【mybatis】【第一个Helloworld】【控制台显示sql】

使用的包

domain类

public class User implements Serializable{
    private Long id;
    private String name;
    private Integer age            =(int)(Math.random()*20);
    private Date birthday          =new Date();
    }

配置文件mybatis-config.xml

1.给domain类声明别名
2.部署环境(数据库)
3.引入映射文件

<configuration>
    
    <typeAliases>
        <typeAlias type="com.lwf.mybatis.hallo.User" alias="User"/>
    typeAliases>

    
    
    <environments default="default">
        <environment id="default">
            
            <transactionManager type="JDBC"/>
            
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql:///jdbc"/>
                <property name="username" value="root"/>
                <property name="password" value="admin"/>
            dataSource>
        environment>
    environments> 

    
    <mappers>
        <mapper resource="com/lwf/mybatis/hallo/UserMapper.xml"/>
    mappers>

configuration>

映射文件UserMapper.xml

• 声明属性和列的对应
• sql语句声明

<mapper namespace="com.lwf.mybatis.hallo.UserMapper">
    
    <resultMap type="User" id="user_mapping">
        <id column="id" property="id"/>
        <result column="name" property="name"/>
        <result column="age" property="age"/>
        <result column="birthday" property="birthday"/>
    resultMap>
    

    
    <insert id="add" keyColumn="id" keyProperty="id" useGeneratedKeys="true" parameterType="User">
        insert into user(name,age,birthday) values ( #{name},#{age},#{birthday})    
    insert>

mapper>

结果测试

    @Test
    public void dowork() throws Exception{
        User user = new User();
        //启动框架,获取SqlSessionFactory 
        SqlSessionFactory sf=new SqlSessionFactoryBuilder().
                build(Resources.getResourceAsStream("mybatis-config.xml"));
        //创建session对象(同时也是开启事务)
        SqlSession session = sf.openSession();
        session.insert("com.lwf.mybatis.hallo.UserMapper.add",new User());
        //提交事务,关闭session
        session.commit();
        session.close();

    }

控制台显示sql

在根目录中添加log4j.properties文件

log4j.rootLogger=ERROR, stdout
#表示映射文件的包,所在的位置(是包!是包!是包的位置)
log4j.logger.com.lwf.mybatis=TRACE

log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%5p [%t] - %m%n