Java小项目--满汉楼

Java小项目–满汉楼

项目需求

在这里插入图片描述
在这里插入图片描述
在这里插入图片描述
在这里插入图片描述
在这里插入图片描述

项目实现

1.实现对工具包的编写

在这里插入图片描述
先创建libs包完成对jar包的拷贝和添加入库
德鲁伊工具包

package com.wantian.mhl.utils;import com.alibaba.druid.pool.DruidDataSourceFactory;import javax.sql.DataSource;
import java.io.FileInputStream;
import java.io.IOException;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;public class JDBCUtilsDruid {private static DataSource ds;static {Properties properties = new Properties();try {properties.load(new FileInputStream("src\\druid.properties"));ds = DruidDataSourceFactory.createDataSource(properties);} catch (Exception e) {throw new RuntimeException(e);}}public static Connection getConnection() throws SQLException {return ds.getConnection();}public static void close(ResultSet set, Statement statement,Connection connection){try {if (set != null) {set.close();}if (statement != null) {statement.close();}if (connection != null) {connection.close();}}catch (SQLException e){throw new RuntimeException();}}
}

工具包

package com.wantian.mhl.utils;/**工具类的作用:处理各种情况的用户输入，并且能够按照程序员的需求，得到用户的控制台输入。
*/import java.util.*;
/***/
public class Utility {//静态属性。。。private static Scanner scanner = new Scanner(System.in);/*** 功能：读取键盘输入的一个菜单选项，值：1——5的范围* @return 1——5*/public static char readMenuSelection() {char c;for (; ; ) {String str = readKeyBoard(1, false);//包含一个字符的字符串c = str.charAt(0);//将字符串转换成字符char类型if (c != '1' && c != '2' && c != '3' && c != '4' && c != '5') {System.out.print("选择错误，请重新输入：");} else break;}return c;}/*** 功能：读取键盘输入的一个字符* @return 一个字符*/public static char readChar() {String str = readKeyBoard(1, false);//就是一个字符return str.charAt(0);}/*** 功能：读取键盘输入的一个字符，如果直接按回车，则返回指定的默认值；否则返回输入的那个字符* @param defaultValue 指定的默认值* @return 默认值或输入的字符*/public static char readChar(char defaultValue) {String str = readKeyBoard(1, true);//要么是空字符串，要么是一个字符return (str.length() == 0) ? defaultValue : str.charAt(0);}/*** 功能：读取键盘输入的整型，长度小于2位* @return 整数*/public static int readInt() {int n;for (; ; ) {String str = readKeyBoard(2, false);//一个整数，长度<=2位try {n = Integer.parseInt(str);//将字符串转换成整数break;} catch (NumberFormatException e) {System.out.print("数字输入错误，请重新输入：");}}return n;}/*** 功能：读取键盘输入的 整数或默认值，如果直接回车，则返回默认值，否则返回输入的整数* @param defaultValue 指定的默认值* @return 整数或默认值*/public static int readInt(int defaultValue) {int n;for (; ; ) {String str = readKeyBoard(10, true);if (str.equals("")) {return defaultValue;}//异常处理...try {n = Integer.parseInt(str);break;} catch (NumberFormatException e) {System.out.print("数字输入错误，请重新输入：");}}return n;}/*** 功能：读取键盘输入的指定长度的字符串* @param limit 限制的长度* @return 指定长度的字符串*/public static String readString(int limit) {return readKeyBoard(limit, false);}/*** 功能：读取键盘输入的指定长度的字符串或默认值，如果直接回车，返回默认值，否则返回字符串* @param limit 限制的长度* @param defaultValue 指定的默认值* @return 指定长度的字符串*/public static String readString(int limit, String defaultValue) {String str = readKeyBoard(limit, true);return str.equals("")? defaultValue : str;}/*** 功能：读取键盘输入的确认选项，Y或N* 将小的功能，封装到一个方法中.* @return Y或N*/public static char readConfirmSelection() {System.out.println("请输入你的选择(Y/N)");char c;for (; ; ) {//无限循环//在这里，将接受到字符，转成了大写字母//y => Y n=>NString str = readKeyBoard(1, false).toUpperCase();c = str.charAt(0);if (c == 'Y' || c == 'N') {break;} else {System.out.print("选择错误，请重新输入：");}}return c;}/*** 功能： 读取一个字符串* @param limit 读取的长度* @param blankReturn 如果为true ,表示 可以读空字符串。 * 					  如果为false表示 不能读空字符串。* 			*	如果输入为空，或者输入大于limit的长度，就会提示重新输入。* @return*/private static String readKeyBoard(int limit, boolean blankReturn) {//定义了字符串String line = "";//scanner.hasNextLine() 判断有没有下一行while (scanner.hasNextLine()) {line = scanner.nextLine();//读取这一行//如果line.length=0, 即用户没有输入任何内容，直接回车if (line.length() == 0) {if (blankReturn) return line;//如果blankReturn=true,可以返回空串else continue; //如果blankReturn=false,不接受空串，必须输入内容}//如果用户输入的内容大于了 limit，就提示重写输入  //如果用户如的内容 >0 <= limit ,我就接受if (line.length() < 1 || line.length() > limit) {System.out.print("输入长度（不能大于" + limit + "）错误，请重新输入：");continue;}break;}return line;}
}

2.初步编写界面

package com.wantian.mhl.view;import com.wantian.mhl.utils.Utility;public class MHLView {// 控制是否退出菜单private boolean loop = true;private String key = "";public static void main(String[] args) {new MHLView().mainMenu();}//显示主菜单public void mainMenu() {while (loop) {System.out.println("==============满汉楼===============");System.out.println("\t\t 1 登录满汉楼");System.out.println("\t\t 2 退出满汉楼");System.out.println("请输入你的选择: ");key = Utility.readString(1);switch (key){case "1":System.out.print("请输入员工号: ");String id = Utility.readString(50);System.out.print("请输入密  码: ");String pwd = Utility.readString(50);//到数据库去判断if (pwd.equals("123")){System.out.println("================登录成功===============\n");//显示二级菜单while (loop){System.out.println("==============满汉楼(二级菜单)===============");System.out.println("\t\t 1 显示餐桌状态");System.out.println("\t\t 2 预订餐桌");System.out.println("\t\t 3 显示所有菜品");System.out.println("\t\t 4 点餐服务");System.out.println("\t\t 5 查看菜单");System.out.println("\t\t 6 结账");System.out.println("\t\t 9 退出满汉楼");System.out.println("请输入你的选择");key = Utility.readString(1);switch (key){case "1":System.out.println("显示餐桌状态");break;case "2":System.out.println("预订餐桌");break;case "3":System.out.println("显示所有菜品");break;case "4":System.out.println("点餐服务");break;case "5":System.out.println("查看账单");break;case "6":System.out.println("结账");break;case "9":loop = false;break;default:System.out.println("你的输入有误，请重新输入");}}}else {System.out.println("================登录失败===============\n");}break;case "2":System.out.println("退出满汉楼");loop = false;break;default:System.out.println("你输入有误，请重新输入");}}}
}

3.创建Employee表，domain（类）,EmployeeDAO和BasicDAO

创建Employee表

-- 创建满汉楼的表--
CREATE DATABASE mhl;
#用户表emplyee表(主键id,empId,name,pwd,job等)
CREATE TABLE employee (id INT PRIMARY KEY AUTO_INCREMENT, #自增empId VARCHAR(50) UNIQUE NOT NULL DEFAULT '',#员工号pwd CHAR(32) NOT NULL DEFAULT '',#密码md5NAME VARCHAR(50) NOT NULL DEFAULT '',#姓名job VARCHAR(50) NOT NULL DEFAULT '' #岗位
)CHARSET=utf8; -- 添加测试数据
INSERT INTO employee VALUES(NULL, '6668612', MD5('123456'), '张三丰', '经理');
INSERT INTO employee VALUES(NULL, '6668622', MD5('123456'),'小龙女', '服务员');
INSERT INTO employee VALUES(NULL, '6668633', MD5('123456'), '张无忌', '收银员');
INSERT INTO employee VALUES(NULL, '666', MD5('123456'), '老韩', '经理');

