所需要用到的其他工具或技术:
项目管理工具 : Maven
测试运行工具 : Junit
数据库 : Derby
Maven Dependencies:
<dependencies>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.2.7</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.9</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.apache.derby</groupId>
<artifactId>derby</artifactId>
<version>10.10.2.0</version>
</dependency>
<dependency>
<groupId>org.apache.derby</groupId>
<artifactId>derbyclient</artifactId>
<version>10.10.2.0</version>
</dependency>
</dependencies>
SQL 建表及数据插入（新建一个USER_TEST_TB_RELATIONSHIP表，然后CopyUSER_TEST_TB的数据，Derby不支持表结构中列名的修改，只能这么做了）:
CREATE TABLE USER_TEST_TB_RELATIONSHIP( USER_ID INT PRIMARY KEY, USER_USERNAME VARCHAR(20) NOT NULL, USER_PASSWORD VARCHAR(20) NOT NULL, USER_NICKNAME VARCHAR(20) NOT NULL ); INSERT INTO USER_TEST_TB_RELATIONSHIP(USER_ID,USER_USERNAME,USER_PASSWORD,USER_NICKNAME) SELECT ID,USERNAME,PASSWORD,NICKNAME FROM USER_TEST_TB;
Mybatis配置文件 src/main/resource源目录下
test-mybatis-configuration.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>
<property name="driver" value="org.apache.derby.jdbc.ClientDriver" />
<property name="url" value="jdbc:derby://localhost:1527/bjpowernode;create=true" />
</properties>
<environments default="development">
<environment id="development">
<transactionManager type="JDBC" />
<dataSource type="POOLED">
<property name="driver" value="${driver}" />
<property name="url" value="${url}" />
</dataSource>
</environment>
</environments>
<mappers>
<mapper resource="com/bjpowernode/practice/UserMapper.xml" />
</mappers>
</configuration>
User.java对象类(src/main/java/com/bjpowernode/practice目录下)
package com.bjpowernode.practice;
public class User
{
private Integer id;
private String username;
private String password;
private String nickname;
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;
}
public String getPassword()
{
return password;
}
public void setPassword(String password)
{
this.password = password;
}
public String getNickname()
{
return nickname;
}
public void setNickname(String nickname)
{
this.nickname = nickname;
}
}
UserMapper.xml Mapper文件（src/main/java/com.bjpowernode.practice目录下）
<?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="com.bjpowernode.practice.UserMapper">
<!-- 对象属性和表字段的对应 -->
<resultMap id="userResultMap" type="com.bjpowernode.practice.User">
<result property="id" column="USER_ID"/>
<result property="username" column="USER_USERNAME"/>
<result property="password" column="USER_PASSWORD"/>
<result property="nickname" column="USER_NICKNAME"/>
</resultMap>
<select id="getUser" resultMap="userResultMap">
select *
from USER_TEST_TB_RELATIONSHIP
</select>
</mapper>
UserMapper.java Mapper类（src/main/java/com.bjpowernode.practice目录下）
package com.bjpowernode.practice;
import java.util.List;
public interface UserMapper
{
public List<User> getUser();
}
测试类TestMyBatis.Java（src/test/java/com.bjpowernode.practice目录下）
package com.bjpowernode.practice;
import java.io.InputStream;
import java.text.MessageFormat;
import java.util.List;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.Before;
import org.junit.Test;
public class TestMyBatis
{
private String source;
private InputStream inputStream;
private SqlSessionFactory sqlSessionFactory;
@Before
public void setUp()
{
/**
* 准备Mybatis运行环境
*/
source = "test-mybatis-configuration.xml";
inputStream = TestMyBatis.class.getClassLoader().getResourceAsStream(source);
sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
}
@Test
public void testGet()
{
try
{
// 获取Session连接
SqlSession session = sqlSessionFactory.openSession();
// 获取Mapper
UserMapper userMapper = session.getMapper(UserMapper.class);
// 显示User信息
System.out.println("Test Get start...");
this.printUsers(userMapper.getUser());
System.out.println("Test Get finished...");
}
catch (Exception e)
{
e.printStackTrace();
}
}
/**
*
* 打印用户信息到控制台
*
* @param users
*/
private void printUsers(final List<User> users)
{
int count = 0;
for (User user : users)
{
System.out.println(MessageFormat.format("==User[{0}]=================", ++count));
System.out.println("User Id: " + user.getId());
System.out.println("User UserName: " + user.getUsername());
System.out.println("User Password: " + user.getPassword());
System.out.println("User nickname: " + user.getNickname());
}
}
}
总结
以上所述是小编给大家介绍的mybatis实现表与对象的关联关系_动力节点Java学院整理，希望对大家有所帮助，如果大家有任何疑问请给我留言，小编会及时回复大家的。在此也非常感谢大家对呐喊教程网站的支持！