(mybatis注意各个文件的映射问题)
用到的t_user数据库脚本：
-- 导出 mybatis 的数据库结构
CREATE DATABASE IF NOT EXISTS `mybatis` /*!40100 DEFAULT CHARACTER SET utf8 */;
USE `mybatis`;
-- 导出 表 mybatis.t_user 结构
CREATE TABLE IF NOT EXISTS `t_user` (
`id` int(10) NOT NULL AUTO_INCREMENT,
`username` varchar(50) DEFAULT NULL,
`password` varchar(50) DEFAULT NULL,
`nickname` varchar(50) DEFAULT NULL,
`type` tinyint(4) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;
MyBatisUtil助手类
package edu.hhxy.btais.util;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;public class MyBatisUtil {
private static SqlSession session = null;public static SqlSession createSeqSession() {
try {
// 1、创建配置文件(mybatis-config.xml)的输入流
InputStream is = Resources
.getResourceAsStream("mybatis-config.xml");
// 2、创建SQLSessionFactory
SqlSessionFactory factory = new SqlSessionFactoryBuilder()
.build(is);
// 3、创建SQLSessioin
session = factory.openSession();
} catch (IOException e) {
e.printStackTrace();
}
return session;
}public static void closeSeqSession(SqlSession sqlSession) {
try {
sqlSession.close();
} catch (Exception e) {
e.printStackTrace();
} finally {
sqlSession = null;
}
}
}
User.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 namespace="edu.hhxy.btais.User">
<insert id="add" parameterType="User">
insert into t_user
(username,password,nickname,type)
value(#{username},#{password},#{nickname},#{type})
</insert>
<update id="update" parameterType="User">
update t_user set
password=#{password},nickname=#{nickname},type=#{type} where id=#{id}
</update>
<delete id="delete" parameterType="int">
delete from t_user where
id=#{id}
</delete>
<select id="load" parameterType="int" resultType="User">
select * from
t_user where id=#{id}
</select><select id="list" resultType="User">
select * from t_user
</select>
</mapper>
src/jdbc.properties
username=root
password=root
url=jdbc:mysql://localhost:3306/mybatis
driver=com.mysql.jdbc.Driver
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>
<properties resource="jdbc.properties" />
<typeAliases>
<!--把edu.hhxy.btaisUser类都自动映射为User -->
<typeAlias type="edu.hhxy.btais.User" alias="User" />
<!-- 把edu.hhxy.btais所有类都自动映射 -->
<package name="edu.hhxy.btais" />
</typeAliases>
<!-- 在properties之后加上typeAliases -->
<environments default="development">
<environment id="development">
<transactionManager type="JDBC" />
<!-- 配置mybatis的pooled的数据源 -->
<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>
<mappers>
<mapper resource="edu/hhxy/btais/User.xml" />
</mappers>
</configuration>
FirstMybatisTest.java（JUNIT测试）
package edu.hhxy.btais;import java.util.List;
import org.apache.ibatis.session.SqlSession;
import org.junit.Test;
import edu.hhxy.btais.util.MyBatisUtil;public class FirstMybatisTest {
@Test
public void TestAll() {
addTest();
updateTest();
deleteTest();
loadTest();
listTest();
}@Test
public void addTest() {
SqlSession session = null;
try {
session = MyBatisUtil.createSeqSession();
User u = new User();
for (int i = 0; i < 10; i++) {
u.setNickname("孙悟空");
u.setPassword("123");
u.setType(0);
u.setUsername("wukong");
session.insert("edu.hhxy.btais.User.add", u);
}
session.commit();
} catch (Exception e) {
e.printStackTrace();
} finally {
MyBatisUtil.closeSeqSession(session);
}
}@Test
public void updateTest() {
SqlSession session = null;
try {
session = MyBatisUtil.createSeqSession();
User u = new User();
u.setNickname("齐天大圣孙悟空");
u.setPassword("123");
u.setType(0);
u.setId(106);
u.setUsername("wukong");
session.update("edu.hhxy.btais.User.update", u);
session.commit();
} catch (Exception e) {
e.printStackTrace();
} finally {
MyBatisUtil.closeSeqSession(session);
}
}@Test
public void deleteTest() {
SqlSession session = null;
try {
session = MyBatisUtil.createSeqSession();
User u = new User();
u.setId(105);
session.delete("edu.hhxy.btais.User.delete", u);
session.commit();
} catch (Exception e) {
e.printStackTrace();
} finally {
MyBatisUtil.closeSeqSession(session);
}
}@Test
public void loadTest() {
SqlSession session = null;
try {
session = MyBatisUtil.createSeqSession();
User u = (User) session.selectOne(User.class.getName() + ".load",
5);
System.out.println(u.toString());
} catch (Exception e) {
e.printStackTrace();
} finally {
MyBatisUtil.closeSeqSession(session);
}
}@Test
public void listTest() {
SqlSession session = null;
try {
session = MyBatisUtil.createSeqSession();
List<User> us = session.selectList(User.class.getName() + ".list",
null);
System.out.println(us.size());
} catch (Exception e) {
e.printStackTrace();
} finally {
MyBatisUtil.closeSeqSession(session);
}
}
}
运行FirstMybatisTest.java之前，数据库
运行junit
运行后数据库
源代码下载：http://download.csdn.net/detail/chenwei1510347223/7331529
mybatis(单表增删改查),布布扣,bubuko.com