Environment: IDEA MySQL

1. Build maven project, import coordinates: edit pom.xml, and create mybatis constraint.

stay https://mybatis.org/mybatis-3/zh/getting-started.html View the latest version of mybatis and the beginning of the constraint.

<!-- x.x.x by mybaits Version number -->
<dependency>
  <groupId>org.mybatis</groupId>
  <artifactId>mybatis</artifactId>
  <version>x.x.x</version>
</dependency>

Using in mysql

mysql> show variables like "%version%";

Check your MySQL version.

<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.lymMybits</groupId>
    <artifactId>Mybits_first</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>jar</packaging>
    <dependencies>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.3</version>
            <!-- Location MyBatis -->
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.18</version>
            <!-- Location MySQL -->
        </dependency>
    </dependencies>
</project>

2. Create entity class and dao interface.

Entity class User:

package com.Mybaits_test.domain;

import java.io.Serializable;

/**
 * @author  North Cang
 *User Entity class
 */
public class User implements Serializable {
    private Integer ID;
    private String name;
    private  String password;
    private  String sex;
    private String work;
    //Same as column name in table
    public Integer getID() {
        return ID;
    }

    public void setID(Integer ID) {
        this.ID = ID;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getSex() {
        return sex;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }

    public String getWork() {
        return work;
    }

    public void setWork(String work) {
        this.work = work;
    }

    @Override
    public String toString() {
        return "User{" +
                "ID=" + ID +
                ", name='" + name + '\'' +
                ", password='" + password + '\'' +
                ", sex='" + sex + '\'' +
                ", work='" + work + '\'' +
                '}';
    }
}

DAO interface:

package com.Mybaits_test.Dao;

import com.Mybaits_test.domain.User;

import java.util.List;

/**
 * @author North Cang
 * dao Persistence layer interface
 */
public interface IF_UserDao {
    List<User> findAll();
} 

3. Create the main configuration file of Mybatis: SQLMapConifg.xml, and create the mapping configuration file IF_UesDao.xml.

Note the constraints of Conifg and Mapper:

Constraints for Conifg:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration  
  PUBLIC "-//mybatis.org//DTD Config 3.0//EN"  
  "http://mybatis.org/dtd/mybatis-3-config.dtd">

Mapper constraints:

<?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">

Main configuration file: create SQLMapConifg.xml under resource, and establish the constraint of Conifg.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<!-- Master profile -->
<configuration>
    <!-- Environmental configuration -->
    <environments default="mysql">
        <!-- mysql Environmental configuration -->
        <environment id="mysql">
            <!-- Configure the type of things -->
            <transactionManager type="JDBC"></transactionManager>
            <!-- Configure connection pool -->
            <dataSource type="POOLED">
                <!-- Configure connection information to connect to the database -->
                <property name="driver" value="com.mysql.cj.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://localhost:3306/test.jdbc?serverTimezone=GMT%2B8"/>
                <property name="username" value="root"/>
                <property name="password" value="123456"/>
            </dataSource>
        </environment>
    </environments>

    <!-- Specifies the location of the mapping profile, which is each DAO Class independent profile -->
    <mappers>
        <mapper resource="com/Mybaits_test/dao/IF_UesDao.xml"/>
    </mappers>
</configuration>

Create and create the COM / mybaits · test / Dao folder under resource, map the configuration file if · uesdao.xml, and create the Mapper constraint.

<?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.Mybaits_test.Dao.IF_UserDao">
    <select id="findAll">
        select * from  user
    </select>
</mapper>