mybatis搭建（单表）

1、导入依赖

点击查看代码

 <!--mybatis-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.2.8</version>
        </dependency>

2、配置mybatis.xml（连接数据库、导入mapper）

点击查看代码

<?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">
<configuration>
    <!--DB的四大步骤-->
    <properties>
        <property name="driver" value="com.mysql.cj.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://127.0.0.1:3306/class?characterEncoding=utf8"/>
        <property name="username" value="root"/>
        <property name="password" value="root"/>
    </properties>
    <environments default="development">
        <environment id="development">
            <transactionManager type="jdbc"></transactionManager>
            <dataSource type="POOLED">
                <property value="${driver}" name="driver"/>
                <property value="${url}" name="url"/>
                <property value="${username}" name="username"/>
                <property value="${password}" name="password"/>
            </dataSource>
        </environment>
    </environments>
<!--导入mapper-->
    <mappers>
    <mapper resource="mapper/StudentMapper.xml"/>
    <!-- <mapper resource="mapper/TableMapper.xml" />-->
    </mappers>
</configuration>

3、建立po实体类

点击查看代码

package com.bh.po;

public class Student {
    private int id;
    private String name;

    public Student() {
    }

    public Student(int id, String name) {
        this.id = id;
        this.name = 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;
    }

    @Override
    public String toString() {
        return "Student{" +
                "id=" + id +
                ", name='" + name + '\'' +
                '}';
    }
}

4、建立DAO接口

点击查看代码

package com.bh.dao;

import com.bh.po.Student;

import java.util.List;

public interface IStudentDAO {
    public List<Student> findAll();
    public int save(Student student);
    public int remove(Student student);
    public int modify(Student student);

}

5、建立mapper.xml

点击查看代码

<?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.bh.dao.IStudentDAO">
    <!--resultType为返回的结果值类型（单表查询使用）-->

    <select resultType="com.bh.po.Student" id="findAll"><!--这里id对应dao接口的方法名-->
        select * from student
    </select>
<!--parameterType为传的参数类型-->
    <insert id="save" parameterType="com.bh.po.Student">
        insert into student values(#{id}, #{name})
    </insert>

    <!-- <delete id="">-->

    <delete id="remove" parameterType="com.bh.po.Student">
        delete from student where id=#{id}
    </delete>

    <update id="modify" parameterType="com.bh.po.Student">
        update student set name=#{name} where id=#{id}
    </update>
    <!-- <update id=""></update>-->


</mapper>

6、测试

点击查看代码

package com.bh.Test;

import com.bh.dao.IStudentDAO;
import com.bh.po.Student;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

import java.io.InputStream;
import java.util.List;

public class Test {
    public static void main(String[] args) {
        System.out.println("start--------");
        //读取配置文件
        InputStream in = Thread.currentThread().getContextClassLoader().getResourceAsStream("mybatis.xml");
        //获取工厂的builder
        SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
        //创建工厂
        SqlSessionFactory sqlSessionFactory = builder.build(in);
        //创建mybatis的sqlSqlsession
        SqlSession sqlSession = sqlSessionFactory.openSession();

        IStudentDAO studentDAO = sqlSession.getMapper(IStudentDAO.class);
       /* List<Student> all = studentDAO.findAll();
        for (int i = 0; i < all.size(); i++) {
            Student stu = all.get(i);
            System.out.println(stu.getId() + "_" + stu.getName());
        }*/
        Student stu = new Student();
        stu.setName("kuan");
        stu.setId(23);
        /*studentDAO.save(stu);*/
        /*studentDAO.modify(stu);*/
        studentDAO.remove(stu);
        sqlSession.commit();
        System.out.println("end---------");
    }
}