mybatis简单实例
1、什么是持久层?
1、什么是持久化?
3、为什么需要mybatis?
4、什么是mybatis?
5、mybatis的优势
6、实例:
1、mybatis所需jar包:
2、新建数据库mybatis与tb_user表
3、创建user类:
public class User {
private int id;
private String name;
private String sex;
private int age;
public User() {
super();
}
public User( String name, String sex, int age) {
super();
this.name = name;
this.sex = sex;
this.age = age;
}
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 String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
}
4、MyBatis 映射文件 UserMapper.xml配置:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org/DTD Mapper 3.0"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.my.mapper.UserMapper">
//添加user
<insert id="save" parameterType="com.my.vo.User"
useGeneratedKeys="true" keyProperty="id">
insert into tb_user(name,sex,age) values(#{name},#{sex},#{age})
</insert>
//删除user
<insert id="del" parameterType="com.my.vo.User"
useGeneratedKeys="true" keyProperty="id">
delete from tb_user where id=#{id}
</insert>
</mapper>
5、myBatis配置信息 mybatis.cfg.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>
<settings>
<setting name="logImpl" value="LOG4J" />
</settings>
<!-- 配置mybatis运行环境 -->
<environments default="mysql">
<environment id="mysql">
<!-- type="JDBC" 代表使用JDBC的提交和回滚来管理事务 -->
<transactionManager type="JDBC" />
<!-- POOLED 表示支持JDBC数据源连接池 -->
<!-- UNPOOLED 表示不支持数据源连接池 -->
<!-- JNDI 表示支持外部数据源连接池 -->
<dataSource type="POOLED">
<property name="driver" value="com.mysql.jdbc.Driver" />
<property name="url" value="jdbc:mysql://localhost:3306/mybatis" />
<property name="username" value="root" />
<property name="password" value="123" />
</dataSource>
</environment>
</environments>
<mappers>
<!-- 告知映射文件方式1,一个一个的配置-->
<mapper resource="com/my/mapper/UserMapper.xml"/>
</mappers>
</configuration>
5、测试类:
public class MybatisTest {
public static void main(String[] args) throws IOException {
// TODO Auto-generated method stub
InputStream inputStream=Resources.getResourceAsStream("mybatis.cfg.xml");
SqlSessionFactory sqlSessionFactory=
new SqlSessionFactoryBuilder().build(inputStream);
SqlSession session=sqlSessionFactory.openSession();
User user=new User("admin","男",26);
session.insert("com.my.mapper.UserMapper.save", user);
session.commit();
session.close();
}
}