MyBatis学习——我的第一个MyBatis程序
1、创建maven父集中版本定义工程
工具：myeclipse 2016 CI 7(当初装的测试版)
步骤：File->New->Maven Project
如图，把红色箭头处的选项勾上：
输入，Group id 和Arfact id，
选择红色箭头指的pom，
GroupID 是项目组织唯一的标识符，实际对应JAVA的包的结构，是main目录里java的目录结构。
ArtifactID是项目的唯一的标识符，实际对应项目的名称，就是项目根目录的名称。
修改pom.xml文件，在这看吧：地址
2、创建mybatis项目，（添加 <parent><!-- 引入父工程 --></parent>）
创建过程：略
修改pom.xml
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<!-- 引入父工程 -->
<!-- 版本做了统一管理 出现红×更新 -->
<groupId>com.liantao.parent</groupId>
<artifactId>maven-parent</artifactId>
<version>0.0.1-SNAPSHOT</version>
</parent>
<groupId>com.liantao.mybatis01</groupId>
<artifactId>mybatis01</artifactId>
<version>1.0.1-SNAPSHOT</version>
<dependencies>
<!-- MySql -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<!-- Mybatis -->
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
</dependency>
</dependencies>
<build/>
</project>
添加相关包和相关目录：myeclipse下，右键项目，maven->update Project
3、在mysql下建立数据库ssm,并创建t_user表
DROP TABLE IF EXISTS `t_user`;
CREATE TABLE `t_user` (
`id` bigint(20) NOT NULL AUTO_INCREMENT,
`user_name` varchar(100) DEFAULT NULL COMMENT '用户名',
`password` varchar(100) DEFAULT NULL COMMENT '密码',
`name` varchar(100) DEFAULT NULL COMMENT '姓名',
`age` int(10) DEFAULT NULL COMMENT '年龄',
`sex` tinyint(1) DEFAULT NULL COMMENT '性别，1男性，2女性',
`birthday` date DEFAULT NULL COMMENT '出生日期',
`created` datetime DEFAULT NULL COMMENT '创建时间',
`updated` datetime DEFAULT NULL COMMENT '更新时间',
PRIMARY KEY (`id`),
UNIQUE KEY `username` (`user_name`)
) ENGINE=InnoDB AUTO_INCREMENT=7 DEFAULT CHARSET=utf8;
-- ----------------------------
-- Records of t_user
-- ----------------------------
INSERT INTO `t_user` VALUES ('1', 'zhangsan', '123456', '练涛', '30', '1', '1984-08-08', '2014-09-19 16:56:04', '2014-09-21 11:24:59');
4、在src/main/java下创建包com.liantao.pojo，在pojo下创建实体类User.java
package com.liantao.pojo;
import java.util.Date;
public class User {
//用户id
private Long id;
// 用户名
private String userName;
// 密码
private String password;
// 姓名
private String name;
// 年龄
private Integer age;
// 性别， 1男性， 2女性
private Integer sex;
// 出生日期
private Date birthday;
// 创建时间
private Date created;
// 更新时间
private Date updated;
public User(){
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
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 getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public Integer getSex() {
return sex;
}
public void setSex(Integer sex) {
this.sex = sex;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public Date getCreated() {
return created;
}
public void setCreated(Date created) {
this.created = created;
}
public Date getUpdated() {
return updated;
}
public void setUpdated(Date updated) {
this.updated = updated;
}
@Override
public String toString() {
return "User [id=" + id + ", userName=" + userName + ", password=" + password + ", name=" + name
+ ", age=" + age + ", sex=" + sex + ", birthday=" + birthday + ", created=" + created
+ ", updated=" + updated + "]";
}
}
5、在src/main/resources创建mybatis-config.xml
记得改为你自己的配置
<?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/ssm"/>
<property name="username" value="root"/>
<property name="password" value="admin"/>
</dataSource>
</environment>
</environments>
<mappers>
<!-- 默认为classpath目录-->
<mapper resource="mapper/UserMapper.xml"/>
</mappers>
</configuration>
注意mapers下的mapper的resource地址不要写错
6、创建User实体方法定义，在src/main/resources下创建文件夹mapper，然后创建UserMapper.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根标签 namespace命名空间 唯一 -->
<mapper namespace="UserMapper">
<!-- 查询id标识(唯一) resultType 返回类型 -->
<select id="selectUser" resultType="com.liantao.pojo.User">
select * from t_user where id = #{id}
</select>
</mapper>
7、在main/java下创建com.liantao.mybatis包，再创建MyBatisDemo.java
package com.liantao.mybatis;
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;
import com.liantao.pojo.User;
public class MybatisDemo {
public static void main(String[] args) throws IOException {
//mybatis配置文件 默认路径org/mybatis/example/mybatis-config.xml
String resource = "mybatis-config.xml";
//读取配置文件信息
InputStream is = Resources.getResourceAsStream(resource );
//构件SqlSessionFactory
SqlSessionFactory sf = new SqlSessionFactoryBuilder().build(is);
//获取sqlSession
SqlSession session = sf.openSession();
try {
//参数1 标识要寻找的statement对象 即UserMapper.xml 参数2 标识要传入的参数
User user = (User) session.selectOne("UserMapper.selectUser", 1);
System.out.println(user);
} finally {
//关闭sqlSession
session.close();
}
}
}
运行测试：
每天进步一点点！🏃
