Mybatis之使用注解开发CRUD

上一篇演示了如何使用XML来操作Mybatis实现CRUD，但是大量的XML配置文件的编写是非常烦人的。因此

Mybatis也提供了基于注解的配置方式，下面我们来演示一下使用接口加注解来实现CRUD的的例子。

首先是创建一个接口。

package com.bird.mybatis.bean;

import java.util.List;

import org.apache.ibatis.annotations.Delete;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.annotations.Update;

public interface UserMapper {
	@Insert("insert into users(name, age) values(#{name}, #{age})")
	public int add(Users user);
	
	@Delete("delete from users where id = #{id}")
	public int deleteById(int id);
	
	@Update("update users set name = #{name}, age = #{age} where id = #{id}")
	public int update(Users user);
	
	@Select("select * from users where id = #{id}")
	public Users getUserById(int id);
	
	@Select("select * from users")
	public List<Users> getAllUsers();
}

<mappers>
		<mapper resource="com/bird/mybatis/bean/userMapper.xml" />
		<mapper class="com.bird.mybatis.bean.UserMapper"/>
	</mappers>

@Test
	public void testAdd2() {
		SqlSession openSession = factory.openSession();
		UserMapper mapper = openSession.getMapper(UserMapper.class);
		mapper.add(new Users(-1,"娃娃",99));
		openSession.commit();
		openSession.close();
	}