参考
- 请注意后面文章中的注释
- MyBatis官方入门：http://mybatis.github.io/mybatis-3/zh/getting-started.html
- 源代码下载：（正在审核中）
代码结构
1. config：配置文件目录 2. pojo：Bean类包 3. controller：数据接口 4. sql：数据库源文件
数据库创建
CREATE DATABASE IF NOT EXISTS `mybatis`; USE `mybatis`; DROP TABLE IF EXISTS `users`; CREATE TABLE `users` ( `id` int(11) NOT NULL AUTO_INCREMENT, `name` varchar(45) DEFAULT NULL, `age` int(11) DEFAULT NULL, `phone` varchar(45) DEFAULT NULL, PRIMARY KEY (`id`) ) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8; LOCK TABLES `users` WRITE; INSERT INTO `users` VALUES (1,‘jimmy.song‘,22,‘13810001234‘),(2,‘sunspot‘,24,‘13812341234‘); UNLOCK TABLES;
创建链接数据库的配置
位置：cc/fozone/demo/mybatis/config/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> <!-- 配置数据库链接 --> <environments default="development"> <environment id="development"> <transactionManager type="JDBC"/> <dataSource type="POOLED"> <!-- 数据库链接驱动 --> <property name="driver" value="org.gjt.mm.mysql.Driver"/> <!-- 数据库链接 --> <property name="url" value="jdbc:mysql://localhost:3306/mybatis?charset=utf8"/> <!-- 数据库帐号密码 --> <property name="username" value="root"/> <property name="password" value="root"/> </dataSource> </environment> </environments> <!-- 与数据库映射的配置文件列表 --> <mappers> <mapper resource="cc/fozone/demo/mybatis/config/mapper/User.mapper.xml"/> </mappers> </configuration>
创建User类
位置：cc/fozone/demo/mybatis/pojo/User.java
package cc.fozone.demo.mybatis.pojo;
public class User {
private int id;
private String name;
private int age;
private String phone;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public String getPhone() {
return phone;
}
public void setPhone(String phone) {
this.phone = phone;
}
public String toString(){
return "{id:"+id+",name:"+name+",age:"+age+",phone:"+phone+"}";
}
}
创建User的数据接口
位置：cc/fozone/demo/mybatis/controller/IUserController.java
package cc.fozone.demo.mybatis.controller;
import java.util.List;
import cc.fozone.demo.mybatis.pojo.User;
public interface IUserController {
// 查询所有的用户
public List<User> getAllUsers();
// 根据电话查询用户
public User getUser(String phone);
}
创建User表对应的映射配置
位置：cc/fozone/demo/mybatis/config/mapper/User.mapper.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">
<!--
namespace：与Controller接口匹配
-->
<mapper namespace="cc.fozone.demo.mybatis.controller.IUserController">
<!--
User表映射
type：类地址
id：实例化ID
-->
<resultMap type="cc.fozone.demo.mybatis.pojo.User" id="userResultMap">
<id property="id" column="id" />
<result property="name" column="name" />
<result property="age" column="age"/>
<result property="phone" column="phone"/>
</resultMap>
<!--
select 查询语句
id：唯一标示符，与Controller的接口方法一致
resultMap： 查询的数据实例化注入的对象标示引用
-->
<select id="getAllUsers" resultMap="userResultMap">
<![CDATA[
select id,name,age,phone from users
]]>
</select>
<!--
#{phone}：参数，与Controller中的getUser方法中的参数一致
resultType：查询的数据库实例化注入的类型，与resultMap不能同时使用，但建议使用resultMap
-->
<select id="getUser" resultType="cc.fozone.demo.mybatis.pojo.User">
<![CDATA[
select id,name,age,phone from users where phone = #{phone}
]]>
</select>
</mapper>
模拟服务调用
位置：cc/fozone/demo/mybatis/App.java
package cc.fozone.demo.mybatis;
import java.io.IOException;
import java.io.InputStream;
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 cc.fozone.demo.mybatis.controller.IUserController;
import cc.fozone.demo.mybatis.pojo.User;
/**
* Hello world!
*
*/
public class App {
// 数据库链接配置
private static final String CONFIG = "cc/fozone/demo/mybatis/config/mybatis.config.xml";
// SQL会话工厂
private SqlSessionFactory factory;
public App() {
// 初始化
this.init();
}
// 初始化SQL会话工厂
private void init() {
InputStream input;
try {
input = Resources.getResourceAsStream(CONFIG);
this.factory = new SqlSessionFactoryBuilder().build(input);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
// 查询所有用户列表
public List<User> getUsers() {
// 打开会话
SqlSession session = this.factory.openSession();
// 根据映射实例化控制器对象，这里的IUserController.class与Mapper配置中的namespace一致
IUserController controller = session.getMapper(IUserController.class);
// 获得所有用户
List<User> list = controller.getAllUsers();
// 关闭会话
session.close();
return list;
}
// 根据电话号查询用户
public User getUser(String phone) {
User user = null;
// 会话
SqlSession session = this.factory.openSession();
IUserController controller = session.getMapper(IUserController.class);
// 查询用户，这里传入的参数会被替换在Mapper中的#{phone}占位符
user = controller.getUser(phone);
session.close();
return user;
}
}
创建测试用例
位置：cc/fozone/demo/mybatis/AppTest.java
package cc.fozone.demo.mybatis;
import java.util.List;
import org.junit.Before;
import org.junit.Test;
import static org.junit.Assert.*;
import cc.fozone.demo.mybatis.pojo.User;
public class AppTest {
private App app;
@Before
public void setUp() throws Exception {
app = new App();
assertNotNull(app);
}
@Test
public void testList() {
List<User> list = app.getUsers();
assertEquals(2,list.size());
}
@Test
public void testUser(){
User user = app.getUser("13810001234");
assertNotNull(user);
assertEquals("jimmy.song", user.getName());
}
}
结果
AppTest.java文件鼠标右键 -> Run -> JUnit Test
时间： 2024-11-04 19:40:06