简介

Mybatis是现在十分流行的数据持久化框架，这次就来用SpringBoot来整合使用Mybatis。

依赖

  <dependencies>
		<!-- Mybatis场景启动器 -->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.1.1</version>
        </dependency>
		<!-- web场景启动器 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
		<!-- MySQL驱动 -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
		<!-- Druid -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.2.1</version>
        </dependency>
		<!-- log4j日志 -->
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.17</version>
        </dependency>
		<!-- lombok -->
         <dependency>
             <groupId>org.projectlombok</groupId>
             <artifactId>lombok</artifactId>
         </dependency>
		<!-- 单元测试 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>
    <build>
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.xml</include>
                </includes>
                <filtering>true</filtering>
            </resource>
        </resources>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

定义实体类

package com.yww.pojo;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;


@Data
@NoArgsConstructor
@AllArgsConstructor
public class User {
    
    int ID;
    
    String name;
    
}

定义Mapper接口

package com.yww.mapper;
import com.yww.pojo.User;
import org.apache.ibatis.annotations.Mapper;
import org.springframework.stereotype.Repository;
import java.util.List;

@Mapper
@Repository
public interface UserMapper {
    
    List<User> selectUserList();
    
    User selectUserByID(int ID);
    
    int addUser(User user);
    
    int updateUser(User user);
    
    int deleteUser(int id);
    
}

创建Mybatis配置文件

<?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">
	<!--绑定mapper接口，位置要写对-->
<mapper namespace="com.yww.mapper.UserMapper">
    
    <select id="selectUserList" resultType="User">
        SELECT * FROM user
    </select>

    <select id="selectUserByID" resultType="User">
        SELECT * FROM user WHERE ID = #{ID}
    </select>

    <insert id="addUser" parameterType="User">
        INSERT INTO user (ID,name) VALUES (#{ID},#{name})
    </insert>

    <update id="updateUser" parameterType="User">
        UPDATE user SET name=#{name} WHERE ID = #{ID}
    </update>

    <delete id="deleteUser" parameterType="int">
        DELETE FROM user WHERE ID=#{ID}
    </delete>
    
</mapper>

配置SpringBoot配置文件

# application.yml使用
# 连接数据库
spring:
  datasource:
    username: root
    password: password
    url: jdbc:mysql://localhost:3306/test?userUnicode=true&characterEncoding=utf-8&serverTimezone=UTC
    driver-class-name: com.mysql.cj.jdbc.Driver
    type: com.alibaba.druid.pool.DruidDataSource	
    # Druid的配置
    initialSize: 5
    minIdle: 5
    maxActive: 20
    max-wait: 60000
    timeBetweenEvictionRunsMillis: 60000
    minEvictableIdleTimeMillis: 300000
    validationQuery: SELECT 1 FROM DUAL
    testWhileIdle: true
    testOnBorrow: false
    testOnReturn: false
    poolPreparedStatements: true
    filters: stat,wall,log4j
    maxPoolPreparedStatementPerConnectionSize: 20
    useGlobalDataSourceStat: true
    connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=500
# mybatis设置
mybatis:
  type-aliases-package: com.yww.pojo					#绑定实体类，不然配置文件识别不出User
  mapper-locations: classpath:mybatis/mapper/*.xml		#绑定mybatis的配置文件

编写controller

package com.yww.controller;

import com.yww.mapper.UserMapper;
import com.yww.pojo.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import java.util.List;
@RestController
public class UserController {
    
    @Autowired
    private UserMapper userMapper;
    
    @GetMapping("/select")
    public List<User> selectUserList(){
        List<User> list = userMapper.selectUserList();
        return list;
    }
    
    @GetMapping("/selectbyid")
    public User selectByID(){
        User user = userMapper.selectUserByID(1);
        return user;
    }
    
    @GetMapping("/insert")
    public int addUser(){
        User user = new User(3, "王五");
        return  userMapper.addUser(user);
    }
    
    @GetMapping("/update")
    public int  updateUser(){
        User user = new User(3, "赵六");
        return userMapper.updateUser(user);
    }
    
    @GetMapping("/delete")
    public int  deleteUser(){
        return userMapper.deleteUser(3);
    }
    
}