创建Employee类

package com.wantian.mhl.domain;/*** id INT PRIMARY KEY AUTO_INCREMENT, #自增* 	empId VARCHAR(50) NOT NULL DEFAULT '',#员工号* 	pwd CHAR(32) NOT NULL DEFAULT '',#密码md5* 	NAME VARCHAR(50) NOT NULL DEFAULT '',#姓名* 	job VARCHAR(50) NOT NULL DEFAULT '' #岗位*/
public class Employee {private Integer id;private String empId;private String pwd;private String name;private String job;public Employee() {}public Employee(Integer id, String empId, String pwd, String name, String job) {this.id = id;this.empId = empId;this.pwd = pwd;this.name = name;this.job = job;}public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getEmpId() {return empId;}public void setEmpId(String empId) {this.empId = empId;}public String getPwd() {return pwd;}public void setPwd(String pwd) {this.pwd = pwd;}public String getName() {return name;}public void setName(String name) {this.name = name;}public String getJob() {return job;}public void setJob(String job) {this.job = job;}
}

创建BasicDAO表

package com.wantian.mhl.dao;import com.wantian.mhl.utils.JDBCUtilsDruid;
import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanHandler;
import org.apache.commons.dbutils.handlers.BeanListHandler;
import org.apache.commons.dbutils.handlers.ScalarHandler;import java.sql.Connection;
import java.sql.SQLException;
import java.util.List;public class BasicDAO <T>{private QueryRunner qr = new QueryRunner();private int update(String sql,Object...parameters){Connection connection = null;try {connection= JDBCUtilsDruid.getConnection();int update = qr.update(sql, parameters);return update;} catch (SQLException e) {throw new RuntimeException(e);}finally {JDBCUtilsDruid.close(null,null,connection);}}public List<T> queryMultiply(String sql,Class<T> clazz,Object...parameters){Connection connection = null;try {connection = JDBCUtilsDruid.getConnection();List<T> query = qr.query(connection, sql, new BeanListHandler<T>(clazz), parameters);return query;} catch (SQLException e) {throw new RuntimeException(e);}finally {JDBCUtilsDruid.close(null,null,connection);}}public T querySingle(String sql,Class<T> clazz,Object...parameters){Connection connection = null;try {connection = JDBCUtilsDruid.getConnection();T query = qr.query(connection, sql, new BeanHandler<T>(clazz), parameters);return query;} catch (SQLException e) {throw new RuntimeException(e);}finally {JDBCUtilsDruid.close(null,null,connection);}}public Object queryScalar(String sql,Object...parameters){Connection connection = null;try {connection = JDBCUtilsDruid.getConnection();Object query = qr.query(connection, sql, new ScalarHandler(), parameters);return query;} catch (SQLException e) {throw new RuntimeException(e);}finally {JDBCUtilsDruid.close(null,null,connection);}}
}

创建EmployeeDAO

package com.wantian.mhl.dao;import com.wantian.mhl.domain.Employee;public class EmployeeDAO extends BasicDAO<Employee>{//这里可以写特有的操作
}

4.创建一个EmployeeService

package com.wantian.mhl.service;import com.wantian.mhl.dao.EmployeeDAO;
import com.wantian.mhl.domain.Employee;/*** 该类完成对employee表的各种业务操作*/
public class EmployeeService {//定义一个Employee属性private EmployeeDAO employeeDAO = new EmployeeDAO();//方法，根据 empId 和 pwd 返回一个Employee对象//如果查询不到，就返回一个nullpublic Employee getEmployeeByIdAndPwd(String empId,String pwd){Employee employee =employeeDAO.querySingle("select * from employee where empId = ? and pwd = md5(?)", Employee.class, empId, pwd);return employee;}
}

然后将其添加到菜单界面进行判定
这个位置

Employee employee = employeeService.getEmployeeByIdAndPwd(empId, pwd);//到数据库去判断if (employee != null){System.out.println("================登录成功["+ employee.getName() + "]===============\n");

5.创建Dining表，domain（类DiningTable），DiningTableDAO，DingTableService

创建dining表

-- 创建dining表（id，state，orderName等）
#餐桌表
CREATE TABLE diningTable (id INT PRIMARY KEY AUTO_INCREMENT, #自增, 表示餐桌编号state VARCHAR(20) NOT NULL DEFAULT '',#餐桌的状态orderName VARCHAR(50) NOT NULL DEFAULT '',#预订人的名字orderTel VARCHAR(20) NOT NULL DEFAULT ''
)CHARSET=utf8; INSERT INTO diningTable VALUES(NULL, '空','','');
INSERT INTO diningTable VALUES(NULL, '空','','');
INSERT INTO diningTable VALUES(NULL, '空','','');

创建DiningTable

package com.wantian.mhl.domain;/*** id INT PRIMARY KEY AUTO_INCREMENT, #自增, 表示餐桌编号* 	state VARCHAR(20) NOT NULL DEFAULT '',#餐桌的状态* 	orderName VARCHAR(50) NOT NULL DEFAULT '',#预订人的名字* 	orderTel VARCHAR(20) NOT NULL DEFAULT ''*/
public class DiningTable {private Integer id;private String state;private String orderName;private String orderTel;public DiningTable() {}public DiningTable(Integer id, String state, String orderName, String orderTel) {this.id = id;this.state = state;this.orderName = orderName;this.orderTel = orderTel;}public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getState() {return state;}public void setState(String state) {this.state = state;}public String getOrderName() {return orderName;}public void setOrderName(String orderName) {this.orderName = orderName;}public String getOrderTel() {return orderTel;}public void setOrderTel(String orderTel) {this.orderTel = orderTel;}@Overridepublic String toString() {return  id + "\t\t\t" + state ;}
}

创建DiningTableDAO

package com.wantian.mhl.dao;public class DiningTableDAO extends BasicDAO<DiningTable>{//如果有特殊操作可以添加
}

创建DiningTableService

package com.wantian.mhl.service;import com.wantian.mhl.dao.DiningTableDAO;
import com.wantian.mhl.domain.DiningTable;import java.util.List;public class DiningTableService {// 定义一个DiningTableDAO对象private DiningTableDAO diningTableDAO = new DiningTableDAO();public List<DiningTable> list() {List<DiningTable> diningTables = diningTableDAO.queryMultiply("select id, state from diningTable", DiningTable.class);return diningTables;}

6.完成对餐桌的预订

检测餐桌是否存在和餐桌的状态

//根据id,查询对应的餐桌DiningTable 对象//如果返回null，表示id编号对应的餐桌不存在public DiningTable getDiningTableById(int id){return diningTableDAO.querySingle("select * from diningTable where id = ?",DiningTable.class,id);}//如果餐桌可以预订,调用方法,对其状态进行更新（包括预订人的名字和电话）public boolean orderDiningTable(int id,String orderName,String orderTel){int update = diningTableDAO.update("update diningTable set state = '已经预订',orderName = ?,orderTel = ? where id = ?", orderName, orderTel, id);return update > 0;}

然后编写进入界面

public void orderDiningTable(){System.out.println("=============预订餐桌==============");System.out.println("请选择要预订餐桌的编号(-1 表示退出预订)");int orderId = Utility.readInt();if (orderId == -1){System.out.println("==============取消预订餐桌================");return;}char key = Utility.readConfirmSelection();if (key == 'Y'){// 根据orderId，返回对应DiningTable对象，如果为null，说明该对象不存在DiningTable diningTable = diningTableService.getDiningTableById(orderId);if (diningTable == null){System.out.println("餐桌不存在");return;}//判断该餐桌状态是否为“空”if(!("空".equals(diningTable.getState()))){System.out.println("==============餐桌已被预订==============");return;}//这时,得到相关信息并完成预订System.out.print("请输入预订人的名字");String orderName = Utility.readString(50);System.out.print("请输入预订人的电话：");String orderTel = Utility.readString(50);if(diningTableService.orderDiningTable(orderId,orderName,orderTel)) {System.out.println("===============预订餐桌成功==============");}else {System.out.println("===============预订餐桌失败==============");}}else {System.out.println("==================取消预订餐桌===============");}}

