一、基于XML实现
1.定义SQL映射XML文件
studentMapper.xml：
<mapper namespace="com.mapping.studentMapper">
<!-- 在select标签中编写查询的SQL语句， 设置select标签的id属性为getStudent，id属性值必须是唯一的，不能够重复
使用parameterType属性指明查询时使用的参数类型，resultType属性指明查询返回的结果集类型
resultType="com.domain.User"就表示将查询结果封装成一个Student类的对象返回
Student类就是student表所对应的实体类
-->
<!-- 根据id查询得到一个student对象 -->
<select id="getStudent" parameterType="int"
resultType="com.domain.Student">
select * from ksl_student where sid=#{sid}
</select>
<!-- 创建Student -->
<insert id="addStudent" parameterType="com.domain.Student">
insert into ksl_student(sname, sage, ssex) values (#{sname}, #{sage}, #{ssex})
</insert>
<!-- 删除Student -->
<delete id="deleteStudent" parameterType="int">
delete from ksl_student where sid = #{sid}
</delete>
<!-- 修改Student -->
<update id="updateStudent" parameterType="com.domain.Student">
update ksl_student set sname = #{sname}, sage = #{sage}, ssex = #{ssex} where sid = #{sid}
</update>
<!-- 查看全部Student -->
<select id="getAllStudents" resultType="com.domain.Student">
select * from ksl_student
</select>
</mapper>
2.测试代码举例：
SqlSession sqlSession = MyBatisUtil.getSqlSession(false);
String statement = "com.mapping.studentMapper.addStudent";
Student s = new Student();
s.setSage(34);
s.setSname("liqingzhao");
s.setSsex("girl");
// 执行插入操作（返回值代表受影响的行数）
int res = sqlSession.insert(statement, s);
// 手动提交事务
sqlSession.commit();
sqlSession.close();
System.out.println(res);
二、基于注解实现
1.定义SQL映射的接口
（我们不需要针对接口去编写具体的实现类代码，具体的实现类由MyBatis动态构建出来，我们可以直接拿来使用）
public interface StudentMapperI {
@Insert("insert into ksl_student(sname, sage, ssex) values (#{sname}, #{sage}, #{ssex})")
public int add(Student student);
@Delete("delete from ksl_student where sid = #{sid}")
public int deleteById(int sid);
@Update("update ksl_student set sname = #{sname}, sage = #{sage}, ssex = #{ssex} where sid = #{sid}")
public int update(Student student);
@Select("select * from ksl_student where sid=#{sid}")
public Student getBySId(int sid);
@Select("select * from ksl_student")
public List<Student> getAll();
}
2.在conf.xml中注册这个接口
<mapper class="com.mapping.StudentMapperI"/>
3.测试代码举例：
@Test
public void testAdd() {
SqlSession sqlSession = MyBatisUtil.getSqlSession(true);
StudentMapperI mapper = sqlSession.getMapper(StudentMapperI.class);
Student s = new Student();
s.setSage(34);
s.setSname("liqingzhao");
s.setSsex("girl");
int res = mapper.add(s);
sqlSession.close();
System.out.println(res);
}
三、工具类
public class MyBatisUtil {
// 获取SqlSessionFactory
public static SqlSessionFactory getSqlSessionFactory() {
String resource = "conf.xml";
InputStream is = MyBatisUtil.class.getClassLoader().getResourceAsStream(resource);
SqlSessionFactory sessionFactory = new SqlSessionFactoryBuilder().build(is);
return sessionFactory;
}
// 获取SqlSession
public static SqlSession getSqlSession() {
return getSqlSessionFactory().openSession();
}
/*
* 获取SqlSession
* @param isAutoCommit
* true 表示创建的SqlSession对象在执行完SQL之后会自动提交事务
* false 表示创建的SqlSession对象在执行完SQL之后不会自动提交事务，这时就需要我们手动调用sqlSession.commit()提交事务
*/
public static SqlSession getSqlSession(boolean isAutoCommit) {
return getSqlSessionFactory().openSession(isAutoCommit);
}
}
原文地址：https://www.cnblogs.com/yuanfei1110111/p/10349471.html