java mybatis 入门

1.依赖

2.config配置SqlMapConfig.xml

  链接mysql 8.0驱动：

<property name="driver" value="com.mysql.cj.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://localhost:3306/test?serverTimezone=GMT%2B8"/>

其它版本驱动

<property name="driver" value="com.mysql.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://localhost:3306/test"/>

3.mapper配置IStudentDao.xml

4.使用sessin

 

package com.test.dao;

import com.test.domain.Student;

import java.io.Serializable;
import java.util.List;

public interface IStudentDao  {
    List<Student> findAll();
    Student findBySno(String sno);

    void insert(Student stu);
    void update(Student stu);
}

package com.test.domain;

public class Student {
    String sno;
    String sname;

    public String getSno() {
        return sno;
    }

    public void setSno(String sno) {
        this.sno = sno;
    }

    public String getSname() {
        return sname;
    }

    public void setSname(String sname) {
        this.sname = sname;
    }

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

 

<dependencies>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.13</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.4.5</version>
        </dependency>
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.12</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.10</version>
        </dependency>
    </dependencies>

<?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>
    <!--   配置环境-->
    <environments default="mysql">
        <!--配置mysql的环境-->
        <environment id="mysql">
            <!--配置事务的类型-->
            <transactionManager type="JDBC"></transactionManager>
            <!--配置连接池-->
            <dataSource type="POOLED">
                <!--配置连接数据库的4个基本信息-->
                <property name="driver" value="com.mysql.cj.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://localhost:3306/test?serverTimezone=GMT%2B8"/>
                <property name="username" value="root"/>
                <property name="password" value="ruiFEN@520"/>
            </dataSource>
        </environment>
    </environments>

    <!--指定映射配置文件的位置，映射配置文件指的是每个dao独立的配置文件-->
    <mappers>
        <mapper resource="com.test.dao.IStudentDao.xml"/>
    </mappers>
</configuration>

<?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.test.dao.IStudentDao">
    <select id="findAll"  resultType="com.test.domain.Student">
     select * from student
    </select>
    <select id="findBySno" parameterType="String" resultType="com.test.domain.Student">
     select * from student where sno = #{sno}
    </select>
    <insert id="insert" parameterType="com.test.domain.Student">
        insert into student(sno,sname) values(#{sno},#{sname})
    </insert>
    <insert id="update" parameterType="com.test.domain.Student">
        update student set sname=#{sname} where sno = #{sno}
    </insert>
</mapper>

package com.test.main;

import com.test.domain.Student;
import org.apache.ibatis.io.Resources;
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;
import java.util.Map;

public class main {
    public static void main(String[] args) throws Exception {
        //加载核心文件
        String resource = "sqlMapConfig.xml";
        InputStream resourceAsStream = Resources.getResourceAsStream(resource);
        //创建sqlSessionFactory
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(resourceAsStream);
        //创建sqlSession
        SqlSession session = sqlSessionFactory.openSession();
        //执行sql语句
//        List<Student> list = session.selectList("findAll");
//        for (Student student : list) {
//            System.out.println(student);
//        }
//
//        Student student = session.selectOne("findBySno", "001");
//        System.out.println(student);
//
//        Student stu = new Student();
//        stu.setSno("003");
//        stu.setSname("a333");
//
//        session.insert("insert",stu);
        //session.commit();

        Student stu2 = new Student();
        stu2.setSno("003");
        stu2.setSname("a33333333333");
        session.insert("update",stu2);
        session.commit();

        List<Student> list = session.selectList("findAll");
        for (Student t : list) {
            System.out.println(t);
        }
    }
}