7.创建menu表，domain类，和MenuDAO，MenuService

创建menu表

#菜谱
create table menu (id int primary key auto_increment, #自增主键，作为菜谱编号(唯一)name varchar(50) not null default '',#菜品名称type varchar(50) not null default '', #菜品种类price double not null default 0#价格
)charset=utf8; insert into menu values(null, '八宝饭', '主食类', 10);
insert into menu values(null, '叉烧包', '主食类', 20);
insert into menu values(null, '宫保鸡丁', '热菜类', 30);
insert into menu values(null, '山药拨鱼', '凉菜类', 14);
insert into menu values(null, '银丝卷', '甜食类', 9);
insert into menu values(null, '水煮鱼', '热菜类', 26);
insert into menu values(null, '甲鱼汤', '汤类', 100);
insert into menu values(null, '鸡蛋汤', '汤类', 16);

Menu类

package com.wantian.mhl.domain;/*** id int primary key auto_increment, #自增主键，作为菜谱编号(唯一)* 	name varchar(50) not null default '',#菜品名称* 	type varchar(50) not null default '', #菜品种类* 	price double not null default 0#价格*/
public class Menu {private Integer id;private String name;private String type;private Double price;public Menu() {}public Menu(Integer id, String name, String type, Double price) {this.id = id;this.name = name;this.type = type;this.price = price;}public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public String getType() {return type;}public void setType(String type) {this.type = type;}public Double getPrice() {return price;}public void setPrice(Double price) {this.price = price;}
}

创建MenuDAO

public class MenuDAO extends BasicDAO<Menu>{//这里可以创建特殊方法
}

创建MenuService

package com.wantian.mhl.service;import com.wantian.mhl.dao.MenuDAO;
import com.wantian.mhl.domain.Menu;import java.util.List;public class MenuService {//定义MenuDAOprivate MenuDAO menuDAO = new MenuDAO();//返回所有的菜品public List<Menu> list(){return menuDAO.queryMultiply("select * from menu",Menu.class);}}

创建bill表，bill类，BillDAO，BillService

创建bill表

#账单流水, 考虑可以分开结账, 并考虑将来分别统计各个不同菜品的销售情况
create table bill (id int primary key auto_increment, #自增主键billId varchar(50) not null default '',#账单号可以按照自己规则生成 UUIDmenuId int not null default 0,#菜品的编号, 也可以使用外键nums SMALLINT not null default 0,#份数money double not null default 0, #金额diningTableId int not null default 0, #餐桌billDate datetime not null ,#订单日期state varchar(50) not null default '' # 状态 '未结账' , '已经结账', '挂单'
)charset=utf8;

创建bill类

package com.wantian.mhl.domain;import java.util.Date;/***id INT PRIMARY KEY AUTO_INCREMENT, #自增主键* 	billId VARCHAR(50) NOT NULL DEFAULT '',#账单号可以按照自己规则生成 UUID* 	menuId INT NOT NULL DEFAULT 0,#菜品的编号, 也可以使用外键* 	nums SMALLINT NOT NULL DEFAULT 0,#份数* 	money DOUBLE NOT NULL DEFAULT 0, #金额* 	diningTableId INT NOT NULL DEFAULT 0, #餐桌* 	billDate DATETIME NOT NULL ,#订单日期* 	state VARCHAR(50) NOT NULL DEFAULT '' # 状态 '未结账' , '已经结账', '挂单'*/
public class Bill {private Integer id;private String billId;private Integer menuId;private Integer numbers;private Double money;private Integer diningId;private Date billDate;private String state;public Bill() {}public Bill(Integer id, String billId, Integer menuId, Integer numbers, Double money, Integer diningId, Date billDate, String state) {this.id = id;this.billId = billId;this.menuId = menuId;this.numbers = numbers;this.money = money;this.diningId = diningId;this.billDate = billDate;this.state = state;}public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getBillId() {return billId;}public void setBillId(String billId) {this.billId = billId;}public Integer getMenuId() {return menuId;}public void setMenuId(Integer menuId) {this.menuId = menuId;}public Integer getNumbers() {return numbers;}public void setNumbers(Integer numbers) {this.numbers = numbers;}public Double getMoney() {return money;}public void setMoney(Double money) {this.money = money;}public Integer getDiningId() {return diningId;}public void setDiningId(Integer diningId) {this.diningId = diningId;}public Date getBillDate() {return billDate;}public void setBillDate(Date billDate) {this.billDate = billDate;}public String getState() {return state;}public void setState(String state) {this.state = state;}
}

创建BillDAO

package com.wantian.mhl.dao;import com.wantian.mhl.domain.Bill;public class BillDAO extends BasicDAO<Bill>{//这里可以进行特殊方法的添加
}

进行BillService编写

package com.wantian.mhl.service;import com.wantian.mhl.dao.BasicDAO;
import com.wantian.mhl.dao.BillDAO;
import com.wantian.mhl.domain.Menu;import java.util.UUID;public class BillService {// 定义BillDAO属性private BillDAO billDAO = new BillDAO();// 定义MenuServiceprivate MenuService menuService = new MenuService();// 定义DiningTableServiceprivate DiningTableService diningTableService = new DiningTableService();// 编写点餐的方法// 1.生成菜单// 2.需要更新餐桌的状态public boolean orderMenu(int menuId,int numbers,int diningTableId){// 生成一个账单号,UUIDString billId = UUID.randomUUID().toString();// 将账单生成到bill表// 需要计算账单金额int update = billDAO.update("insert into bill values(null,?,?,?,?,?,now(),'未结账')", billId, menuId, numbers, menuService.getMenuById(menuId).getPrice() * numbers, diningTableId);if(update <= 0){return false;}return diningTableService.updateDiningTableState(diningTableId,"就餐中");}}

这里在其它的如DiningTableService里，增加了特殊方法，来设置状态

public boolean updateDiningTableState(int id,String state){int update = diningTableDAO.update("update diningTable set state = ? where id = ?", state, id);return update > 0;}

编写界面和判断数据是否合理

public void orderMenu(){System.out.println("================点餐服务==============");System.out.print("请输入点餐的桌号(-1退出):");int orderDiningTableId = Utility.readInt();if (orderDiningTableId == -1){System.out.println("=============取消点餐=============");return;}System.out.println("请输入点餐的菜品号(-1退出): ");int orderMenuId = Utility.readInt();if (orderMenuId == -1){System.out.println("=============取消点餐=============");return;}System.out.println("请输入点餐的菜品量(-1退出): ");int orderNumbers = Utility.readInt();if (orderNumbers == -1){System.out.println("=============取消点餐=============");return;}// 验证数据是否存在(餐桌)DiningTable diningTable = diningTableService.getDiningTableById(orderDiningTableId);if (diningTable == null){System.out.println("===============餐桌不存在==============");return;}// 验证菜品编号Menu menu = menuService.getMenuById(orderMenuId);if (menu == null){System.out.println("===============菜品不存在===============");return;}if(billService.orderMenu(orderMenuId,orderNumbers,orderDiningTableId)){System.out.println("===============点餐成功=================");}else {System.out.println("===============点餐失败=================");}}

返回查询账单

public void listBill(){List<Bill> bills = billService.list();System.out.println("\n编号\t\t菜品号\t\t菜品量\t\t金额\t\t桌号\t\t日期\t\t\t\t\t\t\t状态");for (Bill bill : bills) {System.out.println(bill);}System.out.println("===============显示完毕===============");}

实现结账

编写设置状态的方法

public boolean updateDiningTableToFree(int id,String state){int update = diningTableDAO.update("update diningTable set state = ? ,orderName = ' ', orderTel = ' ',where id = ?", state, id);return update > 0;}

编写提交账单方法

public boolean payBill(int diningTableId,String payMode) {// 1. 修改bill表int update = billDAO.update("update bill set state = ? where diningTableId = ? and state = '未结账'", payMode, diningTableId);if (update <= 0){return false;}//如果更新没有成功，表示失败// 2. 修改diningTable表if (!diningTableService.updateDiningTableToFree(diningTableId,"空")){return false;}return true;}

