基础版

controller

package com.web.management.controller;import com.web.management.pojo.Emp;
import com.web.management.pojo.Result;
import com.web.management.service.EmpService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RestController;import java.util.List;@Slf4j
@RestController
public class LoginController {@Autowiredprivate EmpService  empService;@PostMapping("/login")public Result login(@RequestBody Emp emp) {log.info("登录账号和密码：{}", emp);Emp e = empService.login(emp);
//        if(emp != null) {
//            return Result.success(emp);
//        }else {
//            return Result.error("账号或密码错误");
//        }return e != null?Result.success(e):Result.error("账号或密码错误");}
}

service

Emp login(Emp em);

serviceimpl

    @Overridepublic Emp login(Emp emp) {return empMapper.getByUsernameAndPassword(emp);}

mapper

    @Select("SELECT * from emp where username = #{username} and password = #{password}")Emp getByUsernameAndPassword(Emp emp);

添加依赖

在pom.xml中，记得刷新

        <!--阿里云OSS--><dependency><groupId>com.aliyun.oss</groupId><artifactId>aliyun-sdk-oss</artifactId><version>3.15.1</version></dependency><dependency><groupId>javax.xml.bind</groupId><artifactId>jaxb-api</artifactId><version>2.3.1</version></dependency><dependency><groupId>javax.activation</groupId><artifactId>activation</artifactId><version>1.1.1</version></dependency><!-- no more than 2.3.3--><dependency><groupId>org.glassfish.jaxb</groupId><artifactId>jaxb-runtime</artifactId><version>2.3.3</version></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-configuration-processor</artifactId></dependency><!--JWT令牌--><dependency><groupId>io.jsonwebtoken</groupId><artifactId>jjwt</artifactId><version>0.9.1</version></dependency><!--fastJSON--><dependency><groupId>com.alibaba</groupId><artifactId>fastjson</artifactId><version>1.2.76</version></dependency>

登录校验

cookie

package com.web.management.controller;import com.web.management.pojo.Result;
import jakarta.servlet.http.Cookie;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import lombok.extern.slf4j.Slf4j;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;@Slf4j
@RestController
public class CookieOrSessionController {//    设置cookie@GetMapping("/c1")public Result cookie1(HttpServletResponse response) {response.addCookie(new Cookie("login_username","www123")); //设置Cookie/响应Cookiereturn Result.success();}//获取Cookie@GetMapping("/c2")public Result cookie2(HttpServletRequest request){Cookie[] cookies = request.getCookies();for (Cookie cookie : cookies) {if(cookie.getName().equals("login_username")){System.out.println("login_username: "+cookie.getValue()); //输出name为login_username的cookie}}return Result.success();}}

 

session

package com.web.management.controller;import com.web.management.pojo.Result;
import jakarta.servlet.http.Cookie;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import jakarta.servlet.http.HttpSession;
import lombok.extern.slf4j.Slf4j;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;@Slf4j
@RestController
public class CookieOrSessionController {@GetMapping("/s1")public Result session1(HttpSession session){log.info("HttpSession-s1: {}", session.hashCode());session.setAttribute("loginUser", "tom"); //往session中存储数据return Result.success();}@GetMapping("/s2")public Result session2(HttpServletRequest request){HttpSession session = request.getSession();log.info("HttpSession-s2: {}", session.hashCode());Object loginUser = session.getAttribute("loginUser"); //从session中获取数据log.info("loginUser: {}", loginUser);return Result.success(loginUser);}}

JWT令牌

package com.web.management.util;import io.jsonwebtoken.Claims;
import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.SignatureAlgorithm;
import java.util.Date;
import java.util.Map;public class JwtUtils {private static String signKey = "www123";private static Long expire = 43200000L;/*** 生成JWT令牌* @param claims JWT第二部分负载 payload 中存储的内容* @return*/public static String generateJwt(Map<String, Object> claims){String jwt = Jwts.builder().addClaims(claims).signWith(SignatureAlgorithm.HS256, signKey).setExpiration(new Date(System.currentTimeMillis() + expire)).compact();return jwt;}/*** 解析JWT令牌* @param jwt JWT令牌* @return JWT第二部分负载 payload 中存储的内容*/public static Claims parseJWT(String jwt){Claims claims = Jwts.parser().setSigningKey(signKey).parseClaimsJws(jwt).getBody();return claims;}
}

实现

package com.web.management.controller;import com.web.management.pojo.Emp;
import com.web.management.pojo.Result;
import com.web.management.service.EmpService;
import com.web.management.util.JwtUtils;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RestController;import java.util.HashMap;
import java.util.List;
import java.util.Map;@Slf4j
@RestController
public class LoginController {@Autowiredprivate EmpService  empService;@PostMapping("/login2")public Result login2(@RequestBody Emp emp) {log.info("登录账号和密码：{}", emp);Emp e = empService.login(emp);if(emp != null) {Map<String , Object> claims = new HashMap<>();claims.put("id",e.getId());claims.put("name",e.getName());claims.put("username",e.getUsername());String jwt = JwtUtils.generateJwt(claims);return Result.success(jwt);}else {return Result.error("账号或密码错误");}}
}

