项目源码-SpringBoot项目-创建及使用

Last Updated on 2025年1月17日 by hangzi

一、创建项目

1、打开IDEA，通过New Project创建项目，如下图：

2、选择Spring Initializr，配置好项目信息，点击Next，如下图：

3、选择依赖，点击Create，创建项目成功，如下图：

4、删除一些没啥用的文件及文件夹，只保留源码相关的文件，如下图：

5、最后保留下项目结构是这样的，如下图：

二、使用项目

搭建的项目主体框架是SpringBoot+Mybatis模式

1、修改配置文件格式和pom.xml排版

每个人都有自己的习惯，我个人的习惯是会修改配置文件格式和pom.xml排版

• pom.xml排版如下:

<?xml version="1.0" encoding="UTF-8"?>
<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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.hz</groupId>
    <artifactId>SpringBoot-Demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>

    <name>${project.artifactId}</name>
    <description>基于 Java 17 + SpringBoot3 创建的Demo项目</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>3.4.1</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <java.version>17</java.version>
        <maven.compiler.source>17</maven.compiler.source>
        <maven.compiler.target>17</maven.compiler.target>

        <hutool.version>5.8.27</hutool.version>
        <mysql.version>8.0.33</mysql.version>
        <mybatis-plus.version>3.5.9</mybatis-plus.version>

    </properties>
    <dependencies>

        <!--lombok 只在编译期间需要-->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <scope>provided</scope>
        </dependency>

        <!--工具类包-->
        <dependency>
            <groupId>cn.hutool</groupId>
            <artifactId>hutool-all</artifactId>
            <version>${hutool.version}</version>
        </dependency>

        <!-- mysql数据库连接包-->
        <dependency>
            <groupId>com.mysql</groupId>
            <artifactId>mysql-connector-j</artifactId>
        </dependency>

        <!-- mybatis-plus 见：dependencyManagement下管理 start-->

        <!-- springboot3 -->
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-spring-boot3-starter</artifactId>
        </dependency>
        <!-- 分页插件-->
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-jsqlparser</artifactId>
        </dependency>

        <!--代码生成器-->
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-generator</artifactId>
        </dependency>
        <!-- 代码生成器需要的模版-->
        <dependency>
            <groupId>org.apache.velocity</groupId>
            <artifactId>velocity-engine-core</artifactId>
            <version>2.3</version>
        </dependency>

        <!-- mybatis-plus end -->

        <!-- springboot web包（默认是web服务是tomcat） -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <!-- springboot test测试包 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <dependencyManagement>
        <dependencies>
            <!-- 通过mybatis-plus-bom管理依赖，减少版本号的冲突  -->
            <dependency>
                <groupId>com.baomidou</groupId>
                <artifactId>mybatis-plus-bom</artifactId>
                <version>${mybatis-plus.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <build>

        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

配置文件格式修改，由原始Properties格式：application.properties，修改为YAML格式：application.yml,如下图：

• application.yml内容如下：

# web服务配置
server:
  port: 8080
  # 给项目添加前缀，这个可以加也可以不加
  servlet:
    context-path: /demo

spring:
  # 项目名称
  application:
    name: SpringBoot-Demo

  # 数据库配置
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://127.0.0.1:3307/demo?zeroDateTimeBehavior=convertToNull&useUnicode=true&characterEncoding=UTF-8&serverTimezone=Asia/Shanghai&autoReconnect=true&allowMultiQueries=true
    username: root
    password: root

# mybatis
mybatis-plus:
  global-config:
    db-config:
      # 主键ID类型
      id-type: none
      # 逻辑删除字段名称
      # logic-delete-field: deleted
      # 逻辑删除-删除值
      logic-delete-value: 1
      # 逻辑删除-未删除值
      logic-not-delete-value: 0
  configuration:
    map-underscore-to-camel-case: true
    cache-enabled: false
    call-setters-on-nulls: true
    jdbc-type-for-null: 'null'
    # 这个配置会将执行的sql打印出来，在开发或测试的时候可以用
    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl

检查项目是否能正常启动，如下图：

以User表进行简单增删改查为例

项目结构，如图：

Java三层架构的三个层次：控制层（UserController）,业务逻辑层（UserService 、UserServiceImpl）,数据访问层（UserDao、UserDao.xml）

• user表：

CREATE TABLE `user`  (
  `id` bigint NOT NULL AUTO_INCREMENT COMMENT '主键',
  `username` varchar(100)  NOT NULL COMMENT '用户名',
  `password` varchar(100)  NOT NULL COMMENT '密码',
  `create_time` datetime NULL DEFAULT NULL COMMENT '创建时间',
  `update_time` datetime NULL DEFAULT NULL COMMENT '更新时间',
  PRIMARY KEY (`id`) USING BTREE
) COMMENT = '用户表';

• User实体类：

/**
 * <p>
 * 用户表
 * </p>
 *
 * @author hz
 * @since 2025-01-06
 */
@Getter
@Setter
public class User implements Serializable {

    private static final long serialVersionUID = 1L;

    /**
     * 主键
     */
    @TableId(value = "id", type = IdType.AUTO)
    private Long id;

    /**
     * 用户名
     */
    private String username;

    /**
     * 密码
     */
    private String password;

    /**
     * 创建时间
     */
    @TableField(fill = FieldFill.INSERT)
    @JsonInclude(value = JsonInclude.Include.NON_NULL)
    @JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")
    private Date createTime;

