外卖点餐零碎的实现
实体类的编写
(1)菜品类(菜品id，菜品名，菜品类型，上架工夫，单价，月销售，总数量)
import java.util.Date;public class Menu { private String mid; private String name; private String type; private Date dateIssued; private double price; private int monthlySales; private int totalQuantity; public Menu() { super(); // TODO Auto-generated constructor stub } public Menu(String mid, String name, String type, Date dateIssued, double price, int monthlySales, int totalQuantity) { super(); this.mid = mid; this.name = name; this.type = type; this.dateIssued = dateIssued; this.price = price; this.monthlySales = monthlySales; this.totalQuantity = totalQuantity; } public String getMid() { return mid; } public void setMid(String mid) { this.mid = mid; } 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 Date getDateIssued() { return dateIssued; } public void setDateIssued(Date dateIssued) { this.dateIssued = dateIssued; } public double getPrice() { return price; } public void setPrice(double price) { this.price = price; } public int getMonthlySales() { return monthlySales; } public void setMonthlySales(int monthlySales) { this.monthlySales = monthlySales; } public int getTotalQuantity() { return totalQuantity; } public void setTotalQuantity(int totalQuantity) { this.totalQuantity = totalQuantity; } @Override public int hashCode() { final int prime = 31; int result = 1; result = prime * result + ((dateIssued == null) ? 0 : dateIssued.hashCode()); result = prime * result + ((mid == null) ? 0 : mid.hashCode()); result = prime * result + monthlySales; result = prime * result + ((name == null) ? 0 : name.hashCode()); long temp; temp = Double.doubleToLongBits(price); result = prime * result + (int) (temp ^ (temp >>> 32)); result = prime * result + totalQuantity; result = prime * result + ((type == null) ? 0 : type.hashCode()); return result; } @Override public boolean equals(Object obj) { if (this == obj) return true; if (obj == null) return false; if (getClass() != obj.getClass()) return false; Menu other = (Menu) obj; if (dateIssued == null) { if (other.dateIssued != null) return false; } else if (!dateIssued.equals(other.dateIssued)) return false; if (mid == null) { if (other.mid != null) return false; } else if (!mid.equals(other.mid)) return false; if (monthlySales != other.monthlySales) return false; if (name == null) { if (other.name != null) return false; } else if (!name.equals(other.name)) return false; if (Double.doubleToLongBits(price) != Double.doubleToLongBits(other.price)) return false; if (totalQuantity != other.totalQuantity) return false; if (type == null) { if (other.type != null) return false; } else if (!type.equals(other.type)) return false; return true; } @Override public String toString() { return "Menu [mid=" + mid + ", name=" + name + ", type=" + type + ", dateIssued=" + dateIssued + ", price=" + price + ", monthlySales=" + monthlySales + ", totalQuantity=" + totalQuantity + "]"; }}import java.util.ArrayList;import java.util.Collection;import java.util.Date;import java.util.HashMap;import java.util.List;import java.util.Map;import java.util.Map.Entry;import java.util.Scanner;import java.util.Set;import java.util.stream.Collectors;public class MenuManager implements DAO<Menu> { static Map<String, Menu> map = new HashMap<String, Menu>(); static { map.put("01", new Menu("01", "邹蹄", "垃圾食品", new Date(2020,10,12), 200, 1200, 500)); map.put("02", new Menu("02", "邹腰子", "垃圾食品", new Date(2020,9,22), 30, 1000, 20)); map.put("03", new Menu("03", "邹大肠", "垃圾食品", new Date(2020,10,23), 88.8, 900, 1000)); map.put("04", new Menu("04", "邹肉", "垃圾食品", new Date(2020,1,1), 99.99, 10, 8829)); map.put("05", new Menu("05", "邹头", "垃圾食品", new Date(2020,7,7), 3300, 20000, 4287)); map.put("06", new Menu("06", "邹鞭", "补品", new Date(), 998, 999999, 9999)); } @Override public void insert(Menu menu) { map.put(menu.getMid(), menu); } @Override public Menu findById(String id) { return map.get(id); } //显示所有菜品(按菜品销量从高到低排序输入) @Override public List findAll() { List<Entry<String,Menu>> list = map.entrySet().stream() .sorted((p1,p2) -> p2.getValue().getMonthlySales() - p1.getValue().getMonthlySales()) .collect(Collectors.toList()); return list; } @Override public void delete(String id) { map.remove(id); } /** * 查看指定类别的菜品信息 * @param type 菜品类别 * @return */ public List<Menu> findByType(String type) { List<Menu> list = map.entrySet().stream() .filter(p -> p.getValue().getType().equals(type)) .map(p -> p.getValue()) .collect(Collectors.toList()); return list; } //依据菜品id批改菜品价格 public void replacePrice(String mid, double price) { map.replace(mid, new Menu(mid, map.get(mid).getName(), map.get(mid).getType(), map.get(mid).getDateIssued(), price, map.get(mid).getMonthlySales(), map.get(mid).getTotalQuantity())); } //依据菜品id查问菜品价格 public double showPrice(String mid) { return map.get(mid).getPrice(); } //依据菜品类别显示所有菜品 public void showType() { map.entrySet().stream() .sorted((p1,p2) -> p1.getValue().getType().compareTo(p2.getValue().getType())) .collect(Collectors.toList()) .forEach(System.out::println); } //依据菜品id批改菜品数量 public void replaceTotalQuantity(String mid, int totalQuantity) { map.replace(mid, new Menu(mid, map.get(mid).getName(), map.get(mid).getType(), map.get(mid).getDateIssued(), map.get(mid).getPrice(), map.get(mid).getMonthlySales(), map.get(mid).getTotalQuantity() - totalQuantity)); }}管理员类(管理员id，账号，明码)