界面编写结账

public void payBill(){System.out.println("================结账服务===============");System.out.print("请选择要结账的餐桌编号(-1退出)： ");int diningTableId = Utility.readInt();if (diningTableId == -1){System.out.println("==============取消结账=============");return;}// 验证餐桌是否存在DiningTable diningTable = diningTableService.getDiningTableById(diningTableId);if (diningTable == null){System.out.println("================餐桌不存在=================");return;}// 验证该餐桌账单是否存在if (!(billService.hasPayBillByDiningTableId(diningTableId))){System.out.println("================已经结账了================");return;}System.out.print("请选择要结账的方式(现金/支付宝/微信)(回车表示退出)");String payMode = Utility.readString(20,"");// 如果回车，返回空串if ("".equals(payMode)){System.out.println("===============取消结账==============");return;}char key = Utility.readConfirmSelection();if (key == 'Y'){// 完成结账if (billService.payBill(diningTableId,payMode)){System.out.println("================完成结账================");}else {System.out.println("================结账失败================");}}else {System.out.println("================取消结账===============");}}

完成一个多表映射

完成多表账单的编写

package com.wantian.mhl.domain;import java.util.Date;public class MultiTableBean {// 和多张表进行映射private Integer id;private String billId;private Integer menuId;private Integer nums;private Double money;private Integer diningTableId;private Date billDate;private String state;
// 增加一个来自menu表的列，nameprivate String name;public MultiTableBean() {}public MultiTableBean(Integer id, String billId, Integer menuId, Integer nums, Double money, Integer diningTableId, Date billDate, String state, String name) {this.id = id;this.billId = billId;this.menuId = menuId;this.nums = nums;this.money = money;this.diningTableId = diningTableId;this.billDate = billDate;this.state = state;this.name = name;}public String getName() {return name;}public void setName(String name) {this.name = name;}public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getBillId() {return billId;}public void setBillId(String billId) {this.billId = billId;}public Integer getMenuId() {return menuId;}public void setMenuId(Integer menuId) {this.menuId = menuId;}public Integer getNumbers() {return nums;}public void setNumbers(Integer numbers) {this.nums = numbers;}public Double getMoney() {return money;}public void setMoney(Double money) {this.money = money;}public Integer getDiningId() {return diningTableId;}public void setDiningId(Integer diningId) {this.diningTableId = diningId;}public Date getBillDate() {return billDate;}public void setBillDate(Date billDate) {this.billDate = billDate;}public String getState() {return state;}public void setState(String state) {this.state = state;}public Integer getNums() {return nums;}public void setNums(Integer nums) {this.nums = nums;}public Integer getDiningTableId() {return diningTableId;}public void setDiningTableId(Integer diningTableId) {this.diningTableId = diningTableId;}@Overridepublic String toString() {return  id +"\t\t" + menuId +"\t\t\t" + nums +"\t\t\t" + money +"\t" + diningTableId +"\t\t" + billDate +"\t\t" + state +"\t\t" + name;}
}

完成对返回账单的升级（多表查询）

public void listBill() {
//        List<Bill> bills = billService.list();
//        System.out.println("\n编号\t\t菜品号\t\t菜品量\t\t金额\t\t桌号\t\t日期\t\t\t\t\t\t\t状态");
//        for (Bill bill : bills) {
//            System.out.println(bill);
//        }
//        System.out.println("===============显示完毕===============");List<MultiTableBean> multiTableBeans = billService.list2();System.out.println("\n编号\t\t菜品号\t\t菜品量\t\t金额\t\t桌号\t\t日期\t\t\t\t\t\t\t状态\t\t菜品名");for (MultiTableBean multiTableBean : multiTableBeans) {System.out.println(multiTableBean);}}

view

package com.wantian.mhl.view;import com.wantian.mhl.domain.*;
import com.wantian.mhl.service.BillService;
import com.wantian.mhl.service.DiningTableService;
import com.wantian.mhl.service.EmployeeService;
import com.wantian.mhl.service.MenuService;
import com.wantian.mhl.utils.Utility;import java.util.List;public class MHLView {// 控制是否退出菜单private boolean loop = true;private String key = "";private EmployeeService employeeService = new EmployeeService();private DiningTableService diningTableService = new DiningTableService();private MenuService menuService = new MenuService();private BillService billService = new BillService();public static void main(String[] args) {new MHLView().mainMenu();}//显示主菜单public void mainMenu() {while (loop) {System.out.println("==============满汉楼===============");System.out.println("\t\t 1 登录满汉楼");System.out.println("\t\t 2 退出满汉楼");System.out.println("请输入你的选择: ");key = Utility.readString(1);switch (key){case "1":System.out.print("请输入员工号: ");String empId = Utility.readString(50);System.out.print("请输入密  码: ");String pwd = Utility.readString(50);Employee employee = employeeService.getEmployeeByIdAndPwd(empId, pwd);//到数据库去判断if (employee != null){System.out.println("================登录成功["+ employee.getName() + "]===============\n");//显示二级菜单while (loop){System.out.println("==============满汉楼(二级菜单)===============");System.out.println("\t\t 1 显示餐桌状态");System.out.println("\t\t 2 预订餐桌");System.out.println("\t\t 3 显示所有菜品");System.out.println("\t\t 4 点餐服务");System.out.println("\t\t 5 查看账单");System.out.println("\t\t 6 结账");System.out.println("\t\t 9 退出满汉楼");System.out.println("请输入你的选择");key = Utility.readString(1);switch (key){case "1":listDiningTable();break;case "2":orderDiningTable();break;case "3":listMenu();break;case "4":orderMenu();break;case "5":listBill();break;case "6":payBill();break;case "9":loop = false;break;default:System.out.println("你的输入有误，请重新输入");}}}else {System.out.println("================登录失败===============\n");}break;case "2":System.out.println("退出满汉楼");loop = false;break;default:System.out.println("你输入有误，请重新输入");}}}//显示所有菜品public void listMenu(){List<Menu> list = menuService.list();System.out.println("\n菜品编号\t\t菜品名\t\t类别\t\t\t价格");for (Menu menu : list) {System.out.println(menu);}System.out.println("================显示完毕===============");}// 显示所有餐桌状态public void listDiningTable(){List<DiningTable> list = diningTableService.list();System.out.println("\n餐桌编号\t\t餐桌状态");for (DiningTable diningTable : list) {System.out.println(diningTable);}System.out.println("==============显示完毕==============");}// 完成预订餐桌public void orderDiningTable(){System.out.println("=============预订餐桌==============");System.out.println("请选择要预订餐桌的编号(-1 表示退出预订)");int orderId = Utility.readInt();if (orderId == -1){System.out.println("==============取消预订餐桌================");return;}char key = Utility.readConfirmSelection();if (key == 'Y'){// 根据orderId，返回对应DiningTable对象，如果为null，说明该对象不存在DiningTable diningTable = diningTableService.getDiningTableById(orderId);if (diningTable == null){System.out.println("餐桌不存在");return;}//判断该餐桌状态是否为“空”if(!("空".equals(diningTable.getState()))){System.out.println("==============餐桌已被预订==============");return;}//这时,得到相关信息并完成预订System.out.print("请输入预订人的名字");String orderName = Utility.readString(50);System.out.print("请输入预订人的电话：");String orderTel = Utility.readString(50);if(diningTableService.orderDiningTable(orderId,orderName,orderTel)) {System.out.println("===============预订餐桌成功==============");}else {System.out.println("===============预订餐桌失败==============");}}else {System.out.println("==================取消预订餐桌===============");}}// 完成点餐public void orderMenu(){System.out.println("================点餐服务==============");System.out.print("请输入点餐的桌号(-1退出):");int orderDiningTableId = Utility.readInt();if (orderDiningTableId == -1){System.out.println("=============取消点餐=============");return;}System.out.println("请输入点餐的菜品号(-1退出): ");int orderMenuId = Utility.readInt();if (orderMenuId == -1){System.out.println("=============取消点餐=============");return;}System.out.println("请输入点餐的菜品量(-1退出): ");int orderNumbers = Utility.readInt();if (orderNumbers == -1){System.out.println("=============取消点餐=============");return;}// 验证数据是否存在(餐桌)DiningTable diningTable = diningTableService.getDiningTableById(orderDiningTableId);if (diningTable == null){System.out.println("===============餐桌不存在==============");return;}// 验证菜品编号Menu menu = menuService.getMenuById(orderMenuId);if (menu == null){System.out.println("===============菜品不存在===============");return;}if(billService.orderMenu(orderMenuId,orderNumbers,orderDiningTableId)){System.out.println("===============点餐成功=================");}else {System.out.println("===============点餐失败=================");}}// 显示账单信息public void listBill() {
//        List<Bill> bills = billService.list();
//        System.out.println("\n编号\t\t菜品号\t\t菜品量\t\t金额\t\t桌号\t\t日期\t\t\t\t\t\t\t状态");
//        for (Bill bill : bills) {
//            System.out.println(bill);
//        }
//        System.out.println("===============显示完毕===============");List<MultiTableBean> multiTableBeans = billService.list2();System.out.println("\n编号\t\t菜品号\t\t菜品量\t\t金额\t\t桌号\t\t日期\t\t\t\t\t\t\t状态\t\t菜品名\t\t价格");for (MultiTableBean multiTableBean : multiTableBeans) {System.out.println(multiTableBean);}}// 完成结账public void payBill(){System.out.println("================结账服务===============");System.out.print("请选择要结账的餐桌编号(-1退出)： ");int diningTableId = Utility.readInt();if (diningTableId == -1){System.out.println("==============取消结账=============");return;}// 验证餐桌是否存在DiningTable diningTable = diningTableService.getDiningTableById(diningTableId);if (diningTable == null){System.out.println("================餐桌不存在=================");return;}// 验证该餐桌账单是否存在if (!(billService.hasPayBillByDiningTableId(diningTableId))){System.out.println("================已经结账了================");return;}System.out.print("请选择要结账的方式(现金/支付宝/微信)(回车表示退出)");String payMode = Utility.readString(20,"");// 如果回车，返回空串if ("".equals(payMode)){System.out.println("===============取消结账==============");return;}char key = Utility.readConfirmSelection();if (key == 'Y'){// 完成结账if (billService.payBill(diningTableId,payMode)){System.out.println("================完成结账================");}else {System.out.println("================结账失败================");}}else {System.out.println("================取消结账===============");}}
}

