sql文件

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不能忘了

1.核心配置文件

1.1maven核心

1.2mybatis核心

2.properties文件

3. 实体

package demo01.pojo;
import lombok.Getter;
import lombok.Setter;
import lombok.ToString;

import java.util.Calendar;
import java.util.Date;
@Getter
@Setter

@ToString(of = {"userId", "userCode", "userName", "birthday", "roleId", "roleName", "creationDate"})
public class User {
  private Integer userId;
  private String userCode;
  private String userName;
  private String userPassword;
  private Integer gender;
  private Date birthday;
  private String phone;
  private String address;
  private Integer roleId;
  private String roleName;
  private Integer createdBy;
  private java.sql.Timestamp creationDate;
  private Integer modifyBy;
  private java.sql.Timestamp modifyDate;
  private String idPicPath;
  private String workPicPath;
  private Integer age;
  public Integer getAge() {
    Calendar calendar1 = Calendar.getInstance();
    Calendar calendar2 = Calendar.getInstance();
    calendar1.setTime(new Date());
    calendar2.setTime(birthday);
    age = calendar1.get(Calendar.YEAR) - calendar2.get(Calendar.YEAR);
    return age;
  }
}

4.DAO,接口 

package demo01.dao;

import demo01.pojo.User;

import java.util.List;

/**
 * @Title
 * @Author Eastlin
 * @Description:
 */
public interface UserDao {
    //查询用户记录数
    int count();
    //查询所有的用户
    List<User> getUsers();
}

5.Mapper 

<?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">
<mapper namespace="demo01.dao.UserDao">
  <select id="count" resultType="int">
    select count(*)
    from smbms_user
  </select>
<!--  smbms_user报红，是右边database没有配置，alt+/不会自动补全是没有设置方言-->
  <select id="getUsers" resultType="demo01.pojo.User">
    select u.*,rolename from smbms_user u inner join smbms_role r
    on u.roleId=r.roleId
  </select>
</mapper>

 test文件，测试接口

package demo01.dao;

import org.apache.ibatis.io.Resources;//选择这个
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.*;
//import org.junit.Test;
//import static org.junit.Assert.*;

import java.io.IOException;
import java.io.InputStream;


public class UserDaoTest {

    @Test
    public void count() throws IOException {
        //文件名
        String mybatisConfig="mybatis-config.xml";
        //throws IOException
        //ibatis下Resources读取，输入String的文件名参数
        //可选stream方式读取
        InputStream in= Resources.getResourceAsStream(mybatisConfig);
        //可类比为数据库连接池中的一个连接
        SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(in);
        SqlSession sqlSession=null;

        try {
            //打开连接
            sqlSession=sqlSessionFactory.openSession();
            //方式1,执行查询
            int count=sqlSession.selectOne("demo01.dao.UserDao.count");
            System.out.println(count);
        } finally {
            if(sqlSession!=null){
                sqlSession.close();
            }
        }

    }
}

输出

12