Java 小项目开发日记 03（文章分类接口的开发）

项目目录

配置文件（pom.xml）

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"><modelVersion>4.0.0</modelVersion><!--继承父工程--><parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>3.1.6</version></parent><groupId>com.zhong</groupId><artifactId>big-event</artifactId><version>1.0-SNAPSHOT</version><packaging>jar</packaging><name>big-event</name><url>http://maven.apache.org</url><properties><project.build.sourceEncoding>UTF-8</project.build.sourceEncoding></properties><dependencies><!--web 依赖--><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><!--MyBatis 依赖--><dependency><groupId>org.mybatis.spring.boot</groupId><artifactId>mybatis-spring-boot-starter</artifactId><version>3.0.0</version></dependency><!--MySQL 依赖--><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><version>8.0.29</version></dependency><!--lombok 依赖--><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId></dependency><!--参数校验依赖--><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-validation</artifactId></dependency><!--jwt 令牌验证--><dependency><groupId>com.auth0</groupId><artifactId>java-jwt</artifactId><version>4.4.0</version></dependency><!--单元测试依赖--><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId></dependency></dependencies>
</project>

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resources 配置

• resources
  • application.yml

spring:datasource:driver-class-name: com.mysql.cj.jdbc.Driverurl: jdbc:mysql://localhost:3306/big_eventusername: rootpassword: 123456
mybatis:configuration:map-underscore-to-camel-case: true    # 开启下划线映射

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config

• WebConfig

package com.zhong.config;import com.zhong.interceptors.LoginInterceptor;
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;/*** @ClassName : WebConfig* @Description : Web 配置* @Author : zhx* @Date: 2024-02-28 19:30*/
@Configuration
public class WebConfig implements WebMvcConfigurer {@Autowiredprivate LoginInterceptor loginInterceptor;@Overridepublic void addInterceptors(InterceptorRegistry registry) {registry.addInterceptor(loginInterceptor).excludePathPatterns("/user/login", "/user/register");}
}

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controller

• CategoryController

package com.zhong.controller;import com.zhong.pojo.Category;
import com.zhong.pojo.Result;
import com.zhong.service.CategoryService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.bind.annotation.*;import java.util.List;/*** @ClassName : CategoryController* @Description : 文章操作* @Author : zhx* @Date: 2024-02-29 19:46*/
@RestController
@RequestMapping("/category")
public class CategoryController {@Autowiredprivate CategoryService categoryService;@PostMappingpublic Result add(@RequestBody @Validated(Category.Add.class) Category category) {categoryService.add(category);return Result.success();}@GetMappingpublic Result<List<Category>> findAll() {List<Category> category = categoryService.findAll();return Result.success(category);}@GetMapping("/detail")public Result<Category> findCategoryById(@RequestHeader @Validated(Category.Update.class) Integer id) {return Result.success(categoryService.findCategoryById(id));}@PutMappingpublic Result updateCategory(@RequestBody @Validated(Category.Update.class) Category category) {categoryService.updateCategory(category);return Result.success();}@DeleteMappingpublic Result deleteCategory(@RequestHeader @Validated(Category.Update.class) Integer id){categoryService.deleteCategory(id);return Result.success();}
}

• UserController

package com.zhong.controller;import com.zhong.pojo.Result;
import com.zhong.pojo.User;
import com.zhong.service.UserService;
import com.zhong.utils.JwtUtil;
import com.zhong.utils.Md5Util;
import com.zhong.utils.ThreadLocalUtil;
import jakarta.validation.constraints.Pattern;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.util.StringUtils;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.bind.annotation.*;import java.util.HashMap;
import java.util.Map;/*** @ClassName : UserController* @Description : 用户操作* @Author : zhx* @Date: 2024-02-27 20:40*/
@RestController
@RequestMapping("/user")
@Validated
public class UserController {@Autowiredprivate UserService userService;@PostMapping("/register")public Result register(@Pattern(regexp = "^\\S{6,16}$") String username, @Pattern(regexp = "^\\S{6,16}$") String password) {// 查询用户User user = userService.findByUserName(username);if (user == null) {// 没有被占用// 注册userService.registerUser(username, password);return Result.success();} else {// 被占用return Result.error("用户名已被占用......");}}@PostMapping("/login")public Result<String> login(@Pattern(regexp = "^\\S{2,10}$") String username, @Pattern(regexp = "^\\S{6,16}$") String password) {User user = userService.findByUserName(username);// 密码正确 登录if (user == null) {return Result.error("用户不存在......");}if (Md5Util.checkPassword(password, user.getPassword())) {  // 验证用户密码HashMap<String, Object> claims = new HashMap<>();   // 创建校验mapclaims.put("id", user.getId()); // 添加用户 IDclaims.put("username", user.getUsername()); // 添加用户名return Result.success(JwtUtil.genToken(claims));    // 返回获取到的 token}return Result.error("密码错误......");}@GetMapping("/userinfo")public Result<User> getUserInfo() {// 获取线程中的 user 对象Map<String, Object> user = ThreadLocalUtil.get();User userInfo = userService.getUserInfo((Integer) user.get("id"));return Result.success(userInfo);}@PutMapping("/update")public Result update(@RequestBody @Validated User user) {if (!userService.update(user)) {return Result.error("修改失败......");}return Result.success("修改成功！");}@PatchMapping("/updatepwd")public Result updatePassWord(@RequestBody Map<String, String> params) {String oldPwd = params.get("old_pwd");String newPwd = params.get("new_pwd");String rePwd = params.get("re_pwd");if (oldPwd.equals(newPwd) || oldPwd.equals(rePwd)) {return Result.error("修改密码与原密码相同......");}if (!StringUtils.hasLength(oldPwd) || !StringUtils.hasLength(newPwd) || !StringUtils.hasLength(rePwd)){return Result.error("密码不能为空......");}if (!newPwd.equals(rePwd)) {return Result.error("新密码不一致......");}if (!userService.updatePassWord(oldPwd, newPwd)){return Result.error("原密码不匹配......");}return Result.success("修改密码成功！");}
}

