publicinterfaceHandlerInterceptor{
// 1. 請求進(jìn)入Controller之前執(zhí)行（鑒權(quán)寫這里）
defaultbooleanpreHandle(HttpServletRequest request,HttpServletResponse response,Object handler)throwsException{
returntrue;// true=放行 false=攔截
}
// 2. Controller執(zhí)行完畢，渲染頁面之前執(zhí)行
defaultvoidpostHandle(...)throwsException{}
// 3. 整個請求完全結(jié)束后執(zhí)行（清理資源）
defaultvoidafterCompletion(...)throwsException{}
}

importlombok.extern.slf4j.Slf4j;
importorg.springframework.web.servlet.HandlerInterceptor;
importjavax.servlet.http.HttpServletRequest;
importjavax.servlet.http.HttpServletResponse;
/**
* 登錄攔截器：校驗是否登錄
*/
@Slf4j
publicclassLoginInterceptorimplementsHandlerInterceptor{
// 進(jìn)入Controller前執(zhí)行：核心校驗邏輯
@Override
publicbooleanpreHandle(HttpServletRequest request,HttpServletResponse response,Object handler)throwsException{
// 1. 獲取前端傳遞的 Token / Session
String token = request.getHeader("token");
        log.info("當(dāng)前請求token：{}", token);
// 2. 判斷是否登錄（真實項目：查詢Redis/數(shù)據(jù)庫）
if(token ==null|| token.isEmpty()){
            log.error("用戶未登錄，請求被攔截");
// 攔截，返回未登錄提示
            response.setContentType("application/json;charset=utf-8");
            response.getWriter().write("{\"code\":401,\"msg\":\"未登錄，請先登錄\",\"data\":null}");
returnfalse;
}
// 3. 登錄有效，放行
returntrue;
}
}

importorg.springframework.context.annotation.Configuration;
importorg.springframework.web.servlet.config.annotation.InterceptorRegistry;
importorg.springframework.web.servlet.config.annotation.WebMvcConfigurer;
/**
*Web 配置：注冊攔截器
*/
@Configuration
publicclassWebConfigimplementsWebMvcConfigurer{
@Override
publicvoidaddInterceptors(InterceptorRegistry registry){
        registry.addInterceptor(newLoginInterceptor())
.addPathPatterns("/**")// 攔截所有請求
.excludePathPatterns(// 放行白名單
"/user/login",// 登錄接口
"/user/register",// 注冊接口
"/swagger/**",// 接口文檔
"/v3/api-docs/**"
);
}
}

response.setContentType("application/json;charset=utf-8");
Result result =Result.fail(401,"未登錄，請先登錄");
response.getWriter().write(newObjectMapper().writeValueAsString(result));
returnfalse;

{
"code":401,
"msg":"未登錄，請先登錄",
"data":null
}

1@Slf4j
2publicclassLoginInterceptorimplementsHandlerInterceptor{
3
4@Autowired
5privateRedisTemplate<String,Object> redisTemplate;
6
7@Override
8publicbooleanpreHandle(HttpServletRequest request,HttpServletResponse response,Object handler)throwsException{
9String token = request.getHeader("token");
10
11// 1. 無token
12if(token ==null|| token.isBlank()){
13returnresponseFail(response,"未登錄，請先登錄");
14}
15
16// 2. 校驗Redis
17Object user = redisTemplate.opsForValue().get("login:token:"+ token);
18if(user ==null){
19returnresponseFail(response,"登錄已過期，請重新登錄");
20}
21
22// 3. 放行
23returntrue;
24}
25
26// 統(tǒng)一返回錯誤
27privatebooleanresponseFail(HttpServletResponse response,String msg)throwsException{
28        response.setContentType("application/json;charset=utf-8");
29Result<?> result =Result.fail(401, msg);
30        response.getWriter().write(newObjectMapper().writeValueAsString(result));
31returnfalse;
32}
33}

HandlerMethod handlerMethod =(HandlerMethod) handler;
String methodName = handlerMethod.getMethod().getName();
String className = handlerMethod.getBean().getClass().getName();

.excludePathPatterns("/static/**","/img/**","/css/**","/js/**")

registry.addInterceptor(A).order(1);
registry.addInterceptor(B).order(2);