本系统是涉及JDBC的一些基本 *** 作,比如增删改,查询等一些 *** 作,首先建立一个java模块(本人再idea中建立),然后为了实现连接数据库 *** 作,我们要去导入mysql中的jar包。
1,导入jar包,这个要去网上下载与你电脑安装的mysql版本一样的jar包,然后进行复制粘贴进入自己所建立的lib文件夹下面
2,复制粘贴完后还需要进行导入
然后点击Library进入add后点击确认就ok啦。
导入完毕后就可以进行编写代码了,
大概代码包如下图所示,你新建这个模块后有可能刚刚添加的jar包依赖没有进入这个模块下面,这个需要自己去手动去添加一下。
接下来各包下面所编写的代码如下:
controller层:下面新建一个Menu类
package com.wwj.fruit.controller;
import com.wwj.fruit.dao.FruitDAO;
import com.wwj.fruit.dao.impl.FruitDAOImpl;
import com.wwj.fruit.pojo.Fruit;
import java.sql.SQLOutput;
import java.util.List;
import java.util.Scanner;
public class Menu {
FruitDAO fruitDAO=new FruitDAOImpl();
//显示主菜单
Scanner input=new Scanner(System.in);
public int showMainMenu(){
System.out.println("=======================欢迎使用水果库存系统======================");
System.out.println("1.查看水果库存列表");
System.out.println("2.添加水果库存信息");
System.out.println("3.查看特定水果库存信息");
System.out.println("4.水果下架");
System.out.println("5.退出");
System.out.println("=============================================================");
System.out.print("请选择: ");
int slt =input.nextInt();
return slt;
}
//查看
public void showFruitList(){
ListfruitList =fruitDAO.getFruitList();
System.out.println("--------------------------------------------------");
System.out.println("编号\t\t名称\t\t单价\t\t库存\t\t备注");
if (fruitList==null || fruitList.size()<=0){
System.out.println("对不起,库存为空");
}else {
for (int i=0;i
dao层:
dao层下面建立一个FruitDAO接口以及FruitDAOImpl实现类
1.impl实现类代码
package com.wwj.fruit.dao.impl;
import com.wwj.fruit.dao.FruitDAO;
import com.wwj.fruit.pojo.Fruit;
import java.sql.*;
import java.util.ArrayList;
import java.util.List;
public class FruitDAOImpl implements FruitDAO {
ResultSet rs;
Connection conn;
PreparedStatement psmt;
final String DRIVER="com.mysql.cj.jdbc.Driver";
final String URL="jdbc:mysql://localhost:3306/fruitdb?useUnicode=true&characterEncoding=utf-8&userSSL=false&serverTimezone=GMT%2B8";
final String USER="root";
final String PWD="root123456";
@Override
public List getFruitList() {
ListfruitList =new ArrayList<>();
try {
//加载驱动
Class.forName(DRIVER);
//通过驱动管理员获取连接对象
conn = DriverManager.getConnection(URL, USER, PWD);
//编写sql语句
String sql ="select * from t_fruit";
//创建1预处理命令对象
psmt =conn.prepareStatement(sql);
//执行查询
rs =psmt.executeQuery();
//解析rs
while (rs.next()){
int fid= rs.getInt(1);
String fname =rs.getString(2);
int price =rs.getInt(3);
int fcount =rs.getInt(4);
String remark =rs.getString(5);
Fruit fruit=new Fruit(fid,fname,price,fcount,remark);
fruitList.add(fruit);
}
} catch (ClassNotFoundException | SQLException e) {
e.printStackTrace();
}finally {
try {
if (rs!=null){
rs.close();
}
if (psmt!=null){
psmt.close();
}
if (conn!=null&&!conn.isClosed()){
conn.close();
}
} catch (Exception e) {
e.printStackTrace();
}
}
return fruitList;
}
@Override
public boolean addFruit(Fruit fruit) {
try {
Class.forName(DRIVER);
conn= DriverManager.getConnection(URL,USER,PWD);
String sql ="insert into t_fruit values(0,?,?,?,?)";
psmt=conn.prepareStatement(sql);
psmt.setString(1,fruit.getFname());
psmt.setInt(2,fruit.getPrice());
psmt.setInt(3,fruit.getFcount());
psmt.setString(4,fruit.getRemark());
return psmt.executeUpdate() >0;
} catch (ClassNotFoundException | SQLException e) {
e.printStackTrace();
}finally {
try {
if (psmt!=null){
psmt.close();
}
if (conn!=null&&!conn.isClosed()){
conn.close();
}
} catch (Exception e) {
e.printStackTrace();
}
}
return false;
}
@Override
public boolean updateFruit(Fruit fruit) {
try {
Class.forName(DRIVER);
conn=DriverManager.getConnection(URL,USER,PWD);
String sql ="update t_fruit set fcount =? where fid =?";
psmt=conn.prepareStatement(sql);