    /**
     * 更新时间
     */
    @TableField(fill = FieldFill.INSERT_UPDATE)
    @JsonInclude(value = JsonInclude.Include.NON_NULL)
    @JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")
    private Date updateTime;
}

• UserMapper接口类：

/**
 * <p>
 * 用户表 Mapper 接口
 * </p>
 *
 * @author hz
 * @since 2025-01-06
 */
@Mapper
public interface UserMapper extends BaseMapper<User> {

    Page<User> listPagedUsers(Page<User> page, UserPageQuery queryParams);
}

• UserMapper.xml mybatis写sql语句的位置：

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.hz.mapper.UserMapper">

    <!-- 通用查询映射结果 -->
    <resultMap id="BaseResultMap" type="com.hz.model.User">
        <id column="id" property="id" />
        <result column="username" property="username" />
        <result column="password" property="password" />
        <result column="create_time" property="createTime" />
        <result column="update_time" property="updateTime" />
    </resultMap>

    <!-- 通用查询结果列 -->
    <sql id="Base_Column_List">
        id, username,password,create_time, update_time
    </sql>

    <!-- 分页列表 -->
    <select id="listPagedUsers" resultMap="BaseResultMap">
        SELECT
        <include refid="Base_Column_List"/>
        FROM
        user
        <where>
            1=1
            <if test="queryParams.username != null">
                AND username LIKE CONCAT('%',#{queryParams.username},'%')
            </if>
        </where>
        ORDER BY create_time DESC
    </select>
</mapper>

• UserService接口类：

/**
 * <p>
 * 用户表 服务类
 * </p>
 *
 * @author hz
 * @since 2025-01-06
 */
public interface IUserService extends IService<User> {

    IPage<User> listPagedUsers(UserPageQuery queryParams);

    boolean saveUser(User formData);

    User getUserFormData(Long id);

    boolean updateUser(User formData);

    boolean deleteUsers(String ids);
}

• UserServiceImpl实现类：

/**
 * <p>
 * 用户表 服务实现类
 * </p>
 *
 * @author hz
 * @since 2025-01-06
 */
@Service
public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements IUserService {

    @Override
    public IPage<User> listPagedUsers(UserPageQuery queryParams) {
        int pageNum = queryParams.getPageNum();
        int pageSize = queryParams.getPageSize();
        Page<User> page = new Page<>(pageNum, pageSize);
        return this.baseMapper.listPagedUsers(page, queryParams);
    }

    @Override
    public boolean saveUser(User formData) {
        return this.save(formData);
    }

    @Override
    public User getUserFormData(Long id) {
        return this.getById(id);
    }

    @Override
    public boolean updateUser(User formData) {
        return this.updateById(formData);
    }

    @Override
    public boolean deleteUsers(String ids) {
        Assert.isTrue(StrUtil.isNotBlank(ids), "删除的数据为空");
        List<Long> idList = Arrays.stream(ids.split(","))
                .map(Long::parseLong)
                .toList();
        return this.removeByIds(idList);
    }
}

• UserController控制层：

/**
 * <p>
 * 用户表 前端控制器
 * </p>
 *
 * @author hz
 * @since 2025-01-06
 */
@RestController
@RequestMapping("/user")
@RequiredArgsConstructor
public class UserController {

    private final IUserService userService;

    /**
     * 分页列表
     */
    @GetMapping("/page")
    public PageResult<User> listPagedUsers(UserPageQuery queryParams ) {
        IPage<User> result = userService.listPagedUsers(queryParams);
        return PageResult.success(result);
    }

    /**
     * 新增
     */
    @PostMapping
    public Result saveUser(@RequestBody User formData ) {
        boolean result = userService.saveUser(formData);
        return Result.judge(result);
    }

    /**
     * 根据id获取详情
     */
    @GetMapping("/{id}")
    public Result getUserForm(@PathVariable Long id) {
        User formData = userService.getUserFormData(id);
        return Result.success(formData);
    }

    /**
     * 修改
     */
    @PutMapping(value = "/{id}")
    public Result updateUser(@RequestBody User formData) {
        boolean result = userService.updateUser(formData);
        return Result.judge(result);
    }

    /**
     * 删除
     */
    @DeleteMapping("/{ids}")
    public Result deleteUsers(@PathVariable String ids) {
        boolean result = userService.deleteUsers(ids);
        return Result.judge(result);
    }

}

简单流程过程，如下图：

mybatis-plus快速生成代码：

@SpringBootTest
public class CodeGeneratorTest {

    @Test
    public void codeGenerator() {
        FastAutoGenerator.create("jdbc:mysql://127.0.0.1:3306/demo", "root", "root")
                .globalConfig(builder -> builder
                        .disableOpenDir()
                        .author("hz")
                        .dateType(DateType.ONLY_DATE)
                        .outputDir(Paths.get(System.getProperty("user.dir")) + "/src/main/java")
                        .commentDate("yyyy-MM-dd")
                )
                .packageConfig(builder -> builder
                        .parent("com.hz")
                        .entity("model")
                        .mapper("mapper")
                        .service("service")
                        .serviceImpl("service.impl")
                        //自定义mapper.xml文件输出目录
                        .pathInfo(Collections.singletonMap(OutputFile.xml,Paths.get(System.getProperty("user.dir")) + "/src/main/resources/mapper"))
                )
                .strategyConfig(builder -> builder
                        .entityBuilder()
                        .enableLombok()
                )
                .execute();
    }
}

附项目源码：https://github.com/hangzhi7/SpringBoot-Demo