Utils

Utility

package com.wantian.mhl.utils;/**工具类的作用:处理各种情况的用户输入，并且能够按照程序员的需求，得到用户的控制台输入。
*/import java.util.*;
/***/
public class Utility {//静态属性。。。private static Scanner scanner = new Scanner(System.in);/*** 功能：读取键盘输入的一个菜单选项，值：1——5的范围* @return 1——5*/public static char readMenuSelection() {char c;for (; ; ) {String str = readKeyBoard(1, false);//包含一个字符的字符串c = str.charAt(0);//将字符串转换成字符char类型if (c != '1' && c != '2' && c != '3' && c != '4' && c != '5') {System.out.print("选择错误，请重新输入：");} else break;}return c;}/*** 功能：读取键盘输入的一个字符* @return 一个字符*/public static char readChar() {String str = readKeyBoard(1, false);//就是一个字符return str.charAt(0);}/*** 功能：读取键盘输入的一个字符，如果直接按回车，则返回指定的默认值；否则返回输入的那个字符* @param defaultValue 指定的默认值* @return 默认值或输入的字符*/public static char readChar(char defaultValue) {String str = readKeyBoard(1, true);//要么是空字符串，要么是一个字符return (str.length() == 0) ? defaultValue : str.charAt(0);}/*** 功能：读取键盘输入的整型，长度小于2位* @return 整数*/public static int readInt() {int n;for (; ; ) {String str = readKeyBoard(2, false);//一个整数，长度<=2位try {n = Integer.parseInt(str);//将字符串转换成整数break;} catch (NumberFormatException e) {System.out.print("数字输入错误，请重新输入：");}}return n;}/*** 功能：读取键盘输入的 整数或默认值，如果直接回车，则返回默认值，否则返回输入的整数* @param defaultValue 指定的默认值* @return 整数或默认值*/public static int readInt(int defaultValue) {int n;for (; ; ) {String str = readKeyBoard(10, true);if (str.equals("")) {return defaultValue;}//异常处理...try {n = Integer.parseInt(str);break;} catch (NumberFormatException e) {System.out.print("数字输入错误，请重新输入：");}}return n;}/*** 功能：读取键盘输入的指定长度的字符串* @param limit 限制的长度* @return 指定长度的字符串*/public static String readString(int limit) {return readKeyBoard(limit, false);}/*** 功能：读取键盘输入的指定长度的字符串或默认值，如果直接回车，返回默认值，否则返回字符串* @param limit 限制的长度* @param defaultValue 指定的默认值* @return 指定长度的字符串*/public static String readString(int limit, String defaultValue) {String str = readKeyBoard(limit, true);return str.equals("")? defaultValue : str;}/*** 功能：读取键盘输入的确认选项，Y或N* 将小的功能，封装到一个方法中.* @return Y或N*/public static char readConfirmSelection() {System.out.println("请输入你的选择(Y/N)");char c;for (; ; ) {//无限循环//在这里，将接受到字符，转成了大写字母//y => Y n=>NString str = readKeyBoard(1, false).toUpperCase();c = str.charAt(0);if (c == 'Y' || c == 'N') {break;} else {System.out.print("选择错误，请重新输入：");}}return c;}/*** 功能： 读取一个字符串* @param limit 读取的长度* @param blankReturn 如果为true ,表示 可以读空字符串。 * 					  如果为false表示 不能读空字符串。* 			*	如果输入为空，或者输入大于limit的长度，就会提示重新输入。* @return*/private static String readKeyBoard(int limit, boolean blankReturn) {//定义了字符串String line = "";//scanner.hasNextLine() 判断有没有下一行while (scanner.hasNextLine()) {line = scanner.nextLine();//读取这一行//如果line.length=0, 即用户没有输入任何内容，直接回车if (line.length() == 0) {if (blankReturn) return line;//如果blankReturn=true,可以返回空串else continue; //如果blankReturn=false,不接受空串，必须输入内容}//如果用户输入的内容大于了 limit，就提示重写输入  //如果用户如的内容 >0 <= limit ,我就接受if (line.length() < 1 || line.length() > limit) {System.out.print("输入长度（不能大于" + limit + "）错误，请重新输入：");continue;}break;}return line;}
}

JDBCUtilsDruid

package com.wantian.mhl.utils;import com.alibaba.druid.pool.DruidDataSourceFactory;import javax.sql.DataSource;
import java.io.FileInputStream;
import java.io.IOException;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;public class JDBCUtilsDruid {private static DataSource ds;static {Properties properties = new Properties();try {properties.load(new FileInputStream("src\\druid.properties"));ds = DruidDataSourceFactory.createDataSource(properties);} catch (Exception e) {throw new RuntimeException(e);}}public static Connection getConnection() throws SQLException {return ds.getConnection();}public static void close(ResultSet set, Statement statement,Connection connection){try {if (set != null) {set.close();}if (statement != null) {statement.close();}if (connection != null) {connection.close();}}catch (SQLException e){throw new RuntimeException();}}
}

