springboot+自定义注解+拦截器的写法

1、定义自定义注解的名称

/**
 * 在需要验证openid的Controller的方法上使用此注解
 */
@Target({ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
public @interface AccessRequired {
}

2、写自定义的拦截器，需继承HandlerInterceptor拦截器

public class AuthenticationInterceptor implements HandlerInterceptor {

   
    @Override
    public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object handler) throws Exception {
        if (!(handler instanceof HandlerMethod)) {
            return true;//没有实例化的方法直接通过
        }
        HandlerMethod handlerMethod = (HandlerMethod) handler;
        Method method = handlerMethod.getMethod();
 
        // 判断接口是否需要认证
        AccessRequired methodAnnotation = method.getAnnotation(AccessRequired.class);
        // 有 @AcessRequired注解，需要认证
        if (methodAnnotation != null) {
            String uuid = null;
            Cookie[] cookies = httpServletRequest.getCookies();
            if (!StringUtils.isEmpty(cookies) || cookies.length > 0) {

                for (int i = 0; i < cookies.length; i++) {
                    Cookie cookie = cookies[i];
                    if (cookie.getName().equals("openid")) {
                        uuid = cookie.getValue();
                    }
                }
            }

            if (StringUtils.isEmpty(uuid)) {
                httpServletResponse.setCharacterEncoding("UTF-8");
                httpServletResponse.setContentType("application/json; charset=utf-8");
                PrintWriter out = httpServletResponse.getWriter();
                String userJsonStr = ToolUtils.BeanToJson(ToolUtils.getRedirectUrl());

                out.print(userJsonStr);
                return false;
            } else {
                System.out.println(uuid);
                String openid = (String) redisService.get(uuid);
                System.out.println(openid);
                if (StringUtils.isEmpty(openid)) {
                    httpServletResponse.setCharacterEncoding("UTF-8");
                    httpServletResponse.setContentType("application/json; charset=utf-8");
                    PrintWriter out = httpServletResponse.getWriter();
                    String userJsonStr = ToolUtils.BeanToJson(ToolUtils.getRedirectUrl());
                    out.print(userJsonStr);
                    return false;
                } else {
                    httpServletRequest.setAttribute("openid", openid);
                    return true;
                }
            }

        }

        return true;
    }

    @Override
    public void postHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, ModelAndView modelAndView) throws Exception {

    }

    @Override
    public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) throws Exception {

    }

3、配置拦截器拦截哪些请求，注册拦截器

 * 注册拦截器
 */
@Configuration
public class WebAppConfig extends WebMvcConfigurerAdapter {
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        //注册自定义拦截器，添加拦截路径和排除拦截路径
        registry.addInterceptor(authenticationInterceptor()).addPathPatterns("/app/**","/sports/**");

        //.excludePathPatterns("api/path/login")

    }
    @Bean
    public AuthenticationInterceptor authenticationInterceptor() {
        return new AuthenticationInterceptor();
    }