开发工具:IDEA
开发步骤:
一、建立maven项目
<?xml version="1.0" encoding="UTF-8"?>
<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>
<groupId>com.jd.xia</groupId>
<artifactId>test-ibatis</artifactId>
<packaging>pom</packaging>
<version>1.0-SNAPSHOT</version>
<modules>
<module>test-mybatis</module>
<module>test-ibatis1</module>
</modules>
<dependencies>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.31</version>
</dependency>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.1.1</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>4.3.13.RELEASE</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.apache.ibatis/ibatis-sqlmap -->
<dependency>
<groupId>org.apache.ibatis</groupId>
<artifactId>ibatis-sqlmap</artifactId>
<version>2.3.4.726</version>
</dependency>
</dependencies>
</project>
二、建立mybatis模块
mybatis通过xml配置文件与Mapper接口建立映射关系,在进行数据库操作室,只需声明Mapper接口对象,java虚拟机会在运行过程中利用反射机制根据xml配置文件建立Mapper的实体类。
package com.mongo.mybatis;
import java.util.List;
public interface UserMapper {
List<User> selectById(Integer id);
}
<?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" />
<!-- 配置数据库连接信息 -->
<dataSource type="POOLED">
<property name="driver" value="com.mysql.jdbc.Driver" />
<property name="url" value="jdbc:mysql://localhost:3306/test" />
<property name="username" value="root" />
<property name="password" value="123456" />
</dataSource>
</environment>
</environments>
<mappers>
<mapper resource="userMapper.xml"/>
</mappers>
</configuration>
<?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.mongo.mybatis.UserMapper">
<!--
根据id查询得到一个user对象
-->
<select id="selectById" parameterType="int"
resultType="com.mongo.mybatis.User">
select * from user where id=#{id}
</select>
</mapper>
package com.mongo.mybatis;
public class User {
private Integer id;
private String username;
public User(Integer id, String username) {
this.id = id;
this.username = username;
}
public User() {
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
@Override
public String toString() {
return "User{" +
"id=" + id +
", username='" + username + '\'' +
'}';
}
}
package com.mongo.mybatis;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;
public class Main {
public static void main(String[] args) throws IOException {
//mybatis的配置文件
String resource = "mybatis-config.xml";
//使用类加载器加载mybatis的配置文件(它也加载关联的映射文件)
InputStream is = Main.class.getClassLoader().getResourceAsStream(resource);
//构建sqlSession的工厂
SqlSessionFactory sessionFactory = new SqlSessionFactoryBuilder().build(is);
//使用MyBatis提供的Resources类加载mybatis的配置文件(它也加载关联的映射文件)
//Reader reader = Resources.getResourceAsReader(resource);
//构建sqlSession的工厂
//SqlSessionFactory sessionFactory = new SqlSessionFactoryBuilder().build(reader);
//创建能执行映射文件中sql的sqlSession
SqlSession session = sessionFactory.openSession();
/**
* 映射sql的标识字符串,
* me.gacl.mapping.userMapper是userMapper.xml文件中mapper标签的namespace属性的值,
* getUser是select标签的id属性值,通过select标签的id属性值就可以找到要执行的SQL
*/
//String statement = "com.mongo.mybatis.User";//映射sql的标识字符串
UserMapper userMapper = session.getMapper(UserMapper.class);
//执行查询返回一个唯一user对象的sql
List<User> users = userMapper.selectById(1);
System.out.println(users);
session.close();
}
}
github:https://github.com/xhyflowcloud/ORM.git