Service

BillService

package com.wantian.mhl.service;import com.wantian.mhl.dao.BasicDAO;
import com.wantian.mhl.dao.BillDAO;
import com.wantian.mhl.dao.MultiTableDAO;
import com.wantian.mhl.domain.Bill;
import com.wantian.mhl.domain.Menu;
import com.wantian.mhl.domain.MultiTableBean;import java.util.List;
import java.util.UUID;public class BillService {// 定义BillDAO属性private BillDAO billDAO = new BillDAO();// 定义MenuServiceprivate MenuService menuService = new MenuService();private MultiTableDAO multiTableDAO = new MultiTableDAO();// 定义DiningTableServiceprivate DiningTableService diningTableService = new DiningTableService();// 编写点餐的方法// 1.生成菜单// 2.需要更新餐桌的状态public boolean orderMenu(int menuId,int numbers,int diningTableId){// 生成一个账单号,UUIDString billId = UUID.randomUUID().toString();// 将账单生成到bill表// 需要计算账单金额int update = billDAO.update("insert into bill values(null,?,?,?,?,?,now(),'未结账')", billId, menuId, numbers, menuService.getMenuById(menuId).getPrice() * numbers, diningTableId);if(update <= 0){return false;}return diningTableService.updateDiningTableState(diningTableId,"就餐中");}// 返回所有的账单，提供给View调用public List<Bill> list(){return billDAO.queryMultiply("select * from bill",Bill.class);}public List<MultiTableBean> list2(){return multiTableDAO.queryMultiply("select bill.*,`name` ,price from bill,menu where bill.menuId = menu.id",MultiTableBean.class);}// 返回所有的账单，并带有菜品名// 查看某张餐桌是否有未结账的账单public boolean hasPayBillByDiningTableId(int diningTableId){Bill bill = billDAO.querySingle("select * from bill where diningTableId = ? and state = '未结账' limit 0 ,1", Bill.class, diningTableId);return bill != null;}// 如果餐桌存在，且未结账,就完成结账public boolean payBill(int diningTableId,String payMode) {// 1. 修改bill表int update = billDAO.update("update bill set state = ? where diningTableId = ? and state = '未结账'", payMode, diningTableId);if (update <= 0){return false;}//如果更新没有成功，表示失败// 2. 修改diningTable表if (!diningTableService.updateDiningTableToFree(diningTableId,"空")){return false;}return true;}
}

DiningTableService

package com.wantian.mhl.service;import com.wantian.mhl.dao.DiningTableDAO;
import com.wantian.mhl.domain.DiningTable;import java.util.List;public class DiningTableService {// 定义一个DiningTableDAO对象private DiningTableDAO diningTableDAO = new DiningTableDAO();public List<DiningTable> list() {List<DiningTable> diningTables = diningTableDAO.queryMultiply("select id, state from diningTable", DiningTable.class);return diningTables;}//根据id,查询对应的餐桌DiningTable 对象//如果返回null，表示id编号对应的餐桌不存在public DiningTable getDiningTableById(int id){return diningTableDAO.querySingle("select * from diningTable where id = ?",DiningTable.class,id);}//如果餐桌可以预订,调用方法,对其状态进行更新（包括预订人的名字和电话）public boolean orderDiningTable(int id,String orderName,String orderTel){int update = diningTableDAO.update("update diningTable set state = '已经预订',orderName = ?,orderTel = ? where id = ?", orderName, orderTel, id);return update > 0;}// 需要一个更新餐桌状态的方法public boolean updateDiningTableState(int id,String state){int update = diningTableDAO.update("update diningTable set state = ? where id = ?", state, id);return update > 0;}public boolean updateDiningTableToFree(int id,String state){int update = diningTableDAO.update("update diningTable set state = ? ,orderName = ' ', orderTel = ' ' where id = ?", state, id);return update > 0;}
}

EmployeeService

package com.wantian.mhl.service;import com.wantian.mhl.dao.EmployeeDAO;
import com.wantian.mhl.domain.Employee;/*** 该类完成对employee表的各种业务操作*/
public class EmployeeService {//定义一个Employee属性private EmployeeDAO employeeDAO = new EmployeeDAO();//方法，根据 empId 和 pwd 返回一个Employee对象//如果查询不到，就返回一个nullpublic Employee getEmployeeByIdAndPwd(String empId,String pwd){Employee employee =employeeDAO.querySingle("select * from employee where empId = ? and pwd = md5(?)", Employee.class, empId, pwd);return employee;}
}

MenuService

package com.wantian.mhl.service;import com.wantian.mhl.dao.MenuDAO;
import com.wantian.mhl.domain.Menu;import java.util.List;public class MenuService {//定义MenuDAOprivate MenuDAO menuDAO = new MenuDAO();//返回所有的菜品public List<Menu> list(){return menuDAO.queryMultiply("select * from menu",Menu.class);}// 需要方法，根据id返回Menu对象public Menu getMenuById(int id){return menuDAO.querySingle("select * from menu where id = ?", Menu.class,id);}}

domain

Bill

package com.wantian.mhl.domain;import java.util.Date;/***id INT PRIMARY KEY AUTO_INCREMENT, #自增主键* 	billId VARCHAR(50) NOT NULL DEFAULT '',#账单号可以按照自己规则生成 UUID* 	menuId INT NOT NULL DEFAULT 0,#菜品的编号, 也可以使用外键* 	nums SMALLINT NOT NULL DEFAULT 0,#份数* 	money DOUBLE NOT NULL DEFAULT 0, #金额* 	diningTableId INT NOT NULL DEFAULT 0, #餐桌* 	billDate DATETIME NOT NULL ,#订单日期* 	state VARCHAR(50) NOT NULL DEFAULT '' # 状态 '未结账' , '已经结账', '挂单'*/
public class Bill {private Integer id;private String billId;private Integer menuId;private Integer nums;private Double money;private Integer diningTableId;private Date billDate;private String state;public Bill() {}public Bill(Integer id, String billId, Integer menuId, Integer numbers, Double money, Integer diningId, Date billDate, String state) {this.id = id;this.billId = billId;this.menuId = menuId;this.nums = numbers;this.money = money;this.diningTableId = diningId;this.billDate = billDate;this.state = state;}public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getBillId() {return billId;}public void setBillId(String billId) {this.billId = billId;}public Integer getMenuId() {return menuId;}public void setMenuId(Integer menuId) {this.menuId = menuId;}public Integer getNumbers() {return nums;}public void setNumbers(Integer numbers) {this.nums = numbers;}public Double getMoney() {return money;}public void setMoney(Double money) {this.money = money;}public Integer getDiningId() {return diningTableId;}public void setDiningId(Integer diningId) {this.diningTableId = diningId;}public Date getBillDate() {return billDate;}public void setBillDate(Date billDate) {this.billDate = billDate;}public String getState() {return state;}public void setState(String state) {this.state = state;}public Integer getNums() {return nums;}public void setNums(Integer nums) {this.nums = nums;}public Integer getDiningTableId() {return diningTableId;}public void setDiningTableId(Integer diningTableId) {this.diningTableId = diningTableId;}@Overridepublic String toString() {return  id +"\t\t" + menuId +"\t\t\t" + nums +"\t\t\t" + money +"\t" + diningTableId +"\t\t" + billDate +"\t\t" + state;}
}

DiningTable

package com.wantian.mhl.domain;/*** id INT PRIMARY KEY AUTO_INCREMENT, #自增, 表示餐桌编号* 	state VARCHAR(20) NOT NULL DEFAULT '',#餐桌的状态* 	orderName VARCHAR(50) NOT NULL DEFAULT '',#预订人的名字* 	orderTel VARCHAR(20) NOT NULL DEFAULT ''*/
public class DiningTable {private Integer id;private String state;private String orderName;private String orderTel;public DiningTable() {}public DiningTable(Integer id, String state, String orderName, String orderTel) {this.id = id;this.state = state;this.orderName = orderName;this.orderTel = orderTel;}public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getState() {return state;}public void setState(String state) {this.state = state;}public String getOrderName() {return orderName;}public void setOrderName(String orderName) {this.orderName = orderName;}public String getOrderTel() {return orderTel;}public void setOrderTel(String orderTel) {this.orderTel = orderTel;}@Overridepublic String toString() {return  id + "\t\t\t" + state ;}

Employee

package com.wantian.mhl.domain;/*** id INT PRIMARY KEY AUTO_INCREMENT, #自增* 	empId VARCHAR(50) NOT NULL DEFAULT '',#员工号* 	pwd CHAR(32) NOT NULL DEFAULT '',#密码md5* 	NAME VARCHAR(50) NOT NULL DEFAULT '',#姓名* 	job VARCHAR(50) NOT NULL DEFAULT '' #岗位*/
public class Employee {private Integer id;private String empId;private String pwd;private String name;private String job;public Employee() {}public Employee(Integer id, String empId, String pwd, String name, String job) {this.id = id;this.empId = empId;this.pwd = pwd;this.name = name;this.job = job;}public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getEmpId() {return empId;}public void setEmpId(String empId) {this.empId = empId;}public String getPwd() {return pwd;}public void setPwd(String pwd) {this.pwd = pwd;}public String getName() {return name;}public void setName(String name) {this.name = name;}public String getJob() {return job;}public void setJob(String job) {this.job = job;}
}