public class Administrator { private String aid; private String account; private String password; public Administrator() { super(); // TODO Auto-generated constructor stub } public Administrator(String aid, String account, String password) { super(); this.aid = aid; this.account = account; this.password = password; } @Override public int hashCode() { final int prime = 31; int result = 1; result = prime * result + ((account == null) ? 0 : account.hashCode()); result = prime * result + ((aid == null) ? 0 : aid.hashCode()); result = prime * result + ((password == null) ? 0 : password.hashCode()); return result; } @Override public boolean equals(Object obj) { if (this == obj) return true; if (obj == null) return false; if (getClass() != obj.getClass()) return false; Administrator other = (Administrator) obj; if (account == null) { if (other.account != null) return false; } else if (!account.equals(other.account)) return false; if (aid == null) { if (other.aid != null) return false; } else if (!aid.equals(other.aid)) return false; if (password == null) { if (other.password != null) return false; } else if (!password.equals(other.password)) return false; return true; } @Override public String toString() { return "Administrator [aid=" + aid + ", account=" + account + ", password=" + password + "]"; } public String getAid() { return aid; } public void setAid(String aid) { this.aid = aid; } public String getAccount() { return account; } public void setAccount(String account) { this.account = account; } public String getPassword() { return password; } public void setPassword(String password) { this.password = password; }}import java.util.HashMap;import java.util.List;import java.util.Map;import java.util.stream.Collectors;public class AdministratorManager implements DAO<Administrator> { static Map<String, Administrator> map = new HashMap<String, Administrator>(); static { map.put("admin", new Administrator("admin", "admin123", "12345")); } public void insert(Administrator t) { map.put(t.getAid(), t); } @Override public Administrator findById(String id) { return map.get(id); } @Override public List<Administrator> findAll() { List<Administrator> list = map.entrySet().stream() .map(e -> e.getValue()) .collect(Collectors.toList()); return list; } @Override public void delete(String id) { map.remove(id); }}客户类(客户id，客户名，性别，明码，送餐地址，手机号，创立工夫)
import java.util.Date;public class Client { private String cid; private String name; private String sex; private String password; private String address; private String phone; private Date creationTime; public Client() { super(); // TODO Auto-generated constructor stub } public Client(String cid, String name, String sex, String password, String address, String phone, Date creationTime) { super(); this.cid = cid; this.name = name; this.sex = sex; this.password = password; this.address = address; this.phone = phone; this.creationTime = creationTime; } public String getCid() { return cid; } public void setCid(String cid) { this.cid = cid; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getSex() { return sex; } public void setSex(String sex) { this.sex = sex; } public String getPassword() { return password; } public void setPassword(String password) { this.password = password; } public String getAddress() { return address; } public void setAddress(String address) { this.address = address; } public String getPhone() { return phone; } public void setPhone(String phone) { this.phone = phone; } public Date getCreationTime() { return creationTime; } public void setCreationTime(Date creationTime) { this.creationTime = creationTime; } @Override public int hashCode() { final int prime = 31; int result = 1; result = prime * result + ((address == null) ? 0 : address.hashCode()); result = prime * result + ((cid == null) ? 0 : cid.hashCode()); result = prime * result + ((creationTime == null) ? 0 : creationTime.hashCode()); result = prime * result + ((name == null) ? 0 : name.hashCode()); result = prime * result + ((password == null) ? 0 : password.hashCode()); result = prime * result + ((phone == null) ? 0 : phone.hashCode()); result = prime * result + ((sex == null) ? 