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exception

• GlobalExceptionHandler

package com.zhong.exception;import com.zhong.pojo.Result;
import org.springframework.util.StringUtils;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RestControllerAdvice;/*** @ClassName : GlobalExceptionHandler* @Description : 全局异常处理* @Author : zhx* @Date: 2024-02-27 21:37*/
@RestControllerAdvice
public class GlobalExceptionHandler {@ExceptionHandler(Exception.class)public Result handlerException(Exception e) {e.printStackTrace();return Result.error(StringUtils.hasLength(e.getMessage()) ? e.getMessage() : "操作失败");}
}

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interceptors

• LoginInterceptor

package com.zhong.interceptors;import com.zhong.utils.JwtUtil;
import com.zhong.utils.ThreadLocalUtil;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;import java.util.Map;/*** @ClassName : LoginInterceptor* @Description : 登录拦截器* @Author : zhx* @Date: 2024-02-28 19:25*/
@Component
public class LoginInterceptor implements HandlerInterceptor {@Overridepublic boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {// 获取浏览器中的 tokenString token = request.getHeader("Authorization");// 解析 tokentry {Map<String, Object> claims = JwtUtil.parseToken(token);// 把得到的数据存入 ThreadLocalThreadLocalUtil.set(claims);// 放行return true;} catch (Exception e) {response.setStatus(401);// 拦截return false;}}@Overridepublic void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {// 清空 ThreadLocal 中的数据  防止内存泄漏ThreadLocalUtil.remove();}
}

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mapper

• CategoryMapper

package com.zhong.mapper;import com.zhong.pojo.Category;
import org.apache.ibatis.annotations.*;import java.util.List;/*** @ClassName : CategoryMapper* @Description : 文章SQL* @Author : zhx* @Date: 2024-02-29 19:50*/
@Mapper
public interface CategoryMapper {@Insert("insert into category(category_name, category_alias, create_user, create_time, update_time) values (#{categoryName}, #{categoryAlias}, #{createUser} , now(), now())")void add(Category category);@Select("select * from category where create_user = #{userId}")List<Category> findAll(Integer userId);@Select("select * from category where id = #{id}")Category findCategoryById(Integer id);@Update("update category set category_name = #{categoryName}, category_alias = #{categoryAlias}, update_time = now() where id = #{id}")void updateCategory(Category category);@Delete("delete from category where id = #{id}")void deleteCategory(Integer id);
}

• UserMapper

package com.zhong.mapper;import com.zhong.pojo.User;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.annotations.Update;/*** @ClassName : UserMapper* @Description : 用户业务逻辑* @Author : zhx* @Date: 2024-02-27 20:42*/
@Mapper
public interface UserMapper {// 根据用户名查询用户@Select("select * from user where username = #{username}")User findByUserName(String username);// 添加用户@Insert("insert into user(username, password, create_time, update_time) values (#{username}, #{password}, now(), now()) ")void registerUser(String username, String password);@Select("select * from user where id = #{id}")User getUserInfo(Integer id);@Update("update user set username = #{user.username}, nickname = #{user.nickname}, email = #{user.email}, user_pic=#{user.userPic}, update_time = now() where id = #{myId};")Boolean update(User user,Integer myId);@Update("update user set password = #{newP}, update_time = now() where id= #{id} AND password = #{oldP}")boolean updatePassWord(Integer id, String oldP, String newP);
}

