Mybatis第一个项目尝试（附代码）

一、项目布局如下：

我在mysql数据库创建的数据库名为：mybatis

在mybatis创建了一个表，名为users

二、sql文件users.sql内容如下：

DROP TABLE IF EXISTS `users`;
CREATE TABLE `users` (
`uid` int(11) NOT NULL AUTO_INCREMENT,
`username` varchar(255) DEFAULT NULL,
`password` varchar(255) DEFAULT NULL,
PRIMARY KEY (`uid`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;

INSERT INTO `users` VALUES ('1', 'zhangsan', '123456');
INSERT INTO `users` VALUES ('2', 'lisi', '123456');
INSERT INTO `users` VALUES ('3', 'wangwu', '123456');
INSERT INTO `users` VALUES ('4', 'zhaoliiu', '123456');
INSERT INTO `users` VALUES ('5', 'zhuqi', '123456');

三、项目源代码（mybatis 与jdbc jar 包请自己下载）

1、mybatis主配置文件 mybatisConfig.xml内容如下：

<?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>
<typeAlias type="entity.User" alias="users" />
</typeAliases>
<environments default="development">
<environment id="development">
<transactionManager type="JDBC"></transactionManager>
<dataSource type="POOLED">
<property name="driver" value="com.mysql.cj.jdbc.Driver" />

<property name="url"
value="jdbc:mysql://127.0.0.1:3306/mybatis?useSSL=FALSE&serverTimezone=UTC&useUnicode=true&characterEncoding=utf8" />
<property name="username" value="root" />
<property name="password" value="luhe19971011" />
</dataSource>
</environment>
</environments>
<mappers>
<mapper resource="mapper/userMapper.xml" />
</mappers>
</configuration>

2、映射文件userMapper.xml内容如下

<?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="User">
   <resultMap type="entity.User" id="UserResult">
   <id column="uid" javaType="Integer" property="uid"></id>
   <result column="username" jdbcType="VARCHAR" property="username"></result>
   <result column="password" jdbcType="VARCHAR" property="password"></result>
   </resultMap>
<select id="queryAllUser" resultMap="UserResult">
   select uid, username,password from users where 1=1
</select>
</mapper>

3、数据库访问链接类 dbUtil.java如下

package dbUtil;

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 dbUtil {
private static final String CONFIG_PATH = "config/mybatisConfig.xml";

   /*
   * 获取数据库访问链接
   */
   public static SqlSession getSqlSession() {
       SqlSession session = null;
       try {
           InputStream stream = Resources.getResourceAsStream(CONFIG_PATH);
           // 可以根据配置的相应环境读取相应的数据库环境
           // SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(
           // stream, "development");
           SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(stream);
           session = factory.openSession();
       } catch (Exception e) {
           e.printStackTrace();
       }
       return session;
   }

   /*
   * 获取数据库访问链接
   */
   public static void closeSession(SqlSession session) {
       session.close();
   }
}
4、实体类User.java内容如下：

package entity;

public class User {
   private int uid;
   private String username;
   private String password;
   public int getUid() {
       return uid;
   }
   public void setUid(int uid) {
       this.uid = uid;
   }
   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;
   }
   @Override
   public String toString() {
       return "User [uid=" + uid + ", username=" + username + ", password=" + password + "]";
   }


}
5、测试类testMybatis.java

package test;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import entity.User;
import org.apache.ibatis.session.SqlSession;

import dbUtil.dbUtil;

public class testMybatis {

public static void main(String[] args) throws IOException {
SqlSession session=null;
List<User> list=new ArrayList<User>();
session=dbUtil.getSqlSession();
list=session.selectList("User.queryAllUser");
for(User user:list) {
System.out.println(user);
}
}
}
四、测试类运行结果如下：

Mybatis第一个项目尝试（附代码）

猜你喜欢