Spring Boot（一）使用Spring Initializr创建项目入门+整合Mybatis

落日映苍穹つ 2021-09-15 12:26 415阅读 0赞

### 前言 ###

spring boot 极大的简化了项目配置，比传统的SSM框架的开发效率更高。

### 开发准备 ###

1.  jdk1.8
2.  maven 3.5.0
3.  IDEA

### 开发步骤： ###

#### 1. 新建Spring Boot项目 ####

**    1.1 Intellij idea菜单栏File->new->project。**

![这里写图片描述][70]

**    1.2选择左侧栏中spring initializr，右侧选择jdk版本，以及默认的Service URL，点击next。**

![这里写图片描述][70 1]

**    1.3然后填写项目的Group、Artifact等信息，点击next。**

![这里写图片描述][70 2]

**    1.4左侧点击Web，中间一侧选择Web，然后左侧选择SQL，中间一侧选择JDBC、Mybatis、MYSQL（数据库用的是mysql，大家可以选择其他DB），点击next。**

![这里写图片描述][70 3]

![这里写图片描述][70 4]

**    1.5 至此，一个maven web项目就创建好了，目录结构如下。**  
![这里写图片描述][70 5]

#### 2. 创建文件夹形成web目录结构 ####

**    2.1 创建以下典型的web目录结构**

![这里写图片描述][70 6]

#### 3. 修改属性配置文件 ####

**    3.1 将 `application.properties`文件修改为`application.yml`文件**  
        原因：如果使用的是默认的`applica.properties`文件，会重复写许多配置式的前缀，并且不能够体现出结构化特点。

![这里写图片描述][70 7]

**    3.2 在pom.xml中添加依赖，防止默认寻找application.properties文件出错**

<dependency>
        <groupId> org.springframework.boot </groupId>
        <artifactId>spring-boot-configuration-processor</artifactId>
        <optional>true</optional>
    </dependency>

**    3.3 在application.yml文件中写入配置**

server:
      port: 8081  //访问端口号
    spring:
      datasource:  //数据库配置
        driver-class-name: com.mysql.jdbc.Driver
        url: jdbc:mysql://127.0.0.1:3306/angulardemo
        username: root
        password: wmj
    mybatis:  //Mybatis相关配置
      typeAliasesPackage: com.wmj.bootMybatis.Entity  //指明实体位置
      mapperLocations: classpath:Mapper/*.xml //配置Mapper.xml文件地址

#### 4. 在Spring Boot启动类中声明Dao层的位置 ####

package com.wmj.bootMybatis;
    
    import org.mybatis.spring.annotation.MapperScan;
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    
    @SpringBootApplication
    @MapperScan("com.wmj.bootMybatis.Dao")//非常重要
    public class BootMybatisApplication { 
    
        public static void main(String[] args) {
            SpringApplication.run(BootMybatisApplication.class, args);
        }
    }

#### 5. 像传统的是SSM开发模式进行开发 ####

**    5.1 开发目录结构如下**  
![这里写图片描述][70 8]

**    5.2 Entity层**

package com.wmj.springbootMybatis.Entity;
    
    public class Hero {
        private int id;
        private String name;
    
        public int getId() {
            return id;
        }
    
        public void setId(int id) {
            this.id = id;
        }
    
        public String getName() {
            return name;
        }
    
        public void setName(String name) {
            this.name = name;
        }
    }

**    5.2 Dao层**

package com.wmj.springbootMybatis.Dao;
    
    import com.wmj.springbootMybatis.Entity.Hero;
    
    import java.util.List;
    
    public interface HeroDao { 
        //获取所有英雄信息
        List<Hero> getAllHeroInfo();
        //获取所有英雄信息
        List<Hero> getHeroInfoById(Integer id);
        //获取查询英雄信息
        List<Hero> getHeroInfoByName(String name);
    
        //修改英雄信息
        int updateHeroInfo(Hero heroInfo);
        //获取现有英雄的最大ID
        int getMaxHeroId();
        //添加英雄信息
        int addHeroInfo(Hero hero);
    
