mybaits四:增删改查的实现

定义接口类: 

package com.atChina.dao;

import com.atChina.bean.Employee;

public interface EmployeeMapper {
	public Employee getEmployeeById(Integer depno);
	
	public void addEmploy(Employee employee);
	
	public Integer updateEmp(Employee employee);
	
	public Integer deleteEmpById(Integer id);
}

sql映射文件,增删改查的实现

<?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">
<!-- namespace不能随便自定义了，应该是接口类的全限定名 -->
<mapper namespace="com.atChina.dao.EmployeeMapper">
	<!-- id:唯一标识 ,应该是接口类中的抽象方法名
	resultType: 返回值类型
	#{deptno}:参数 -->
	<select
		id="getEmployeeById"  
		resultType="emp" >
		select * from DEPTTEST where deptno = #{deptno}
	</select>
	
	<!-- parameterType可以省略不写 -->
	<insert id="addEmploy" parameterType="com.atChina.bean.Employee">
		insert into DEPTTEST(deptno, dname, loc) values(#{deptno}, #{dname}, #{loc})
	</insert>
	
	<update id="updateEmp">
		update DEPTTEST a set dname=#{dname}, loc=#{loc}
		where  deptno = #{deptno}
	</update>
	
	<delete id="deleteEmpById">
		delete from DEPTTEST a where deptno = #{deptno}
	</delete>
</mapper>

 测试:

/*
	 * 测试增删改
	 * 1. mybatis允许增删改直接定义以下数据类型返回值
	 *     Integer, Long, Boolean,或者对一个的基本类型  
	 */
	@Test
	public void test03() throws IOException{
		SqlSessionFactory sqlSessionFactory = getSqlSessionFactory();
		// 不会自动提交
		SqlSession openSession = sqlSessionFactory.openSession();
		
		try{
			Employee e = new Employee();
			e.setDeptno(50);
			e.setDname("hehe");
			e.setLoc("earth");
			
			EmployeeMapper em = openSession.getMapper(EmployeeMapper.class);
			//em.addEmploy(e);  增加一条数据
			//em.updateEmp(e);  更新数据
			Integer delete = em.deleteEmpById(50);  // 删除数据
			System.out.println(delete);
			
			// 提交数据
			openSession.commit();
		}finally{
			openSession.close();
		}
	}