Spring Boot 整合MyBatis的增删改查

旧城等待， 2022-04-17 05:13 309阅读 0赞

## Spring框架非常优秀,但是它最大的问题是每个项目的开发都需要编写大量的配置文件.Spring Boot 的出现就是为了解决Spring框架存在的问题.你可以把它当做Spring MVC的升级版,有Spring MVC方面学习经验的读者可以迅速学会Spring Boot ,因为Spring Boot比Spring MVC简单的不是一点点,让你完全沉浸于业务的思考编码,不用考虑后期繁杂的配置文件维护.并且Spring Boot与Spring Cloud的微服务无缝结合(学习的重要原因之一).用一次就喜欢上了,哈哈! ##

## 因为Spring Boot与Spring MVC惊人相似,可以采用跳跃式的学习方式,这里分享一篇Spring Boot与MyBatis整合实现后端接口增删改查的一小段代码. ##

## 项目的包结构这里使用Maven打包的形式,项目结构图如下: ##

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2xpbmhhaXl1bl95dGR4_size_16_color_FFFFFF_t_70][]

## 配置文件只有application.properties(一些原先Spring的配置文件)和banner.txt(项目的启动图案个人设计) ##

application.properties

#port
    server.port=9999
    # url
    spring.datasource.url=jdbc:mysql://localhost:3306/springboot?useUnicode=true&characterEncoding=utf8
    # username
    spring.datasource.username=root
    # password
    spring.datasource.password=123456
    # driver
    spring.datasource.driver-class-name=com.mysql.jdbc.Driver

banner.txt

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    ██║  ██║██╔════╝██║     ██║     ██╔═══██╗    ██║  ██║██╔══██╗██║██╔════╝ ██╔════╝
    ███████║█████╗  ██║     ██║     ██║   ██║    ███████║███████║██║██║  ███╗█████╗  
    ██╔══██║██╔══╝  ██║     ██║     ██║   ██║    ██╔══██║██╔══██║██║██║   ██║██╔══╝  
    ██║  ██║███████╗███████╗███████╗╚██████╔╝    ██║  ██║██║  ██║██║╚██████╔╝███████╗
    ╚═╝  ╚═╝╚══════╝╚══════╝╚══════╝ ╚═════╝     ╚═╝  ╚═╝╚═╝  ╚═╝╚═╝ ╚═════╝ ╚══════╝

## 接下来是接口的核心代码: ##

package com.weichai.SmTest.entity;
    
    import java.io.Serializable;
    
    public class User implements Serializable {
    
    	private static final long serialVersionUID = 1L;
    
    	private int id;
    	private String loginName;
    	private String username;
    	private String password;
    	public int getId() {
    		return id;
    	}
    	public void setId(int id) {
    		this.id = id;
    	}
    	public String getLoginName() {
    		return loginName;
    	}
    	public void setLoginName(String loginName) {
    		this.loginName = loginName;
    	}
    	public String getUsername() {
    		return username;
    	}
    	public void setUsername(String username) {
    		this.username = username;
    	}
    	public String getPassword() {
    		return password;
    	}
    	public void setPassword(String password) {
    		this.password = password;
    	}
    	
    	
    }

package com.weichai.SmTest.dao;
    
    import java.util.List;
    
    import org.apache.ibatis.annotations.Delete;
    import org.apache.ibatis.annotations.Insert;
    import org.apache.ibatis.annotations.Options;
    import org.apache.ibatis.annotations.Param;
    import org.apache.ibatis.annotations.Result;
    import org.apache.ibatis.annotations.ResultMap;
    import org.apache.ibatis.annotations.Results;
    import org.apache.ibatis.annotations.Select;
    import org.apache.ibatis.annotations.Update;
    
    import com.weichai.SmTest.entity.User;
    
    public interface UserDao {
    
    	@Insert("insert into tb_user(login_name ,username ,password) "
    			+ "values (#{loginName},#{username},#{password})")
    	public void AddUser(User user);
    	
    	/**
    	 * 插入数据获取主键
    	 */
    	@Insert("insert into tb_user(login_name ,username ,password) "
    			+ "values (#{loginName},#{username},#{password})")
    	@Options(useGeneratedKeys=true,keyProperty="id",keyColumn="id")
    	public void insertGetKey(User user);
    	
    	@Select("select * from tb_user where username = #{username}")
    	// 引用id="userResult"的@Results
    	@ResultMap("userResult")
    	public User selectByUsername(@Param("username")String username);
    	
