过滤器Filter，拦截器Interceptor

package com.itheima.filter;import com.alibaba.fastjson.JSONObject;
import com.itheima.pojo.Result;
import com.itheima.utils.JwtUtils;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.StringUtils;import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;/*** @author Mr.jia* @version 1.0*/
@Slf4j
@WebFilter(urlPatterns = "/*")
public class LoginCheckFilter implements Filter {@Overridepublic void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {HttpServletRequest req = (HttpServletRequest) servletRequest;HttpServletResponse resp = (HttpServletResponse) servletResponse;//1.获取请求urlString url = req.getRequestURI().toString();log.info("请求的url：{}",url);//2.判断请求url中是否包含login，如果包含，说明是登录操作，放行if(url.contains("login")){log.info("登录操作，放行...");filterChain.doFilter(servletRequest,servletResponse);return;}//3.获取请求头中的令牌String jwt = req.getHeader("token");//4.判断令牌是否存在，如果不存在，返回错误结果（未登录）if(!StringUtils.hasLength(jwt)){log.info("请求头token为空，返回登录的信息");Result error = Result.error("NOT_LOGIN");//手动转换  对象---json----->阿里巴巴fastJSONString notLogin = JSONObject.toJSONString(error);resp.getWriter().write(notLogin);return;}//5.解析token，如果解析失败，返回错误结果（未登录）try {JwtUtils.parseJWT(jwt);} catch (Exception e) {//解析失败e.printStackTrace();log.info("解析令牌失败，返回登录的信息");Result error = Result.error("NOT_LOGIN");//手动转换  对象---json----->阿里巴巴fastJSONString notLogin = JSONObject.toJSONString(error);resp.getWriter().write(notLogin);return;}//6.放行log.info("令牌合法，放行");filterChain.doFilter(servletRequest,servletResponse);}
}

package com.itheima.interceptor;import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;/*** @author Mr.jia* @version 1.0*/
@Component
public class LoginCheckInterceptor implements HandlerInterceptor {@Override //目标资源方法运行前运行，返回true：放行，false：不放行public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {return true;}@Override //目标资源方法运行后运行public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {System.out.println("postHandle");}@Override //视图渲染完毕后运行，最后运行public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {System.out.println("afterCompletion");}
}

定义拦截器

package com.itheima.config;import com.itheima.interceptor.LoginCheckInterceptor;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;/*** @author Mr.jia* @version 1.0*/
@Configuration//配置类
public class WebConfig implements WebMvcConfigurer {@Autowiredprivate LoginCheckInterceptor loginCheckInterceptor;@Overridepublic void addInterceptors(InterceptorRegistry registry){registry.addInterceptor(loginCheckInterceptor).addPathPatterns("/**");}
}

配置拦截器

/*** @author Mr.jia* @version 1.0*/
@Slf4j
@Component
public class LoginCheckInterceptor implements HandlerInterceptor {@Override //目标资源方法运行前运行，返回true：放行，false：不放行public boolean preHandle(HttpServletRequest servletRequest, HttpServletResponse servletResponse, Object handler) throws Exception {//1.获取请求urlString url = servletRequest.getRequestURI().toString();log.info("请求的url：{}",url);//2.判断请求url中是否包含login，如果包含，说明是登录操作，放行if(url.contains("login")){log.info("登录操作，放行...");return true;}//3.获取请求头中的令牌String jwt = servletRequest.getHeader("token");//4.判断令牌是否存在，如果不存在，返回错误结果（未登录）if(!StringUtils.hasLength(jwt)){log.info("请求头token为空，返回登录的信息");Result error = Result.error("NOT_LOGIN");//手动转换  对象---json----->阿里巴巴fastJSONString notLogin = JSONObject.toJSONString(error);servletResponse.getWriter().write(notLogin);return false;}//5.解析token，如果解析失败，返回错误结果（未登录）try {JwtUtils.parseJWT(jwt);} catch (Exception e) {//解析失败e.printStackTrace();log.info("解析令牌失败，返回登录的信息");Result error = Result.error("NOT_LOGIN");//手动转换  对象---json----->阿里巴巴fastJSONString notLogin = JSONObject.toJSONString(error);servletResponse.getWriter().write(notLogin);return false;}//6.放行log.info("令牌合法，放行");return true;}@Override //目标资源方法运行后运行public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {System.out.println("postHandle");}@Override //视图渲染完毕后运行，最后运行public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {System.out.println("afterCompletion");}
}