Menu

package com.wantian.mhl.domain;/*** id int primary key auto_increment, #自增主键，作为菜谱编号(唯一)* 	name varchar(50) not null default '',#菜品名称* 	type varchar(50) not null default '', #菜品种类* 	price double not null default 0#价格*/
public class Menu {private Integer id;private String name;private String type;private Double price;public Menu() {}public Menu(Integer id, String name, String type, Double price) {this.id = id;this.name = name;this.type = type;this.price = price;}public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public String getType() {return type;}public void setType(String type) {this.type = type;}public Double getPrice() {return price;}public void setPrice(Double price) {this.price = price;}@Overridepublic String toString() {return id + "\t\t\t" + name + "\t\t" + type + "\t\t" + price;}
}

MultiTableBean

package com.wantian.mhl.domain;import java.util.Date;public class MultiTableBean {// 和多张表进行映射private Integer id;private String billId;private Integer menuId;private Integer nums;private Double money;private Integer diningTableId;private Date billDate;private String state;
// 增加一个来自menu表的列，nameprivate String name;private Double price;public MultiTableBean(Integer id, String billId, Integer menuId, Integer nums, Double money, Integer diningTableId, Date billDate, String state, String name, Double price) {this.id = id;this.billId = billId;this.menuId = menuId;this.nums = nums;this.money = money;this.diningTableId = diningTableId;this.billDate = billDate;this.state = state;this.name = name;this.price = price;}public MultiTableBean() {}public MultiTableBean(Integer id, String billId, Integer menuId, Integer nums, Double money, Integer diningTableId, Date billDate, String state, String name) {this.id = id;this.billId = billId;this.menuId = menuId;this.nums = nums;this.money = money;this.diningTableId = diningTableId;this.billDate = billDate;this.state = state;this.name = name;}public Double getPrice() {return price;}public void setPrice(Double price) {this.price = price;}public String getName() {return name;}public void setName(String name) {this.name = name;}public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getBillId() {return billId;}public void setBillId(String billId) {this.billId = billId;}public Integer getMenuId() {return menuId;}public void setMenuId(Integer menuId) {this.menuId = menuId;}public Integer getNumbers() {return nums;}public void setNumbers(Integer numbers) {this.nums = numbers;}public Double getMoney() {return money;}public void setMoney(Double money) {this.money = money;}public Integer getDiningId() {return diningTableId;}public void setDiningId(Integer diningId) {this.diningTableId = diningId;}public Date getBillDate() {return billDate;}public void setBillDate(Date billDate) {this.billDate = billDate;}public String getState() {return state;}public void setState(String state) {this.state = state;}public Integer getNums() {return nums;}public void setNums(Integer nums) {this.nums = nums;}public Integer getDiningTableId() {return diningTableId;}public void setDiningTableId(Integer diningTableId) {this.diningTableId = diningTableId;}@Overridepublic String toString() {return  id +"\t\t" + menuId +"\t\t\t" + nums +"\t\t\t" + money +"\t" + diningTableId +"\t\t" + billDate +"\t\t" + state +"\t\t" + name +"\t\t" + price;}
}

DAO

BasicDAO

package com.wantian.mhl.dao;import com.wantian.mhl.domain.DiningTable;
import com.wantian.mhl.utils.JDBCUtilsDruid;
import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanHandler;
import org.apache.commons.dbutils.handlers.BeanListHandler;
import org.apache.commons.dbutils.handlers.ScalarHandler;import java.sql.Connection;
import java.sql.SQLException;
import java.util.List;public class BasicDAO <T>{private QueryRunner qr = new QueryRunner();public int update(String sql,Object...parameters){Connection connection = null;try {connection= JDBCUtilsDruid.getConnection();int update = qr.update(connection,sql, parameters);return update;} catch (SQLException e) {throw new RuntimeException(e);}finally {JDBCUtilsDruid.close(null,null,connection);}}public List<T> queryMultiply(String sql, Class<T> clazz, Object...parameters){Connection connection = null;try {connection = JDBCUtilsDruid.getConnection();List<T> query = qr.query(connection, sql, new BeanListHandler<T>(clazz), parameters);return query;} catch (SQLException e) {throw new RuntimeException(e);}finally {JDBCUtilsDruid.close(null,null,connection);}}public T querySingle(String sql,Class<T> clazz,Object...parameters){Connection connection = null;try {connection = JDBCUtilsDruid.getConnection();T query = qr.query(connection, sql, new BeanHandler<T>(clazz), parameters);return query;} catch (SQLException e) {throw new RuntimeException(e);}finally {JDBCUtilsDruid.close(null,null,connection);}}public Object queryScalar(String sql,Object...parameters){Connection connection = null;try {connection = JDBCUtilsDruid.getConnection();Object query = qr.query(connection, sql, new ScalarHandler(), parameters);return query;} catch (SQLException e) {throw new RuntimeException(e);}finally {JDBCUtilsDruid.close(null,null,connection);}}
}

BillDAO

package com.wantian.mhl.dao;import com.wantian.mhl.domain.Bill;public class BillDAO extends BasicDAO<Bill>{//这里可以进行特殊方法的添加
}

DiningTableDAO

package com.wantian.mhl.dao;import com.wantian.mhl.domain.DiningTable;public class DiningTableDAO extends BasicDAO<DiningTable>{//如果有特殊操作可以添加}

EmployeeDAO

package com.wantian.mhl.dao;import com.wantian.mhl.domain.Employee;public class EmployeeDAO extends BasicDAO<Employee>{//这里可以写特有的操作
}

MenuDAO

package com.wantian.mhl.dao;import com.wantian.mhl.domain.Menu;public class MenuDAO extends BasicDAO<Menu>{//这里可以创建特殊方法
}

MuItiTableDAO

package com.wantian.mhl.dao;import com.wantian.mhl.domain.MultiTableBean;public class MultiTableDAO extends BasicDAO<MultiTableBean>{}

本文来自互联网用户投稿，该文观点仅代表作者本人，不代表本站立场。本站仅提供信息存储空间服务，不拥有所有权，不承担相关法律责任。如若转载，请注明出处：http://www.rhkb.cn/news/281204.html

如若内容造成侵权/违法违规/事实不符，请联系长河编程网进行投诉反馈email:809451989@qq.com，一经查实，立即删除！

相关文章

C# 设置AutoScroll为true没效果的原因分析和解决办法

C# 设置AutoScroll为true没效果的原因分析和解决办法

C#中添加tabControl 分页&#xff0c;将autoscroll设置为true发现缩小窗口没有滚动条效果。该问题出现后&#xff0c;检索发现也有很多人询问了该问题&#xff0c;但是都没有给出解决方案。 原因是内部button的属性Anchor设置为top、left、right、bottom导致的缩小界面窗口也没…
阅读更多...
QT_day2:2024/3/21

QT_day2:2024/3/21

作业1&#xff1a;使用QT完成一个登录界面 要求&#xff1a; 1. 需要使用Ui界面文件进行界面设计 2. ui界面上的组件相关设置&#xff0c;通过代码实现 3. 需要添加适当的动图 源代码&#xff1a; #include "widget.h" #include "ui_widget.h"Widget…
阅读更多...
数据结构:链式二叉树

数据结构:链式二叉树

对于二叉树而言,如果不是完全二叉树,就不再适合用数组存储了 在任意二叉树中&#xff0c;度为0的节点都比度为2的节点多1个&#xff0c;即 n0 n2 1 二叉树结构 typedef struct BinTreeNode {int val;struct BinTreeNode* left;struct BinTreeNode* right; }BTNode; 二叉树…
阅读更多...
MySQL高级学习笔记

