基礎版

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("登錄賬號和密碼：{}", emp);Emp e = empService.login(emp);
//        if(emp != null) {
//            return Result.success(emp);
//        }else {
//            return Result.error("賬號或密碼錯誤");
//        }return e != null?Result.success(e):Result.error("賬號或密碼錯誤");}
}

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);

添加依賴

在pom.xml中，記得刷新

        <!--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>

登錄校驗

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 {//    設置cookie@GetMapping("/c1")public Result cookie1(HttpServletResponse response) {response.addCookie(new Cookie("login_username","www123")); //設置Cookie/響應Cookiereturn Result.success();}//獲取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()); //輸出name為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中存儲數據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"); //從session中獲取數據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第二部分負載 payload 中存儲的內容* @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第二部分負載 payload 中存儲的內容*/public static Claims parseJWT(String jwt){Claims claims = Jwts.parser().setSigningKey(signKey).parseClaimsJws(jwt).getBody();return claims;}
}

實現

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("登錄賬號和密碼：{}", 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("賬號或密碼錯誤");}}
}

其他層與基礎版登錄一致

過濾器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("攔截方法執行，攔截到了請求...");filterChain.doFilter(servletRequest, servletResponse);//放行}
}

知識點

??

實現

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、獲取請求urlString url = req.getRequestURI().toString();log.info("請求的url是：{}",url);//        2、判斷url是否為login，如果是登錄操作，放行。if (url.contains("login")) {log.info("正在進行登錄操作...");filterChain.doFilter(servletRequest, servletResponse);return;}//        3、獲取請求頭中的令牌（token）String jwt = req.getHeader("token");//        4、判斷令牌是否存在，如果不存在，返回錯誤結果（未登錄）
//        導入import org.springframework.util.StringUtils;if(!StringUtils.hasLength(jwt)){log.info("請求頭token為空，未登錄");Result error = Result.error("NOT_LOGIN");
//            手動轉換為json格式，利用阿里巴巴fastjson，導入依賴String notLogin = JSONObject.toJSONString(error);resp.getWriter().write(notLogin);return;}//        解析token，如果解析失敗，返回錯誤結果，未登錄try {JwtUtils.parseJWT(jwt);} catch (Exception e) {e.printStackTrace();log.info("解析失敗，未登錄");Result error = Result.error("NOT_LOGIN");
//            手動轉換為json格式，利用阿里巴巴fastjson，導入依賴String notLogin = JSONObject.toJSONString(error);resp.getWriter().write(notLogin);return;}//        放行log.info("令牌合法，放行");filterChain.doFilter(servletRequest, servletResponse);}
}

攔截器interceptor

要使用攔截器，記得把過濾器的注解注釋了

入門

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 {
//目標資源方法執行前執行，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;}
//目標資源方法執行后執行@Overridepublic void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {HandlerInterceptor.super.postHandle(request, response, handler, modelAndView);}
//視圖渲染完畢后執行，最后執行@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) {
//        設置攔截什么registry.addInterceptor(loginCheckInterceptor).addPathPatterns("/**").excludePathPatterns("/login");}
}

知識點

實現

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 {
//目標資源方法執行前執行，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、獲取請求urlString url = request.getRequestURI().toString();log.info("請求的url是：{}",url);//        2、判斷url是否為login，如果是登錄操作，放行。if (url.contains("login")) {log.info("正在進行登錄操作...");return true;}//        3、獲取請求頭中的令牌（token）String jwt = request.getHeader("token");//        4、判斷令牌是否存在，如果不存在，返回錯誤結果（未登錄）
//        導入import org.springframework.util.StringUtils;if(!StringUtils.hasLength(jwt)){log.info("請求頭token為空，未登錄");Result error = Result.error("NOT_LOGIN");
//            手動轉換為json格式，利用阿里巴巴fastjson，導入依賴String notLogin = JSONObject.toJSONString(error);response.getWriter().write(notLogin);return true;}//        解析token，如果解析失敗，返回錯誤結果，未登錄try {JwtUtils.parseJWT(jwt);} catch (Exception e) {e.printStackTrace();log.info("解析失敗，未登錄");Result error = Result.error("NOT_LOGIN");
//            手動轉換為json格式，利用阿里巴巴fastjson，導入依賴String notLogin = JSONObject.toJSONString(error);response.getWriter().write(notLogin);return true;}//        放行log.info("令牌合法，放行");return true;}
//目標資源方法執行后執行@Overridepublic void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {HandlerInterceptor.super.postHandle(request, response, handler, modelAndView);}
//視圖渲染完畢后執行，最后執行@Overridepublic void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {HandlerInterceptor.super.afterCompletion(request, response, handler, ex);}
}

關于過濾器和攔截器放行

過濾器：

filterChain.doFilter(servletRequest, servletResponse);

攔截器：

return true;

如果你覺得本文對你有用的話，請隨意打賞~

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