psmt.setInt(1,fruit.getFcount());
psmt.setInt(2,fruit.getFid());
return psmt.executeUpdate() >0;
} catch (ClassNotFoundException | SQLException e) {
e.printStackTrace();
}finally {
try {
if (psmt!=null){
psmt.close();
}
if (conn!=null&&!conn.isClosed()){
conn.close();
}
} catch (Exception e) {
e.printStackTrace();
}
}
return false;
}
@Override
public Fruit getFruitByFname(String fname) {
try {
Class.forName(DRIVER);
conn=DriverManager.getConnection(URL,USER,PWD);
String sql ="select * from t_fruit where fname like ?";
psmt=conn.prepareStatement(sql);
psmt.setString(1,fname);
rs =psmt.executeQuery();
if (rs.next()){
int fid =rs.getInt(1);
int price =rs.getInt(3);
int fcount =rs.getInt(4);
String remark =rs.getString(5);
return new Fruit(fid,fname,price,fcount,remark);
}
} catch (ClassNotFoundException | SQLException e) {
e.printStackTrace();
}finally {
try {
if (rs!=null){
rs.close();
}
if (psmt!=null){
psmt.close();
}
if (conn!=null&&!conn.isClosed()){
conn.close();
}
} catch (Exception e) {
e.printStackTrace();
}
}
return null;
}
@Override
public boolean delFruit(String fname) {
try {
Class.forName(DRIVER);
conn=DriverManager.getConnection(URL,USER,PWD);
String sql="delete from t_fruit where fname like ?";
psmt=conn.prepareStatement(sql);
psmt.setString(1,fname);
return psmt.executeUpdate()>0;
} catch (ClassNotFoundException | SQLException e) {
e.printStackTrace();
}finally {
try {
if (rs!=null){
rs.close();
}
if (psmt!=null){
psmt.close();
}
if (conn!=null&&!conn.isClosed()){
conn.close();
}
} catch (Exception e) {
e.printStackTrace();
}
}
return false;
}
}
2.接口代码
package com.wwj.fruit.dao;
import com.wwj.fruit.pojo.Fruit;
import java.util.List;
public interface FruitDAO {
//查询库存列表
ListgetFruitList();
//新增库存
boolean addFruit(Fruit fruit);
//修改库存
boolean updateFruit(Fruit fruit);
//根据名称查询待定库存
Fruit getFruitByFname(String fname);
//删除待定库存记录
boolean delFruit(String fname);
}
pojo层:
pojo层下面新建一个Fruit类
package com.wwj.fruit.pojo;
public class Fruit {
private Integer fid;
private String fname;
private Integer price;
private Integer fcount;
private String remark;
public Fruit(Integer fid, String fname, Integer price, Integer fcount, String remark) {
this.fid = fid;
this.fname = fname;
this.price = price;
this.fcount = fcount;
this.remark = remark;
}
public Integer getFid() {
return fid;
}
public void setFid(Integer fid) {
this.fid = fid;
}
public String getFname() {
return fname;
}
public void setFname(String fname) {
this.fname = fname;
}
public Integer getPrice() {
return price;
}
public void setPrice(Integer price) {
this.price = price;
}
public Integer getFcount() {
return fcount;
}
public void setFcount(Integer fcount) {
this.fcount = fcount;
}
public String getRemark() {
return remark;
}
public void setRemark(String remark) {
this.remark = remark;
}
@Override
public String toString() {
return fid +"\t\t" + fname + "\t\t" + price +"\t\t"+ fcount +"\t\t" + remark + "\t\t" ;
}
}
view层: view层下面新建一个Client类
package com.wwj.fruit.view;
import com.wwj.fruit.controller.Menu;
public class Client {
public static void main(String[] args) {
Menu m = new Menu();
boolean flag=true;
while (flag)
{
//显示主菜单
int slt = m.showMainMenu();
switch (slt)
{
case 1:
m.showFruitList();
break;
case 2:
m.addFruit();
break;
case 3:
m.showFruitInfo();
break;
case 4:
m.delFruit();
break;
case 5:
flag=m.exit();
break;
default:
System.out.println("你这个老六!!!!");
break;
}
}
System.out.println("谢谢使用!再见!");
}
}
总结: 以上就是水果商城的全部代码快截图,里面代码中设计的数据库账号和密码要换成自己的,本人只是一个小白,第一次编写这个,所以写的不好请大家谅解。嘻嘻。
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