Java自定义注解校验token并直接返回给前端状态

自定义注解 CheckToken 

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
public @interface CheckToken {
}

编写验证token的方法TokenInterceptor 

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;public class TokenInterceptor extends HandlerInterceptorAdapter {@Overridepublic boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {if (handler instanceof HandlerMethod) {HandlerMethod handlerMethod = (HandlerMethod) handler;// 检查方法是否有自定义注解if (handlerMethod.getMethodAnnotation(CheckToken.class) != null) {// 获取请求中的tokenString token = request.getHeader("token");// TODO 这里添加你的逻辑来验证token的合法性boolean validateToken = validateToken(token)if (!validateToken) {// 如果token无效，直接返回错误响应给前端response.setStatus(HttpServletResponse.SC_UNAUTHORIZED);response.getWriter().write("Token is invalid or expired");return false; // 拦截请求，不继续执行后续的处理器}}}return true; // 继续执行后续的处理器}private boolean validateToken(String token) {// TODO 这里添加你的逻辑来验证token的合法性// 这里添加你的token验证逻辑// 返回true表示token有效，返回false表示无效或过期return "expected-token-value".equals(token);}}

方法注册到Spring

import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;@Configuration
public class WebConfig implements WebMvcConfigurer {@Overridepublic void addInterceptors(InterceptorRegistry registry) {registry.addInterceptor(new TokenInterceptor());}
}

controller直接调用

import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;@RestController
public class UserController {@CheckToken @GetMapping("/user")public String user() {return "This is a test endpoint";}
}