mybatis的使用

1.导入jar包

asm-3.3.1.jar
cglib-2.2.2.jar
commons-logging-1.1.1.jar
log4j-1.2.16.jar
mybatis-3.1.1.jar
mysql-connector-java-5.1.10-bin.jar
slf4j-api-1.6.2.jar
slf4j-log4j12-1.6.2.jar

2.创建一个总的配置文件

<?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>
    <typeAliases>
        <!--给实体类起一个别名 user -->
        <typeAlias type="com.kite.mybatis.domain.User" alias="User" />
    </typeAliases>
    <!-- 配置数据源 -->
    <environments default="development">
        <environment id="development">
            <transactionManager type="jdbc" />
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.jdbc.Driver" />
                <property name="url" value="jdbc:mysql://localhost:3306/mybatis" />
                <property name="username" value="root" />
                <property name="password" value="aaa123456" />
            </dataSource>
        </environment>
    </environments>
    <!-- 映射文件也是dao的实现类 -->
    <mappers>
        <mapper resource="com/kite/mybatis/domain/UserMapper.xml" />
    </mappers>
</configuration>

3.创建实体类

package com.kite.mybatis.domain;

public class User
{
    private String id;
    private String name;
    private String age;
    public String getId()
    {
        return id;
    }
    public void setId(String id)
    {
        this.id = id;
    }
    public String getName()
    {
        return name;
    }
    public void setName(String name)
    {
        this.name = name;
    }
    public String getAge()
    {
        return age;
    }
    public void setAge(String age)
    {
        this.age = age;
    }
    
}

4.创建dao类  

package com.kite.mybatis.dao;

import java.util.List;

import com.kite.mybatis.domain.User;

public interface UserMapper
{
    public List<User> selectAll();
}

5.创建user的映射文件  因为要作为userMapper的实现所以在 文件的头部<mapper namespace="com.kite.mybatis.dao.UserMapper"> 必需与dao类对应

<?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.kite.mybatis.dao.UserMapper">
    <select id="selectAll"  resultType="user">
        select * from user
    </select>
</mapper>

6.测试

package com.kite.mybatis.test;

import java.io.IOException;
import java.util.List;

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.kite.mybatis.dao.UserMapper;
import com.kite.mybatis.domain.User;

public class MyBatisTest
{
    public static void main(String[] args) throws IOException
    {
        //记载mybatis的配置文件
        SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(Resources.getResourceAsReader("configuraction.xml"));
        //创建打开sesison
        SqlSession session =  factory.openSession();
        UserMapper userDao = session.getMapper(UserMapper.class);
        List<User> userList = userDao.selectAll();

        System.out.println(userList.size());
    }
}

一个mybatis的简单测试