mybatis文件配置及简单应用
- 需求
- 根据用户id(主键)查询用户信息
- 模糊查询
- 添加、删除、更新用户
- 环境
- mybatis
- mybatis
01_基础运行文件
实体类
package org.vector.entity;
public class User {
private int cid;
private String username;
private String password;
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public int getCid() {
return cid;
}
public void setCid(int cid) {
this.cid = cid;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
@Override
public String toString() {
return "User [cid=" + cid + ", username=" + username + ", password="
+ password + "]";
}
}
配置文件
全局配置文件
SqlMapConfig.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>
<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/test4"/>
<property name="username" value="root"/>
<property name="password" value="123"/>
</dataSource>
</environment>
</environments>
<mappers>
<mapper resource="org/vector/entity/userMapper.xml"/>
</mappers>
</configuration>
映射文件
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 namespace="org.vector.entity.UserMapper">
<select id="selectUser" parameterType="int" resultType="org.vector.entity.User">
select * from t_customer where cid = #{cid}
</select>
</mapper>
测试类
// 根据id查询
public class Demo {
@Test
public void test() throws IOException {
String resource = "SqlMapConfig.xml";
InputStream inputStream = Resources.getResourceAsStream(resource);
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
SqlSession session = sqlSessionFactory.openSession();
User user = session.selectOne("org.vector.entity.userMapper.selectUser", 1);
System.out.println(user);
session.close();
}
}
第2个基础运行文件的源程序路径
02_基础运行文件
实体类
package org.vector.entity;
public class User {
private int cid;
private String username;
private String password;
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public int getCid() {
return cid;
}
public void setCid(int cid) {
this.cid = cid;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
@Override
public String toString() {
return "User [cid=" + cid + ", username=" + username + ", password="
+ password + "]";
}
}
配置文件
properties 文件
driver=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/test4
username=root
password=123
全局配置文件
<?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 resource="db.properties"/>
<typeAliases>
<!-- 使用别名:
映射文件中:
namespace:直接使用映射文件名
resultType:如果返回类型为实体类类型,直接写实体类名
测试类中:
对sql进行操作时,直接使用映射文件名.映射文件中的id名
-->
<package name="org.vector.entity"/>
</typeAliases>
<environments default="development">
<environment id="development">
<transactionManager type="JDBC"/>
<dataSource type="POOLED">
<property name="driver" value="${driver}"/>
<property name="url" value="${url}"/>
<property name="username" value="${username}"/>
<property name="password" value="${password}"/>
</dataSource>
</environment>
</environments>
<mappers>
<mapper resource="org/vector/entity/userMapper.xml"/>
</mappers>
</configuration>
映射文件
<?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="userMapper">
<select id="selectUser" parameterType="int" resultType="User">
select * from t_customer where cid = #{cid}
</select>
</mapper>
测试类
// 根据id查询
public class Demo {
@Test
public void test() throws IOException {
String resource = "SqlMapConfig.xml";
InputStream inputStream = Resources.getResourceAsStream(resource);
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
SqlSession session = sqlSessionFactory.openSession();
User user = session.selectOne("userMapper.selectUser", 1);
System.out.println(user);
session.close();
}
}