mybatis学习-基础

1、基础回顾

1.1、引入jar包

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

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>5.1.32</version>
</dependency>

1.2、 创建数据库表

CREATE TABLE PERSON(
 id INT(11) PRIMARY KEY AUTO_INCREMENT COMMENT '人员编号',
 `name` NVARCHAR(50) NOT NULL COMMENT '姓名',
 sex NVARCHAR(50) NOT NULL COMMENT '性别',
 age INT(20) NOT NULL COMMENT '年龄',
 rank NVARCHAR(50) NOT NULL COMMENT '等级',
 department NVARCHAR(100) NOT NULL COMMENT '所在部门'
)COMMENT '人员信息表';

INSERT INTO PERSON(id,name,sex,age,rank,department) VALUES(1,'张三','',25,'1级','开发部')；

 1.3、JDBC基础代码回顾

package com.ft.dao;



import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;

import com.mysql.jdbc.Connection;
import com.mysql.jdbc.PreparedStatement;

public class JDBCTest {
    public static void main(String[] args) {
        Connection conn = null;
        PreparedStatement pst = null;
        ResultSet rs = null;
        try {
            Class.forName("com.mysql.jdbc.Driver");
            String url = "jdbc:mysql://127.0.0.1:3306/ssmdemo";
            String user = "root";
            String password = "root";
            conn = (Connection) DriverManager.getConnection(url, user, password);
            String sql  = "select * from person";
            pst = (PreparedStatement) conn.prepareStatement(sql);
            rs = pst.executeQuery();
            while(rs.next()) {
                System.out.print(rs.getString("id"));
                System.out.print(rs.getString("name"));
                System.out.print(rs.getString("sex"));
                System.out.print(rs.getString("age"));
                System.out.print(rs.getString("rank"));
                System.out.println(rs.getString("department"));
            }
            
        }catch (Exception e) {
            // TODO: handle exception
        }
        finally {
            if(rs != null) {
                try {
                    rs.close();
                    pst.close();
                    conn.close();
                } catch (SQLException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
        }
        
    }
    
    
}

1.4、JDBC确定分析

2、MyBatis介绍

 3、MyBatis整体架构

 4、MyBatis快速入门

4.1、全局配置文件（mybatis-config.xml）

<?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">
<!-- 根标签 -->
<configuration>
<properties>
    <property name="driver" value="com.mysql.jdbc.Driver"/>
    <property name="url" value="jdbc:mysql://127.0.0.1:3306/mybatis-110?useUnicode=true&amp;characterEncoding=utf-8&amp;allowMultiQueries=true"/>
    <property name="username" value="root"/>
        <property name="password" value="123456"/>
   </properties>

   <!-- 环境，可以配置多个，default：指定采用哪个环境 -->
   <environments default="test">
      <!-- id：唯一标识 -->
      <environment id="test">
         <!-- 事务管理器，JDBC类型的事务管理器 -->
         <transactionManager type="JDBC" />
         <!-- 数据源，池类型的数据源 -->
         <dataSource type="POOLED">
            <property name="driver" value="com.mysql.jdbc.Driver" />
            <property name="url" value="jdbc:mysql://127.0.0.1:3306/ssmdemo" />
            <property name="username" value="root" />
            <property name="password" value="root" />
         </dataSource>
      </environment>
      <environment id="development">
         <!-- 事务管理器，JDBC类型的事务管理器 -->
         <transactionManager type="JDBC" />
         <!-- 数据源，池类型的数据源 -->
         <dataSource type="POOLED">
            <property name="driver" value="${driver}" /> <!-- 配置了properties，所以可以直接引用 -->
            <property name="url" value="${url}" />
            <property name="username" value="${username}" />
            <property name="password" value="${password}" />
         </dataSource>
      </environment>
   </environments>
   <mappers>
           <mapper resource="mapper/MyMapper.xml"/>
   </mappers>
   
  </configuration>

4.2、 配置Map.xml（MyMapper.xml）

<?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:根标签，namespace：命名空间，随便写，一般保证命名空间唯一 -->
<mapper namespace="MyMapper">
   <!-- statement，内容：sql语句。id：唯一标识，随便写，在同一个命名空间下保持唯一
      resultType：sql语句查询结果集的封装类型,tb_user即为数据库中的表
    -->
   <select id="selectperson" resultType="com.ft.entity.Person">
      select * from person where id = #{id}
   </select>
</mapper>

4.3、目录结构

 4.4、javaBean类

package com.ft.entity;

public class Person {
    private int id;
    private String name;
    private String sex;
    private int age;
    private String rank;
    private String department;
    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;
    }
    public String getSex() {
        return sex;
    }
    public void setSex(String sex) {
        this.sex = sex;
    }
    public int getAge() {
        return age;
    }
    public void setAge(int age) {
        this.age = age;
    }
    public String getRank() {
        return rank;
    }
    public void setRank(String rank) {
        this.rank = rank;
    }
    public String getDepartment() {
        return department;
    }
    public void setDepartment(String department) {
        this.department = department;
    }
    @Override
    public String toString() {
        return "Person [id=" + id + ", name=" + name + ", sex=" + sex + ", age=" + age + ", rank=" + rank
                + ", department=" + department + "]";
    }
    public Person(int id, String name, String sex, int age, String rank, String department) {
        super();
        this.id = id;
        this.name = name;
        this.sex = sex;
        this.age = age;
        this.rank = rank;
        this.department = department;
    }
    public Person() {
        super();
    }
    
}

 4.5、测试代码

package com.ft.dao;

import java.io.IOException;
import java.io.InputStream;

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 com.ft.entity.Person;

public class Mybatistest {
    public static void main(String[] args) throws IOException {
        String resource = "mybatis-config.xml";
        //读取配置文件
        InputStream input = Resources.getResourceAsStream(resource);
        //构建sqlSessionFactory
        SqlSessionFactory sessionFactory = new SqlSessionFactoryBuilder().build(input);
        //获取sqlSession
        SqlSession session = sessionFactory.openSession();
        try {
             Person per = session.selectOne("MyMapper.selectperson", 1);
             System.out.println(per);
        } finally {
            // TODO: handle finally clause
            session.close();
        }
        
        
    }
}