IDEA 建Mybatis项目

1.项目结构

2.依赖包(pom.xml)

<dependencies>
    <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis</artifactId>
        <version>3.3.0</version>
    </dependency>
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.29</version>
    </dependency>
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.11</version>
        <scope>test</scope>
    </dependency>
  <dependency>
        <groupId>log4j</groupId>
        <artifactId>log4j</artifactId>
        <version>1.2.17</version>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-api</artifactId>
        <version>1.7.12</version>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-log4j12</artifactId>
        <version>1.7.12</version>
    </dependency>
</dependencies>

3.配置jdbc参数(db.properties)

driver=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/mybatis
username=root
password=root

4.建Bean（Person.java）

package com.xfishs.pojo;

import lombok.Data;
import lombok.ToString;

@Data  //生成get set方法
@ToString //生成toString方法
public class Person {

        private int id;
        private String name ;
        private int age ;

}

　　

5.配置mybatis的配置文件（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">
<configuration>
    <!-- 引入数据库连接配置 -->
    <properties resource="db.properties"/>

    <!-- 定义别名 -->
    <typeAliases>
        <!-- 方式一  、直接定义 -->
        <typeAlias type="com.xfishs.pojo.Person" alias="Person"/>

        <!-- 方式二、 定义包名 -->
        <!--<package name="com.xfishs.pojo" />-->
    </typeAliases>

    <!--定义数据源-->
    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <property name="driver" value="${driver}"/>
                <property name="url" value="${url}"/>
                <property name="username" value="${username}"/>
                <property name="password" value="${password}"/>
            </dataSource>
        </environment>
    </environments>

    <!--定义映射文件-->
    <mappers>
        <mapper resource="mapper/Person.xml"/>
    </mappers>
</configuration>

6.创建mybatis工具类（MyBatisUtil.java）

package com.xfishs.utils;

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.IOException;
import java.io.Reader;

public class MybatisUtil {

    private static SqlSessionFactory sqlSessionFactory = null;

    static {
        try {
            Reader reader = Resources.getResourceAsReader("mybatis-config.xml");
            sqlSessionFactory= new SqlSessionFactoryBuilder().build(reader);
        } catch (IOException e) {
            e.printStackTrace();
        }

    }

    //采用单例模式，私有化构造方法
    private MybatisUtil(){}

    public static SqlSession getSqlSession(){
        return sqlSessionFactory.openSession();
    }

}

　　7.配置mapper（Person.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">
<!-- namespace 对应接口类 -->
<mapper namespace="com.xfishs.dao.PersonMapper">

    <!-- statement -->
    <!--<insert id="insertPerson" parameterType="Person" >-->
        <!--insert into person(name,age) values (#{name},#{age})-->
    <!--</insert>-->

    <!-- id 对应接口的方法名 parameterType 参数类型， resultType 返回值类型-->
    <select id="selectPerson" parameterType="int" resultType="Person">
        SELECT * FROM PERSON WHERE ID=#{id}
    </select>

</mapper>

8.log4j配置文件（log4j.properties）

log4j.rootLogger=debug, stdout, R

log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout

log4j.appender.stdout.layout.ConversionPattern=%5p - %m%n

log4j.appender.R=org.apache.log4j.RollingFileAppender
log4j.appender.R.File=firestorm.log

log4j.appender.R.MaxFileSize=100KB
log4j.appender.R.MaxBackupIndex=1

log4j.appender.R.layout=org.apache.log4j.PatternLayout
log4j.appender.R.layout.ConversionPattern=%p %t %c - %m%n

log4j.logger.com.codefutures=DEBUG

9.进行单元测试（Test）

package com.xfishs.dao;

import com.xfishs.pojo.Person;
import com.xfishs.utils.MybatisUtil;
import org.apache.ibatis.session.SqlSession;
import org.junit.Test;

import static org.junit.Assert.*;

public class PersonMapperTest {

    @Test
    public void selectPerson() {
        SqlSession sqlSession = MybatisUtil.getSqlSession();
        PersonMapper personMapper = sqlSession.getMapper(PersonMapper.class);
        Person person = personMapper.selectPerson(1);
        System.out.println(person);
        sqlSession.close();
    }
}

　　10.测试结果