mybatis实现增删改查 Mybatis开发环境搭建实现数据的增删改查功能

<?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>
<!-- 
拿到数据库信息，这是db.properties的内容
driver=com.MySQL.jdbc.Driver
url=jdbc:mysql://localhost:3306/usertest
username=root
password=root
--!>
<properties resource="db.properties">
</properties>
<!-- 别名优化--!>
<typeAliases>
<!-- <package name="com.leige.entity" /> -->
<typeAlias type="com.leige.entity.User" alias="user"/>
</typeAliases>
<!--设置框架工作模式development开发者模式 ，work是工作模式 -->
<environments default="development">
<environment id="development">
<transactionManager type="jdbc"></transactionManager>
<!-- 配置数据源 -->
<dataSource type="POOLED">
<!-- 注册驱动 -->
<property name="driver" value="${driver}"/>
<!-- 连接数据库 -->
<property name="url" value="${url}"/>
<!-- 密码帐号登录 -->
<property name="username" value="${username}"/>
<property name="password" value="${password}"/>
</dataSource>
</environment>
</environments>
<!-- 使用xml，mapper resource需要设置--!>
<!-- <mappers>
<mapper resource="com/leige/entity/UserMappen.xml"></mapper>
</mappers> -->
<!--使用注解，mapper配置class，查询方法写在接口中--!>
<mappers>
<mapper class="com.leige.impl.UserImpl"/>
</mappers>

<?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">
<!-- 建立表与类的映射关系有两种：一个是xml(倾向)，另一个是注解 -->
<mapper namespace="com.leige.entity.UserMappen">
<!-- 查询全部 -->
<select id="selectAll" resultType="user">
select * from user
</select>
<!-- 增加用户 -->
<update id="insertUser" parameterType="user">
insert into user values (null,#{name},#{password},#{age})
</update>
</mapper>
使用注解则用接口
public interface UserImpl {
//更新用户，更新用@update，查询用@select，插入用@insert，删除使用@delete这些注解
@Update("update user set name=#{name} where id=#{id}")
public void updateUser(User user);
}
demo测试代码
public class Demo {
static InputStream in = null;
static SqlSessionFactory ssf = null;
static{
in = Demo.class.getClassLoader().getResourceAsStream("config.xml");
ssf = new SqlSessionFactoryBuilder().build(in);
}
public static void main(String[] args) {
//selectAll();
//insertUser();
updateUser();
}
//查询全部
public static void selectAll(){
SqlSession session = ssf.openSession();
List<User> list = session.selectList("com.leige.entity.UserMappen.selectAll");
System.out.println(list);
session.close();
}
//增加用户
public static void insertUser(){
SqlSession session = ssf.openSession();
User user = new User();
user.setName("小霸王");
user.setPassword("aaaaa");
user.setAge(25);
int num = session.insert("com.leige.entity.UserMappen.insertUser",user);
session.commit();
System.out.println(num);
session.close();
}
//修改用户信息
public static void updateUser(){
SqlSession session = ssf.openSession();
UserImpl userImpl = session.getMapper(UserImpl.class);
User user = new User();
user.setName("我是大头鬼");
user.setPassword("aaaaa");
user.setAge(25);
user.setId(79);
userImpl.updateUser(user);
session.commit();
session.close();
}
}
</configuration>