DAO介面：

package com.sunxl.dao;

import com.sunxl.pojo.User;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.annotations.SelectKey;
import org.apache.ibatis.annotations.Update;

import java.util.List;

public interface UserDao {

    @Select(
 
"select * from users")
    List<User> findAll();

    @Insert("insert into users (name,age) values(#{name},#{age})")
    @SelectKey(statement = "select last_insert_id()", keyProperty = "id", keyColumn = "id", resultType = int.class ,before = false)
    int saveUser(User user);


    @Update("update users set name = #{name},age = #{age} where id = #{id}")
    
 
int updateUser(User user);
//
//    int deleteUser(Integer id);
//
//    User findById(Integer id);
//
//    List<User> findByName(String name);
//
//    int findTotal();
//
//    int saveInsertUser(User user);

}

測試執行：

import com.sunxl.dao.UserDao;
import com.sunxl.pojo.User;
import org.apache.ibatis.io.Resources;
 
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;

public class MybatisTest {

    public static void main(String[] args) throws IOException {

//        InputStream config = Resources.getResourceAsStream("mybatis-config.xml");
//
//        SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
//        SqlSessionFactory factory = builder.build(config);
//        SqlSession ss = factory.openSession();
//        UserDao userdao = ss.getMapper(UserDao.class);
//
//
//        List<User> users = userdao.findAll();
//
//        for (User user: users){
//            System.out.println(user);
//        }
//
//
//        ss.commit();
//        ss.close();
//        config.close();



        InputStream config = Resources.getResourceAsStream("mybatis-config.xml");

        SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
        SqlSessionFactory factory = builder.build(config);
        SqlSession ss = factory.openSession();
        UserDao userdao = ss.getMapper(UserDao.class);

        User as = new User();
        as.setName("mei_guo");
        as.setAge(1005);
        as.setId(1005);

        int a = userdao.updateUser(as);
        System.out.println(a);
        System.out.println(as.toString());



        ss.commit();
        ss.close();
        config.close();


    }
}