实现示例

// UserService.java
@Service
public class UserService {

  private final Logger logger = Logger.getLogger(UserService.class.getName());

  @ToLog
  public String getUser(String username) throws Exception {
    logger.info("getUser method called with username: " + username);
    return username;
  }
}

// LoggingAspect.java
// 定义日志切面
@Aspect
public class LoggingAspect {

  // 定义日志记录器
  private final Logger logger = Logger.getLogger(LoggingAspect.class.getName());

  // 定义日志环绕通知
  @Around("@annotation(dev.xyz.annotation.ToLog)")
  public Object logAround(ProceedingJoinPoint joinPoint) throws Throwable {
    // 切入点方法执行前执行
    logger.info("Logging before method: " + joinPoint.getSignature().getName());
    // 执行切入点方法
    Object result = joinPoint.proceed();
    // 切入点方法执行后执行
    logger.info("Logging after method: " + joinPoint.getSignature().getName());
    // 修改切入点方法的返回值
    return result;
  }
}

// SecurityAspect.java
// 定义鉴权切面
@Aspect
public class SecurityAspect {

  private final Logger logger = Logger.getLogger(SecurityAspect.class.getName());

  @Around("@annotation(dev.xyz.annotation.ToLog)")
  public Object checkSecurity(ProceedingJoinPoint joinPoint) throws Throwable {
    logger.info("Security check performed.");
    // 这里模拟鉴权失败
    if (joinPoint.getArgs()[0].equals("Mark")) {
      throw new Exception("Security check failed.");
    }
    Object result = joinPoint.proceed();
    logger.info("Security check passed.");
    return result;
  }
}

// ProjectConfig.java
// Spring 配置，创建两个切面 bean
@Configuration
@ComponentScan(basePackages = "dev.xyz.service")
@EnableAspectJAutoProxy
public class ProjectConfig {

  @Bean
  SecurityAspect securityAspect() {
    return new SecurityAspect();
  }

  @Bean
  LoggingAspect loggingAspect() {
    return new LoggingAspect();
  }
}

// Main.java
// 在 main 方法中进行测试
public class Main {
    public static void main(String[] args) throws Exception {

        AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(ProjectConfig.class);

        UserService userService = context.getBean(UserService.class);
        userService.getUser("Mark");
    }
}

// LoggingAspect.java
// 定义日志切面
@Aspect
@Order(1)
public class LoggingAspect {

	// 这里的代码不变
  // ...
}

// SecurityAspect.java
// 定义鉴权切面
@Aspect
public class SecurityAspect {

	// 这里的代码不变
  // ...
}