Mybaits基本的CURD操作

1 首先在Mapper.xml配置

<!-- parameterType：参数类型，可以省略，
获取自增主键的值：
mysql支持自增主键，自增主键值的获取，mybatis也是利用statement.getGenreatedKeys()；
useGeneratedKeys="true"；使用自增主键获取主键值策略
keyProperty；指定对应的主键属性，也就是mybatis获取到主键值以后，将这个值封装给javaBean的哪个属性
-->
<insert id="addEmp" parameterType="com.atguigu.mybatis.bean.Employee"
useGeneratedKeys="true" keyProperty="id" databaseId="mysql">
insert into tbl_employee(last_name,email,gender)
values(#{lastName},#{email},#{gender})
</insert>

<select id="getEmpById" resultType="com.atguigu.mybatis.bean.Employee"
databaseId="mysql">
select * from tbl_employee where id = #{id}
</select>

<update id="updateEmp">
update tbl_employee
set last_name=#{lastName},email=#{email},gender=#{gender}
where id=#{id}
</update>


<delete id="deleteEmpById">
delete from tbl_employee where id=#{id}
</delete>

2在映射java类中添加对应方法

public Employee getEmpById(Integer id);

public Long addEmp(Employee employee);

public boolean updateEmp(Employee employee);

public boolean deleteEmpById(Integer id);

3在junit测试方法执行

public SqlSessionFactory getSqlSessionFactory() throws IOException {
String resource = "mybatis-config.xml";
InputStream inputStream = Resources.getResourceAsStream(resource);
return new SqlSessionFactoryBuilder().build(inputStream);
}

@Test
public void test03() throws IOException{

SqlSessionFactory sqlSessionFactory = getSqlSessionFactory();
//1、获取到的SqlSession不会自动提交数据
SqlSession openSession = sqlSessionFactory.openSession();

try{
EmployeeMapper mapper = openSession.getMapper(EmployeeMapper.class);
//测试添加
Employee employee = new Employee(null, "jerry4",null, "1");
Employee employee2 = new Employee(null, "jerry2",null, "1");
mapper.addEmp(employee2);
Long a=mapper.addEmp(employee);
System.out.println(employee.getId());
System.out.println(a);
// //测试修改
// Employee employee1 = new Employee(1, "Tom", "jerry@atguigu.com", "0");
// boolean updateEmp = mapper.updateEmp(employee1);
// System.out.println(updateEmp);
// //测试删除
// boolean updateEmp1= mapper.deleteEmpById(2);
// if(updateEmp1==true){
// System.out.println("删除成功");
// }
//2、手动提交数据
openSession.commit();
}finally{
openSession.close();
}

}