java 数据库 ORM思想和DAO模式

\C11-6\src\com\data\entity\User.java

package com.data.entity;

import java.io.Serializable;

public class User implements Serializable {
    public Integer userId;
    public String userName;
    public String password;

    public User() {
    }

    public User(Integer userId, String userName, String password) {
        this.userId = userId;
        this.userName = userName;
        this.password = password;
    }

    public Integer getUserId() {
        return userId;
    }

    public void setUserId(Integer userId) {
        this.userId = userId;
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    @Override
    public String toString() {
        return "User{" +
                "userId=" + userId +
                ", userName='" + userName + '\'' +
                ", password='" + password + '\'' +
                '}';
    }


}

\C11-6\src\com\user\dao\UserDao.java

package com.user.dao;

import com.data.entity.User;

import java.util.List;

public interface UserDao {
    /**
     * 添加用户
     * @param user 用户类
     * @return 影响行
     */
    public int insertUser(User user);

    /**
     * 删除数据
     * @param id 删除ID
     * @return 影响行
     */
    public int deleteUser(int id);

    /**
     * 修改数据
     * @param user 用户类
     * @return 影响行
     */
    public int updateUserId(User user);

    /**
     * 查询用户
     * @param id ID
     * @return 用户数组
     */
    public List<User> selectUserId(int id);

    /**
     * 查询所有
     * @return
     */
    public List<User> selectUser();
}

\C11-6\src\com\user\dao\impl\Userimpl.java

package com.user.dao.impl;


import com.data.entity.Mysql_Template_conn;
import com.data.entity.User;
import com.user.dao.UserDao;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;

import java.util.List;

public class Userimpl implements UserDao {

    public Mysql_Template_conn conn;
    public Userimpl() {
        this.conn=new Mysql_Template_conn(
                "localhost","root","1234567890","data","3306","UTF-8");
    }

    @Override
    public int insertUser(User user) {
        if(this.conn.getConnection()) {  // 建立连接
            String  insertDataxx = "INSERT into user(user_name,password) values(?,?)";
            return this.conn.update(insertDataxx,user.getUserName(),user.getPassword());    //动态参数
        }
        return 0;
    }

    @Override
    public int deleteUser(int id) {
        if(this.conn.getConnection()) {  // 建立连接
            String  insertDataxx = "DELETE FROM user WHERE user_id=?";
            return this.conn.update(insertDataxx,id);    //动态参数
        }
        return 0;
    }

    @Override
    public int updateUserId(User user) {
        if(this.conn.getConnection()) {  // 建立连接
            String  insertDataxx = "update user set user_name=?,password=?  where user_id=?";
            return this.conn.update(insertDataxx,user.getUserName(),user.getPassword(),user.getUserId());    //动态参数
        }
        return 0;
    }

    @Override
    public List<User> selectUserId(int id) {
        List<User> resultList =null;
        if(this.conn.getConnection()) {  // 建立连接
            JdbcTemplate jdbcTemplate = new JdbcTemplate(this.conn.conn);
            return jdbcTemplate.query("SELECT * FROM user where user_id=?", new BeanPropertyRowMapper<>(User.class),id);
        }
        return resultList;
    }

    @Override
    public List<User> selectUser() {
        List<User> resultList =null;
        if(this.conn.getConnection()) {  // 建立连接
            JdbcTemplate jdbcTemplate = new JdbcTemplate(this.conn.conn);
            return jdbcTemplate.query("SELECT * FROM user", new BeanPropertyRowMapper<>(User.class));
        }
        return resultList;
    }
}

\C11-6\src\text11.java

import com.data.entity.User;
import com.user.dao.UserDao;
import com.user.dao.impl.Userimpl;

public class text11 {
    public static void main(String[] args) {
        UserDao add=new Userimpl();
        System.out.println(add.insertUser(new User(null,"abc","123465")));

        System.out.println(add.deleteUser(2));

        add.updateUserId(new User(1,"abc111","111111"));

        add.selectUserId(1).forEach(ss->{
            System.out.println(ss);
        });

        add.selectUser().forEach(ff->{
            System.out.println(ff);
        });

    }
}