MySQL高级学习笔记

1、MySQL架构组成 1.1 高级MySQL介绍 什么是DBA&#xff1f; 数据库管理员&#xff0c;英文是Database Administrator&#xff0c;简称DBA&#xff1b; 百度百科介绍 数据库管理员&#xff08;简称DBA&#xff09;&#xff0c;是从事管理和维护数据库管理系统&#xff08;D…
阅读更多...
算法系列--递归

算法系列--递归

一.如何理解递归 递归对于初学者来说是一个非常抽象的概念,笔者在第一次学习时也是迷迷糊糊的(二叉树遍历),递归的代码看起来非常的简洁,优美,但是如何想出来递归的思路或者为什么能用递归这是初学者很难分析出来的 笔者在学习的过程中通过刷题,也总结出自己的一些经验,总结来…
阅读更多...
【什么是Internet？网络边缘，网络核心，分组交换 vs 电路交换，接入网络和物理媒体】

【什么是Internet？网络边缘，网络核心，分组交换 vs 电路交换，接入网络和物理媒体】

文章目录 一、什么是Internet&#xff1f;1.从具体构成角度来看2.从服务角度来看 二、网络结构1.网络边缘1.网络边缘&#xff1a;采用网络设施的面向连接服务1.1.目标&#xff1a;在端系统之间传输数据1.2.TCP服务 2.网络边缘&#xff1a;采用网络设施的无连接服务2.1目标&…
阅读更多...
探讨Java代码混淆加固工具

探讨Java代码混淆加固工具

摘要 本篇博客将介绍几种常用的Java代码混淆工具&#xff0c;如ProGuard、Allatori Java Obfuscator、VirboxProtector、ipaguard和DashO。我们将深入探讨它们的特点、功能以及在保护Java应用程序安全方面的作用。此外&#xff0c;还将强调在使用Java代码混淆工具时需要注意的…
阅读更多...
openssl3.2 - note - Decoders and Encoders with OpenSSL

openssl3.2 - note - Decoders and Encoders with OpenSSL

文章目录 openssl3.2 - note - Decoders and Encoders with OpenSSL概述笔记编码器/解码器的调用链OSSL_STORE 编码器/解码器的名称和属性OSSL_FUNC_decoder_freectx_fnOSSL_FUNC_encoder_encode_fn官方文档END openssl3.2 - note - Decoders and Encoders with OpenSSL 概述 …
阅读更多...
‍Java OCR技术全面解析：六大解决方案比较

‍Java OCR技术全面解析：六大解决方案比较

博主猫头虎的技术世界 &#x1f31f; 欢迎来到猫头虎的博客 — 探索技术的无限可能&#xff01; 专栏链接&#xff1a; &#x1f517; 精选专栏&#xff1a; 《面试题大全》 — 面试准备的宝典&#xff01;《IDEA开发秘籍》 — 提升你的IDEA技能&#xff01;《100天精通鸿蒙》 …
阅读更多...
[ C++ ] STL---stack与queue

[ C++ ] STL---stack与queue

目录 stack简介 stack的常用接口 queue简介 queue的常用接口 stack的模拟实现 queue的模拟实现 stack简介 1. stack是具有后进先出操作的一种容器适配器&#xff0c;其只能从容器的一端进行元素的插入与删除操作&#xff1b; 2. stack是作为容器适配器被实现的&#xff0…
阅读更多...
ubuntu20.04搭建rtmp视频服务

ubuntu20.04搭建rtmp视频服务

1.安装软件 sudo apt-get install ffmpeg sudo apt-get install nginx sudo apt-get install libnginx-mod-rtmp 2.nginx配置 修改/etc/nginx/nginx.conf文件&#xff0c;在末尾添加&#xff1a; rtmp {server {listen 1935;application live {live on;}} } 3.视频测试 本…
阅读更多...
使用 ZipArchiveInputStream 读取压缩包内文件总数

使用 ZipArchiveInputStream 读取压缩包内文件总数

读取压缩包内文件总数 简介 ZipArchiveInputStream 是 Apache Commons Compress 库中的一个类&#xff0c;用于读取 ZIP 格式的压缩文件。在处理 ZIP 文件时&#xff0c;编码格式是一个重要的问题&#xff0c;因为它决定了如何解释文件中的字符数据。通常情况下&#xff0c;Z…
阅读更多...
权限管理系统-0.5.0

权限管理系统-0.5.0

六、审批管理模块 审批管理模块包括审批类型和审批模板&#xff0c;审批类型如&#xff1a;出勤、人事、财务等&#xff0c;审批模板如&#xff1a;加班、请假等具体业务。 6.1 引入依赖 在项目中引入activiti7的相关依赖&#xff1a; <!--引入activiti的springboot启动器…
阅读更多...
TikTok美国本土小店如何运营？常见小白问题解答

TikTok美国本土小店如何运营？常见小白问题解答

作为资深跨境老玩家&#xff0c;虽不说是经验丰富&#xff0c;至少也是摸清了基本的玩法思路。TikTok作为近来的跨境新蓝海&#xff0c;他的玩法其实并不难&#xff0c;作为第一批试错玩家&#xff0c;今天也诚心给大家分享一些美国本土小店运营经验&#xff0c;感兴趣的话就看…
阅读更多...
当我们谈论Spring的时候到底在谈什么

当我们谈论Spring的时候到底在谈什么

题图来自APOD 你好&#xff0c;这里是codetrend专栏“Spring6全攻略”。欢迎点击关注查看往期文章。 Spring对于不做程序开发的人来说字面意思就是春天&#xff0c;四季的开始。 对于程序员来说这个单词完全拥有另外一个含义&#xff0c;Spring指的是一个开源项目&#xff0…
阅读更多...
C语言经典算法-6

C语言经典算法-6

文章目录 其他经典例题跳转链接31.数字拆解32.得分排行33.选择、插入、气泡排序34.Shell 排序法 - 改良的插入排序35.Shaker 排序法 - 改良的气泡排序 其他经典例题跳转链接 C语言经典算法-1 1.汉若塔 2. 费式数列 3. 巴斯卡三角形 4. 三色棋 5. 老鼠走迷官&#xff08;一&…
阅读更多...
Python图像处理指南：PIL与OpenCV的比较【第136篇—PIL】

Python图像处理指南：PIL与OpenCV的比较【第136篇—PIL】

&#x1f47d;发现宝藏 前些天发现了一个巨牛的人工智能学习网站&#xff0c;通俗易懂&#xff0c;风趣幽默&#xff0c;忍不住分享一下给大家。【点击进入巨牛的人工智能学习网站】。 Python图像处理指南&#xff1a;PIL与OpenCV的比较 图像处理在计算机视觉和图像识别等领域…
阅读更多...
【极简无废话】open3d可视化torch、numpy点云

【极简无废话】open3d可视化torch、numpy点云

建议直接看文档&#xff0c;很多都代码老了&#xff0c;注意把代码版本调整到你使用的open3d的版本&#xff1a; https://www.open3d.org/docs/release/tutorial/visualization/visualization.html 请注意open3d应该已经不支持centos了&#xff01; 从其他格式转换成open3d…
阅读更多...
动手做简易版俄罗斯方块

动手做简易版俄罗斯方块

导读&#xff1a;让我们了解如何处理形状的旋转、行的消除以及游戏结束条件等控制因素。 目录 准备工作 游戏设计概述 构建游戏窗口 游戏方块设计 游戏板面设计 游戏控制与逻辑 行消除和计分 判断游戏结束 界面美化和增强体验 看看游戏效果 准备工作 在开始编码之前…
阅读更多...
Memcached-分布式内存对象缓存系统

Memcached-分布式内存对象缓存系统

目录 一、NoSQL 介绍 二、Memcached 1、Memcached 介绍 1.1 Memcached 概念 1.2 Memcached 特性 1.3 Memcached 和 Redis 区别 1.4 Memcached 工作机制 1.4.1 内存分配机制 1.4.2 懒惰期 Lazy Expiration 1.4.3 LRU&#xff08;最近最少使用算法&#xff09; 1.4.4…
阅读更多...
最新文章
推荐文章

Copyright @ 2022~2023