其他层与基础版登录一致

过滤器Filter

package com.web.management.filter;import jakarta.servlet.*;
import jakarta.servlet.annotation.WebFilter;import java.io.IOException;@WebFilter(urlPatterns = "/*")
public class DemoFilter implements Filter {@Overridepublic void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {System.out.println("拦截方法执行，拦截到了请求...");filterChain.doFilter(servletRequest, servletResponse);//放行}
}

知识点

  

实现

package com.web.management.filter;import com.alibaba.fastjson.JSONObject;
import com.google.gson.JsonObject;
import com.web.management.pojo.Result;
import com.web.management.util.JwtUtils;
import jakarta.servlet.*;
import jakarta.servlet.annotation.WebFilter;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.StringUtils;import java.io.IOException;@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是：{}",url);//        2、判断url是否为login，如果是登录操作，放行。if (url.contains("login")) {log.info("正在进行登录操作...");filterChain.doFilter(servletRequest, servletResponse);return;}//        3、获取请求头中的令牌（token）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）
//        导入import org.springframework.util.StringUtils;if(!StringUtils.hasLength(jwt)){log.info("请求头token为空，未登录");Result error = Result.error("NOT_LOGIN");
//            手动转换为json格式，利用阿里巴巴fastjson，导入依赖String notLogin = JSONObject.toJSONString(error);resp.getWriter().write(notLogin);return;}//        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) {e.printStackTrace();log.info("解析失败，未登录");Result error = Result.error("NOT_LOGIN");
//            手动转换为json格式，利用阿里巴巴fastjson，导入依赖String notLogin = JSONObject.toJSONString(error);resp.getWriter().write(notLogin);return;}//        放行log.info("令牌合法，放行");filterChain.doFilter(servletRequest, servletResponse);}
}

拦截器interceptor

要使用拦截器，记得把过滤器的注解注释了

入门

package com.web.management.interceptor;import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;@Component
public class LoginCheckInterceptor implements HandlerInterceptor {
//目标资源方法执行前执行，返回true，放行，放回flase，不放行@Overridepublic boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {System.out.println("preHandle....");return true;}
//目标资源方法执行后执行@Overridepublic void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {HandlerInterceptor.super.postHandle(request, response, handler, modelAndView);}
//视图渲染完毕后执行，最后执行@Overridepublic void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {HandlerInterceptor.super.afterCompletion(request, response, handler, ex);}
}

package com.web.management.config;import com.web.management.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;@Configuration
public class WebConfig implements WebMvcConfigurer {@Autowiredprivate LoginCheckInterceptor loginCheckInterceptor;@Overridepublic void addInterceptors(InterceptorRegistry registry) {
//        设置拦截什么registry.addInterceptor(loginCheckInterceptor).addPathPatterns("/**").excludePathPatterns("/login");}
}

知识点

实现

package com.web.management.interceptor;import com.alibaba.fastjson.JSONObject;
import com.web.management.pojo.Result;
import com.web.management.util.JwtUtils;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;
@Slf4j
@Component
public class LoginCheckInterceptor implements HandlerInterceptor {
//目标资源方法执行前执行，返回true，放行，放回flase，不放行@Overridepublic boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {System.out.println("preHandle....");//        1、获取请求urlString url = request.getRequestURI().toString();log.info("请求的url是：{}",url);//        2、判断url是否为login，如果是登录操作，放行。if (url.contains("login")) {log.info("正在进行登录操作...");return true;}//        3、获取请求头中的令牌（token）String jwt = request.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）
//        导入import org.springframework.util.StringUtils;if(!StringUtils.hasLength(jwt)){log.info("请求头token为空，未登录");Result error = Result.error("NOT_LOGIN");
//            手动转换为json格式，利用阿里巴巴fastjson，导入依赖String notLogin = JSONObject.toJSONString(error);response.getWriter().write(notLogin);return true;}//        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) {e.printStackTrace();log.info("解析失败，未登录");Result error = Result.error("NOT_LOGIN");
//            手动转换为json格式，利用阿里巴巴fastjson，导入依赖String notLogin = JSONObject.toJSONString(error);response.getWriter().write(notLogin);return true;}//        放行log.info("令牌合法，放行");return true;}
//目标资源方法执行后执行@Overridepublic void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {HandlerInterceptor.super.postHandle(request, response, handler, modelAndView);}
//视图渲染完毕后执行，最后执行@Overridepublic void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {HandlerInterceptor.super.afterCompletion(request, response, handler, ex);}
}

关于过滤器和拦截器放行

过滤器：

filterChain.doFilter(servletRequest, servletResponse);

拦截器：

return true;

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