SpringBoot快速设置拦截器并实现权限验证的方法

public abstract class HandlerInterceptorAdapter implements AsyncHandlerInterceptor {

  // 在目标方法执行前执行
  @Override
  public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
    return true;
  }

  // 在目标方法执行后执行，但在请求返回前，我们仍然可以对 ModelAndView进行修改
  @Override
  public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) 
             throws Exception {}

  // 在请求已经返回之后执行
  @Override
  public void afterCompletion(
      HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
      throws Exception {}

  // 用来处理异步请求, 当Controller中有异步请求方法的时候会触发该方法
  @Override
  public void afterConcurrentHandlingStarted(
      HttpServletRequest request, HttpServletResponse response, Object handler)
      throws Exception {}
}

@Inherited
@Target({ElementType.TYPE, ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface Auth {
  String user() default "";
}

@RestController
@EnableAutoConfiguration
public class DemoController {

  @Auth(user = "admin")
  @RequestMapping(value = "/hello", method = RequestMethod.GET)
  public String sayHello() {
    return "hello world.";
  }
}

  @Override
  public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
    System.out.println("preHandle");
    if (!handler.getClass().isAssignableFrom(HandlerMethod.class)) {
      System.out.println("cat cast handler to HandlerMethod.class");
      return true;
    }
    // 获取注解
    Auth auth = ((HandlerMethod) handler).getMethod().getAnnotation(Auth.class);
    if (auth == null) {
      System.out.println("cant find @Auth in this uri:" + request.getRequestURI());
      return true;
    }
    // 从参数中取出用户身份并验证
    String admin = auth.user();
    if (!admin.equals(request.getParameter("user"))) {
      System.out.println("permission denied");
      response.setStatus(403);
      return false;
    }
    return true;
  }

@Configuration
public class ConfigAdapter extends WebMvcConfigurerAdapter {
  @Override
  public void addInterceptors(InterceptorRegistry registry) {
    registry.addInterceptor(new LoginInterceptor()).addPathPatterns("/hello");
  }
}