    	@Select("select * from tb_user")
    	// @Results用于映射对象属性和数据库列，常用于对象属性和数据库列不同名情况
    	@Results(id="userResult",value={
    			@Result(id=true,column="id",property="id"),
    			@Result(column="login_name",property="loginName"),
    			@Result(column="password",property="password"),
    			@Result(column="username",property="username")
    		})
    	public List<User> findAll();
    	
    	@Delete("delete from tb_user where id=#{id}")
    	public void delete(final Integer id);
    	
    	@Select("select * from tb_user where id=#{id}")
    	// 引用id="userResult"的@Results
    	@ResultMap("userResult")
    	public User findUserById(int id);
    	
    	@Update("update tb_user set username=#{username}, login_name=#{loginName} where id=#{id}")
    	public void update(final User user);
    }

package com.weichai.SmTest.service;
    
    import java.util.List;
    
    import javax.annotation.Resource;
    
    import org.springframework.stereotype.Service;
    
    import com.weichai.SmTest.dao.UserDao;
    import com.weichai.SmTest.entity.User;
    
    @Service
    public class UserService {
    
    	// 注入UserDao
    	@Resource
    	private UserDao userDao;
    	
    	public void AddUser(User user){
    		userDao.AddUser(user);
    	}
    	
    	public User selectByUsername(String username){
    		return userDao.selectByUsername(username);
    	}
    	
    	public List<User> findAll(){
    		return userDao.findAll();
    	}
    	
    	public void insertGetKey(User user) {
    		// 数据插入成功以后，Mybatis框架会将插入成功的数据主键存入到user对象中去
    		userDao.insertGetKey(user);
    	}
    	
    	public void update(User user) {
    		userDao.update(user);
    	}
    	
    	public void delete(Integer id) {
    		userDao.delete(id);
    	}
    	
    	public User findUserById(int id){
    		return userDao.findUserById(id);
    	}
    }

package com.weichai.SmTest.controller;
    
    import java.util.List;
    
    import javax.annotation.Resource;
    
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RestController;
    
    import com.weichai.SmTest.entity.User;
    import com.weichai.SmTest.service.UserService;
    
    @RestController
    @RequestMapping("/user")
    public class UserController {
    
    	// 注入UserService
    	@Resource
    	private UserService userService;
    	
    	@RequestMapping("/insertUser")
    	public void insertUser(User user){
    		userService.AddUser(user);
    	}
    	
    	@RequestMapping("/insertGetKey")
    	public User insertGetKey(User user) {
    		userService.insertGetKey(user);
    		return user ;
    	}
    	
    	@RequestMapping("/selectByUsername")
    	public User selectByUsername(String username){
    		return userService.selectByUsername(username);
    	}
    	
    	@RequestMapping("/findAll")
    	public List<User> findAll(){
    		return userService.findAll();
    	}
    	
    	@RequestMapping("/update")
    	public void update(User user) {
    		userService.update(user);
    	}
    	
    	@RequestMapping("/delete")
    	public void delete(Integer id) {
    		userService.delete(id);
    	}
    	
    	@RequestMapping("/findUserById")
    	public User findUserById(int id){
    		return userService.findUserById(id);
    	}
    }

## App.java(Spring Boot项目启动类,直接运行即可启动服务) ##

package com.weichai.SmTest;
    
    import org.mybatis.spring.annotation.MapperScan;
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    
    @SpringBootApplication
    //扫描数据访问层接口的包名。
    @MapperScan("com.weichai.SmTest.dao")
    public class App 
    {
        public static void main( String[] args )
        {
        	SpringApplication.run(App.class, args);
        }
    }

## 服务启动后,控制台打印如下: ##

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2xpbmhhaXl1bl95dGR4_size_16_color_FFFFFF_t_70 1][]

## 由于个人设置的端口号是9999,因此直接打开浏览器输入如下链接进行本次项目的测试 ##

http://localhost:9999/user/insertUser?loginName=haige&username=海哥&password=123456
    
    http://localhost:9999/user/insertGetKey?loginName=haige&username=海哥&password=123456
    
    http://localhost:9999/user/selectByUsername?username=海哥
    
    http://localhost:9999/user/findAll
    
    http://localhost:9999/user/update?loginName=xiaozhang&id=2
    
    http://localhost:9999/user/findUserById?id=2

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[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2xpbmhhaXl1bl95dGR4_size_16_color_FFFFFF_t_70 1]: /images/20220417/cc5395d2dc8c467d915c5e27701206db.png