        //根据学号删除英雄信息
        int deleteHeroInfo(Integer id);
    }

**    5.3 Dao层对应Mapper.xml文件**

<?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.wmj.springbootMybatis.Dao.HeroDao" >
        <resultMap id="heroResultMap" type="com.wmj.springbootMybatis.Entity.Hero" >
            <id column="id" property="id" jdbcType="INTEGER" />
            <result column="name" property="name" jdbcType="VARCHAR" />
        </resultMap>
    
        <select id="getAllHeroInfo"  parameterType="java.lang.Integer" resultMap="heroResultMap">
            select id,name from herotable
        </select>
        <select id="getHeroInfoById"  parameterType="java.lang.Integer" resultMap="heroResultMap">
            select id,name from herotable  where id = #{id}
        </select>
        <select id="getHeroInfoByName"  parameterType="java.lang.String" resultMap="heroResultMap">
            select id,name from herotable  where name like CONCAT('%',#{name},'%')
        </select>
    
        <update id="updateHeroInfo" parameterType="com.wmj.springbootMybatis.Entity.Hero">
            update herotable
            <set >
                <if test="name != null" >
                    name = #{name},
                </if>
            </set>
            where id = #{id}
        </update>
    
        <select id="getMaxHeroId"  parameterType="java.lang.Integer" resultType="java.lang.Integer">
            select Max(id) from herotable
        </select>
    
        <insert id="addHeroInfo" parameterType="com.wmj.springbootMybatis.Entity.Hero" >
            insert into herotable values (#{id}, #{name})
        </insert>
    
        <delete id="deleteHeroInfo" parameterType="java.lang.Integer" >
            delete from herotable
            where id = #{id}
        </delete>
    </mapper>

**    5.4 Service层接口**

package com.wmj.springbootMybatis.Service;
    
    import com.wmj.springbootMybatis.Entity.Hero;
    
    import java.util.List;
    
    public interface HeroService { 
        //获取所有hero
        public List<Hero> getAllHeroInfo();
        //根据id获取hero，返回List
        public List<Hero> getStudentInfoById(int id);
        //根据name获取hero，返回List
        public List<Hero> getStudentInfoByName(String name);
        //修改Hero信息
        int updateHeroInfo(Hero heroInfo);
        //获取hero的最大Id
        int getMaxHeroId();
        //添加Hero信息
        int addHeroInfo(Hero heroInfo);
        //根据id删除Hero信息
        int deleteHeroInfo(Integer id);
    }

**    5.5 Service层实现层**

package com.wmj.springbootMybatis.Service.Impl;
    
    import com.wmj.springbootMybatis.Dao.HeroDao;
    import com.wmj.springbootMybatis.Entity.Hero;
    import com.wmj.springbootMybatis.Service.HeroService;
    import org.springframework.stereotype.Service;
    
    import javax.annotation.Resource;
    import java.util.List;
    
    @Service("heroService")
    public class HeroServiceImpl implements HeroService { 
        @Resource
        private HeroDao heroDao;
    
        @Override
        public List<Hero> getAllHeroInfo() {
            List<Hero> stuInfo =this.heroDao.getAllHeroInfo();
            return stuInfo;
        }
    
        @Override
        public List<Hero> getStudentInfoById(int id) {
            List<Hero> stuInfo =this.heroDao.getHeroInfoById(id);
            return stuInfo;
        }
    
        @Override
        public List<Hero> getStudentInfoByName(String name) {
            List<Hero> stuInfo =this.heroDao.getHeroInfoByName(name);
            return stuInfo;
        }
    
        @Override
        public int updateHeroInfo(Hero heroInfo) {
            return this.heroDao.updateHeroInfo(heroInfo);
        }
    
    
        @Override
        public int getMaxHeroId() {
            return this.heroDao.getMaxHeroId();
        }
    
        @Override
        public int addHeroInfo(Hero heroInfo) {
            return this.heroDao.addHeroInfo(heroInfo);
        }
    
        @Override
        public int deleteHeroInfo(Integer id) {
            return this.heroDao.deleteHeroInfo(id);
        }
    }

**    5.6 Service层实现层**

package com.wmj.springbootMybatis.Controller;
    
    import com.wmj.springbootMybatis.Entity.Hero;
    import com.wmj.springbootMybatis.Service.HeroService;
    import net.sf.json.JSONObject;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RestController;
    
    import javax.annotation.Resource;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    import java.util.ArrayList;
    import java.util.List;
    