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pojo

• Category

package com.zhong.pojo;import com.fasterxml.jackson.annotation.JsonFormat;
import com.fasterxml.jackson.annotation.JsonIgnore;
import jakarta.validation.constraints.NotEmpty;
import jakarta.validation.constraints.NotNull;
import jakarta.validation.groups.Default;
import lombok.Builder;
import lombok.Data;
import java.time.LocalDateTime;@Data
public class Category {@NotNull(groups = Update.class)private Integer id;//主键ID@NotEmptyprivate String categoryName;//分类名称@NotEmptyprivate String categoryAlias;//分类别名@JsonIgnore // 转换成 json 的时候忽略该字段private Integer createUser;//创建人ID@JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")private LocalDateTime createTime;//创建时间@JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")private LocalDateTime updateTime;//更新时间// Default 继承默认分组 不添加分组信息则是默认分组public interface Add extends Default {}public interface Update extends Default{}
}

• Result

package com.zhong.pojo;import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;//统一响应结果
@AllArgsConstructor
@NoArgsConstructor
@Data
public class Result<T> {private Integer code;//业务状态码  0-成功  1-失败private String message;//提示信息private T data;//响应数据//快速返回操作成功响应结果(带响应数据)public static <E> Result<E> success(E data) {return new Result<>(0, "操作成功", data);}//快速返回操作成功响应结果public static Result success() {return new Result(0, "操作成功", null);}public static Result error(String message) {return new Result(1, message, null);}
}

• User

package com.zhong.pojo;import com.fasterxml.jackson.annotation.JsonFormat;
import com.fasterxml.jackson.annotation.JsonIgnore;
import jakarta.validation.constraints.Email;
import jakarta.validation.constraints.NotEmpty;
import jakarta.validation.constraints.Pattern;
import lombok.Data;
import lombok.NoArgsConstructor;
import lombok.NonNull;
import org.hibernate.validator.constraints.URL;import java.time.LocalDateTime;
@Data
@NoArgsConstructor
public class User {@NonNullprivate Integer id;//主键ID@NotEmpty@Pattern(regexp = "^\\S{2,10}$")private String username;//用户名@JsonIgnore // 转换成 json 的时候忽略该字段private String password;//密码@NotEmpty@Pattern(regexp = "\\S{1,12}$")private String nickname;//昵称@NotEmpty@Emailprivate String email;//邮箱@URLprivate String userPic;//用户头像地址@JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")private LocalDateTime createTime;//创建时间@JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")private LocalDateTime updateTime;//更新时间
}

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service

• impl
  • CategoryServiceImpl

package com.zhong.service.impl;import com.zhong.mapper.CategoryMapper;
import com.zhong.pojo.Category;
import com.zhong.service.CategoryService;
import com.zhong.utils.GetNowLoginIdUtil;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;import java.util.List;/*** @ClassName : CategoryServiceImpl* @Description : 文章接口实现类* @Author : zhx* @Date: 2024-02-29 19:48*/
@Service
public class CategoryServiceImpl implements CategoryService {@Autowiredprivate CategoryMapper categoryMapper;@Overridepublic void add(Category category) {Integer id = GetNowLoginIdUtil.getID();category.setCreateUser(id);categoryMapper.add(category);}@Overridepublic List<Category> findAll() {Integer id = GetNowLoginIdUtil.getID();return categoryMapper.findAll(id);}@Overridepublic Category findCategoryById(Integer id) {return categoryMapper.findCategoryById(id);}@Overridepublic void updateCategory(Category category) {categoryMapper.updateCategory(category);}@Overridepublic void deleteCategory(Integer id) {categoryMapper.deleteCategory(id);}
}

• impl
  • UserServiceImpl

package com.zhong.service.impl;import com.auth0.jwt.JWT;
import com.auth0.jwt.JWTVerifier;
import com.auth0.jwt.algorithms.Algorithm;
import com.auth0.jwt.interfaces.Claim;
import com.auth0.jwt.interfaces.DecodedJWT;
import com.zhong.mapper.UserMapper;
import com.zhong.pojo.User;
import com.zhong.service.UserService;
import com.zhong.utils.JwtUtil;
import com.zhong.utils.Md5Util;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;import java.util.Map;/*** @ClassName : UserServiceImpl* @Description : 用户接口实现类* @Author : zhx* @Date: 2024-02-27 20:41*/
@Service
public class UserServiceImpl implements UserService {@Autowiredprivate UserMapper userMapper;@Overridepublic User findByUserName(String username) {return userMapper.findByUserName(username);}@Overridepublic void registerUser(String username, String password) {// 加密String md5String = Md5Util.getMD5String(password);// 添加userMapper.registerUser(username, md5String);}@Overridepublic User getUserInfo(Integer id) {return userMapper.getUserInfo(id);}@Overridepublic Boolean update(User user) {return userMapper.update(user);}}

