mybatis开发环境配置

1需要用到的包：

mybatis-3.1.1.jar

log4j-1.2.15.jar 当然还有 mysql 的驱动包

2建立数据表：

CREATE TABLE `user` (
   `userId` int(11) NOT NULL AUTO_INCREMENT,
   `userName` varchar(50) DEFAULT NULL,
   `password` varchar(50) DEFAULT NULL,
   `comment` varchar(1000) DEFAULT NULL,
   PRIMARY KEY (`userId`)
 ) ENGINE=InnoDB AUTO_INCREMENT=8 DEFAULT CHARSET=utf8

3规划好你项目的结构

com.seatno.log4j 为我的 日志测试类

4:数据实体User

package com.seatno.entity;
public class User {
    private String userId;
    private String userName;
    private String password;
    private String comment;
    public String getUserId() {
        return userId;
    }
    public void setUserId(String userId) {
        this.userId = userId;
    }
    public String getUserName() {
        return userName;
    }
    public void setUserName(String userName) {
        this.userName = userName;
    }
    public String getPassword() {
        return password;
    }
    public void setPassword(String password) {
        this.password = password;
    }
    public String getComment() {
        return comment;
    }
    public void setComment(String comment) {
        this.comment = comment;
    }
}

5:写DAO层接口

package com.seatno.dao;
import java.util.List;
import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Select;
import com.seatno.entity.User;
public interface UserDao {
    public int insert(User user);
    public int update(User user);
    public int delete(String userName);
    public List<User> selectAll();
    public int countAll();
    public User findByUserName(String userName); //通过注释方式 绑定SQL 语句
    @Select("SELECT * FROM user WHERE userId = #{userId}")
    User getUser(@Param("userId") String userId);
}

6写mybatis配置文件

文件名任意：我这里取名为MyBatis-Configuration.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>
    <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/study?useUnicode=true&characterEncoding=UTF-8&zeroDateTimeBehavior=convertToNull" />
                <property name="username" value="root" />
                <property name="password" value="123456" />
            </dataSource>
        </environment>
    </environments>
    <mappers>
        <mapper resource="UserDaoMapper.xml"/><!-- 若不直接在src下，需要加入路径，默认根是classpath -->
    </mappers>
 </configuration>

7写SQL映射文件

如果采用注释方式就不需要了，我很喜欢采用注释方式；  

<?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.seatno.dao.UserDao">
    <select id="countAll" resultType="int">
        select count(*) c from user;
    </select>
    <select id="selectAll" resultType="com.seatno.entity.User">
        select * from user order by userName asc
    </select>
    <insert id="insert" parameterType="com.seatno.entity.User">
        insert into user(userName,password,comment) values(#{userName},#{password},#{comment})
    </insert>
    <update id="update" parameterType="com.seatno.entity.User">
        update user set userName=#{userName},password=#{password},comment=#{comment} where userName=#{userName}
    </update>
    <delete id="delete" parameterType="int">
        delete from user where userName=#{userName}
    </delete>
    <select id="findByUserName" parameterType="String" resultType="com.seatno.entity.User">
        select * from user where userName=#{userName}
    </select>
</mapper>

8写个测试类试试 UserDaoTest.java

package com.seatno.dao.impl;
import java.io.Reader;
import java.util.Iterator;
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 org.apache.log4j.Logger;
import org.junit.Test;//添加测试框架类
import com.seatno.dao.UserDao;
import com.seatno.entity.User;
import com.seatno.log4j.log4jTest;

public class UserDaoTest { //添加日志输出，你可以不要， 这个需要配置文件 log4j.properties（放在根目录下面）
    Logger logger = Logger.getLogger(log4jTest.class);
    @Test //表示该类是测试用例函数
    public void userDaoTest() throws Exception
    {
        String resource = "MyBatis-Configuration.xml";
        Reader reader = Resources.getResourceAsReader(resource);
        SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
        SqlSessionFactory factory = builder.build(reader);
        SqlSession session = factory.openSession();
     
      UserDao userDao = session.getMapper(UserDao.class);//这是关键
       //插入数据 2条做测试
        User user = new User();
        user.setUserName("我是建伟");
        user.setPassword("123456");
        user.setComment("我做电子商务");
        userDao.insert(user);
        user.setUserName("jianwei");
        user.setPassword("123456");
        user.setComment("备注建伟");
        userDao.insert(user);
        System.out.println("记录条数："+userDao.countAll());
        //通过userId获取一个对象
        User tUser=userDao.getUser("2");
        System.out.println("getUser:用户名："+tUser.getUserName()+"密码："+tUser.getPassword());
        List<User> users = userDao.selectAll();
        Iterator<User> iter = users.iterator();
        while(iter.hasNext()){
            User u = iter.next();
            System.out.println("用户名："+u.getUserName()+"密码："+u.getPassword());
        }
        //更新数据
        user.setComment("I love you");
        userDao.update(user);
        User u = userDao.findByUserName("jianwei");
        System.out.println(u.getComment()); //通过名称删除数据
        userDao.delete("jianwei");
        System.out.println("记录条数："+userDao.countAll());
        // 提交数据
        session.commit();
        session.close();
    }

}

9, log4j.properties文件

log4j.类库默认使用根（classpath）下的这个文件，如果需要另配文件名需要手动加载这个文件，请参考我的其他文档;

A1,A2,A3 表示定义3个不同的日志输出方式

log4j.rootCategory=INFO,A1,A2,A3
log4j.appender.A1=org.apache.log4j.ConsoleAppender //控制台输出
log4j.appender.A1.layout=org.apache.log4j.PatternLayout
log4j.appender.A1.layout.ConversionPattern=%4p [%t] (%F:%L) - %m%n
log4j.appender.A2=org.apache.log4j.RollingFileAppender

log4j.appender.A2.File=./javalog.log //文件输出 ,表示在项目的根下建立日志文件
log4j.appender.A2.MaxFileSize = 1KB
log4j.appender.A2.MaxBackupIndex = 3 //备份3个文件
log4j.appender.A2.layout=org.apache.log4j.PatternLayout
log4j.appender.A2.layout.ConversionPattern=%d{yyyy-MM-dd hh:mm:ss}:%p %t %c - %m%n

log4j.appender.A3=org.apache.log4j.jdbc.JDBCAppender // 保存到数据库
log4j.appender.A3.URL=jdbc:mysql://localhost:3306/study
log4j.appender.A3.driver=com.mysql.jdbc.Driver
log4j.appender.A3.user=root
log4j.appender.A3.password=123456
log4j.appender.A3.layout=org.apache.log4j.PatternLayout
log4j.appender.A3.layout.ConversionPattern=INSERT INTO log4j(createDate,thread,level,class,message) values(\'%d\',\'%t\',\'%-5p\',\'%c\',\'%m\')
//一下为mybatisSQL 输出
log4j.logger.java.sql.ResultSet=INFO
log4j.logger.org.apache=INFO
log4j.logger.java.sql.Connection=DEBUG
log4j.logger.java.sql.Statement=DEBUG
log4j.logger.java.sql.PreparedStatement=DEBUG