    @RestController
    @RequestMapping("/hero")
    public class HeroInfoController {
    
        @Resource
        private HeroService heroSerive;
    
        @RequestMapping(value="/selectAllHero")
        public List<Hero> selectAllHero(HttpServletRequest request, HttpServletResponse response){
            response.setHeader("Access-Control-Allow-Origin", "*"); //解决跨域问题
            List<Hero> allHeroInfo=heroSerive.getAllHeroInfo();
            return allHeroInfo;
        }
    
        @RequestMapping(value="/selectHeroById")
        public List<Hero> selectHeroById(HttpServletRequest request, HttpServletResponse response,String heroId){
            response.setHeader("Access-Control-Allow-Origin", "*");
            List<Hero> HeroInfo=heroSerive.getStudentInfoById(Integer.parseInt(heroId));
            return HeroInfo;
        }
    
        @RequestMapping(value="/selectHeroByName")
        public List<Hero> selectHeroByName(HttpServletRequest request, HttpServletResponse response,String heroName){
            response.setHeader("Access-Control-Allow-Origin", "*");
            List<Hero> HeroInfo = new ArrayList<Hero>();
            if(heroName.equals("")){
    
            }
            else{
                HeroInfo=heroSerive.getStudentInfoByName(heroName);
            }
            return HeroInfo;
        }
    
        @RequestMapping(value="updateHeroById")
        public JSONObject  updateStudentInfo(HttpServletRequest request, HttpServletResponse response, String hero) {
            response.setHeader("Access-Control-Allow-Origin", "*");
            JSONObject jsonobject = JSONObject.fromObject(hero);
            Hero rule = (Hero) JSONObject.toBean(jsonobject, Hero.class);
            int result = heroSerive.updateHeroInfo(rule);
            JSONObject state = new JSONObject();
            if(result ==1){
                state.put("state", "修改成功");
            }
            else{
                state.put("state", "修改失败");
            }
            return state;
        }
        @RequestMapping(value="/addHeroInfo")
        public List<Hero> addStudentInfo(HttpServletRequest request, HttpServletResponse response, String name){
            response.setHeader("Access-Control-Allow-Origin", "*");
    //        JSONObject jsonobject = JSONObject.fromObject(json);
            //获取英雄的最大ID
            int heroMaxId = heroSerive.getMaxHeroId();
            int heroId = heroMaxId+1;
    
            JSONObject heroInfo = new JSONObject();
            heroInfo.put("id", heroId);
            heroInfo.put("name", name);
    
            Hero rule = (Hero) JSONObject.toBean(heroInfo, Hero.class);
            heroSerive.addHeroInfo(rule);
            List<Hero> HeroInfo=heroSerive.getStudentInfoById(heroId);
            return HeroInfo;
    
    
        }
        @RequestMapping(value="deleteHeroById")
        public JSONObject deleteHeroById(HttpServletRequest request, HttpServletResponse response, String  id) {
            response.setHeader("Access-Control-Allow-Origin", "*");
            int result = heroSerive.deleteHeroInfo(Integer.parseInt(id) );
    
            JSONObject state = new JSONObject();
            if(result ==1){
                state.put("state", "删除成功");
            }
            else{
                state.put("state", "删除失败");
            }
            return state;
        }
    }

#### 6. 运行结果 ####

![这里写图片描述][70 9]

[70]: /images/20210726/f4cce666e85e4f77b689abebe3aa56c2.png
[70 1]: /images/20210726/260dc3262f37476c90487686d79f9aca.png
[70 2]: /images/20210726/d7ab49ce49e24be2b38be9ac8e7bc1a3.png
[70 3]: /images/20210726/309970c35d834bf5b1ed4176b4f27237.png
[70 4]: /images/20210726/80224318c06b43a6bb09ce4025800aa9.png
[70 5]: /images/20210726/0883f39a8b824f92b582757d250c04aa.png
[70 6]: /images/20210726/03faeaca5b834640b25ebef57ac95d93.png
[70 7]: /images/20210726/2b2cfaa689b64f9b89e50d6889ce3756.png
[70 8]: /images/20210726/100ffa15b388469d945470e61e3f1f82.png
[70 9]: /images/20210726/3e9ced9a8cf94056ae73c7b6774cc678.png