• CategoryService

package com.zhong.service;import com.zhong.pojo.Category;import java.util.List;/*** @ClassName : CategoryService* @Description : 文章接口* @Author : zhx* @Date: 2024-02-29 19:47*/
public interface CategoryService {// 添加分类void add(Category category);List<Category> findAll();Category findCategoryById(Integer id);void updateCategory(Category category);void deleteCategory(Integer id);
}

• UserService

package com.zhong.service;import com.zhong.pojo.User;/*** @ClassName : UserService* @Description : 用户接口* @Author : zhx* @Date: 2024-02-27 20:40*/
public interface UserService {// 根据用户名查询用户User findByUserName(String username);// 注册用户void registerUser(String username, String password);User getUserInfo(Integer id);Boolean update(User user);
}

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utils

• GetNowLoginIdUtil

package com.zhong.utils;import java.util.Map;/*** @ClassName : GetNowLoginId* @Description : 获取当前用户登录的 id* @Author : zhx* @Date: 2024-02-29 20:32*/
public class GetNowLoginIdUtil {public static Integer getID(){Map<String, Object> claims = ThreadLocalUtil.get();return (Integer) claims.get("id");}
}

• JwtUtil

package com.zhong.utils;import com.auth0.jwt.JWT;
import com.auth0.jwt.algorithms.Algorithm;import java.util.Date;
import java.util.Map;public class JwtUtil {private static final String KEY = "zhong";//接收业务数据,生成token并返回public static String genToken(Map<String, Object> claims) {return JWT.create().withClaim("claims", claims).withExpiresAt(new Date(System.currentTimeMillis() + 1000 * 60 * 60 * 12)).sign(Algorithm.HMAC256(KEY));}//接收token,验证token,并返回业务数据public static Map<String, Object> parseToken(String token) {return JWT.require(Algorithm.HMAC256(KEY)).build().verify(token).getClaim("claims").asMap();}}

• Md5Util

package com.zhong.utils;import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;public class Md5Util {/*** 默认的密码字符串组合，用来将字节转换成 16 进制表示的字符,apache校验下载的文件的正确性用的就是默认的这个组合*/protected static char hexDigits[] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};protected static MessageDigest messagedigest = null;static {try {messagedigest = MessageDigest.getInstance("MD5");} catch (NoSuchAlgorithmException nsaex) {System.err.println(Md5Util.class.getName() + "初始化失败，MessageDigest不支持MD5Util。");nsaex.printStackTrace();}}/*** 生成字符串的md5校验值** @param s* @return*/public static String getMD5String(String s) {return getMD5String(s.getBytes());}/*** 判断字符串的md5校验码是否与一个已知的md5码相匹配** @param password  要校验的字符串* @param md5PwdStr 已知的md5校验码* @return*/public static boolean checkPassword(String password, String md5PwdStr) {String s = getMD5String(password);return s.equals(md5PwdStr);}public static String getMD5String(byte[] bytes) {messagedigest.update(bytes);return bufferToHex(messagedigest.digest());}private static String bufferToHex(byte bytes[]) {return bufferToHex(bytes, 0, bytes.length);}private static String bufferToHex(byte bytes[], int m, int n) {StringBuffer stringbuffer = new StringBuffer(2 * n);int k = m + n;for (int l = m; l < k; l++) {appendHexPair(bytes[l], stringbuffer);}return stringbuffer.toString();}private static void appendHexPair(byte bt, StringBuffer stringbuffer) {char c0 = hexDigits[(bt & 0xf0) >> 4];// 取字节中高 4 位的数字转换, >>>// 为逻辑右移，将符号位一起右移,此处未发现两种符号有何不同char c1 = hexDigits[bt & 0xf];// 取字节中低 4 位的数字转换stringbuffer.append(c0);stringbuffer.append(c1);}
}

• ThreadLocalUtil

package com.zhong.utils;/*** ThreadLocal 工具类*/
@SuppressWarnings("all")
public class ThreadLocalUtil {//提供ThreadLocal对象,private static final ThreadLocal THREAD_LOCAL = new ThreadLocal();//根据键获取值public static <T> T get(){return (T) THREAD_LOCAL.get();}//存储键值对public static void set(Object value){THREAD_LOCAL.set(value);}//清除ThreadLocal 防止内存泄漏public static void remove(){THREAD_LOCAL.remove();}
}

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BigEventApplication

package com.zhong;import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;@SpringBootApplication
public class BigEventApplication {public static void main(String[] args) {SpringApplication.run(BigEventApplication.class, args);}
}

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