0 : sex.hashCode()); return result; } @Override public boolean equals(Object obj) { if (this == obj) return true; if (obj == null) return false; if (getClass() != obj.getClass()) return false; Client other = (Client) obj; if (address == null) { if (other.address != null) return false; } else if (!address.equals(other.address)) return false; if (cid == null) { if (other.cid != null) return false; } else if (!cid.equals(other.cid)) return false; if (creationTime == null) { if (other.creationTime != null) return false; } else if (!creationTime.equals(other.creationTime)) return false; if (name == null) { if (other.name != null) return false; } else if (!name.equals(other.name)) return false; if (password == null) { if (other.password != null) return false; } else if (!password.equals(other.password)) return false; if (phone == null) { if (other.phone != null) return false; } else if (!phone.equals(other.phone)) return false; if (sex == null) { if (other.sex != null) return false; } else if (!sex.equals(other.sex)) return false; return true; } @Override public String toString() { return "Client [cid=" + cid + ", name=" + name + ", sex=" + sex + ", password=" + password + ", address=" + address + ", phone=" + phone + ", creationTime=" + creationTime + "]"; }}import java.util.ArrayList;import java.util.Collection;import java.util.Date;import java.util.HashMap;import java.util.List;import java.util.Map;import java.util.Map.Entry;import java.util.Set;import java.util.stream.Collectors;public class ClientManager implements DAO<Client> { static Map<String, Client> map = new HashMap<String, Client>(); static { map.put("abc123", new Client("abc123", "张三", "男", "12345", "光谷金融港27栋9楼", "10086", new Date())); } @Override public void insert(Client t) { map.put(t.getCid(), t); } @Override public Client findById(String id) { return map.get(id); } @Override public List<Client> findAll() { List<Client> list = map.entrySet().stream() .map(e -> e.getValue()) .collect(Collectors.toList()); return list; } @Override public void delete(String id) { map.remove(id); } //批改明码 public void replacePassword(Client client, String password) { client.setPassword(password); map.replace(client.getCid(), client); }}订单类(订单号，订单创立工夫，菜品id，购买数，客户id，总价格，订单状态)
import java.util.Date;public class Indent { private String no; private Date creationTime; private String mid; private int buyNumber; private String cid; private double totalPrice; private int orderStatus; public Indent() { super(); // TODO Auto-generated constructor stub } public Indent(String no, Date creationTime, String mid, int buyNumber, String cid, double totalPrice, int orderStatus) { super(); this.no = no; this.creationTime = creationTime; this.mid = mid; this.buyNumber = buyNumber; this.cid = cid; this.totalPrice = totalPrice; this.orderStatus = orderStatus; } public String getNo() { return no; } public void setNo(String no) { this.no = no; } public Date getCreationTime() { return creationTime; } public void setCreationTime(Date creationTime) { this.creationTime = creationTime; } public String getMid() { return mid; } public void setMid(String mid) { this.mid = mid; } public int getBuyNumber() { return buyNumber; } public void setBuyNumber(int buyNumber) { this.buyNumber = buyNumber; } public String getCid() { return cid; } public void setCid(String cid) { this.cid = cid; } public double getTotalPrice() { return totalPrice; } public void setTotalPrice(double totalPrice) { this.totalPrice = totalPrice; } public int getOrderStatus() { return orderStatus; } public void setOrderStatus(int orderStatus) { this.orderStatus = orderStatus; } @Override public int hashCode() { final int prime = 31; int result = 1; result = prime * result + buyNumber; result = prime * result + ((cid == null) ? 0 : cid.hashCode()); result = prime * result + ((creationTime == null) ? 0 : creationTime.hashCode()); result = prime * result + ((mid == null) ? 0 : mid.hashCode()); result = prime * result + ((no == null) ? 0 : no.hashCode()); result = prime * result + orderStatus; long temp; temp = Double.doubleToLongBits(totalPrice); result = prime * result + (int) (temp ^ (temp >>> 32)); return result; } @Override public boolean equals(Object obj) { if (this == obj) return true; if (obj == null) return false; if (getClass() != obj.getClass()) return false; Indent other = (Indent) obj; if (buyNumber != other.buyNumber) return false; if (cid == null) { if (other.cid != null) return false; } else if (!cid.equals(other.cid)) return false; if (creationTime == null) { if (other.creationTime != null) return false; } else if (!creationTime.equals(other.creationTime)) return false; if (mid == null) { if (other.mid != null) return false; } else if (!mid.equals(other.mid)) return false; if (no == null) { if (other.no != null) return false; } else if (!no.equals(other.no)) return false; if (orderStatus != other.orderStatus) return false; if (Double.doubleToLongBits(totalPrice) != Double.doubleToLongBits(other.totalPrice)) return false; return true; } @Override public String toString() { return "Indent [no=" + no + ", creationTime=" + creationTime + ", mid=" + mid + ", buyNumber=" + buyNumber + ", cid=" + cid + ", totalPrice=" + totalPrice + ", orderStatus=" + orderStatus + "]"; }}import java.util.HashMap;import java.util.List;import java.util.Map;import java.util.stream.Collectors;public class IndentManager implements DAO<Indent> { static Map<String, Indent> map = new HashMap<String, Indent>(); @Override public void insert(Indent t) { map.put(t.getNo(), t); } @Override public Indent findById(String id) { return map.get(id); } @Override public List<Indent> findAll() { List<Indent> list = map.entrySet().stream() .map(e -> e.getValue()) .collect(Collectors.toList()); return list; } @Override public void delete(String no) { map.remove(no); } //依据id批改订单状态（0:未领取 1：已领取 2：配送中 3：已实现） public void replaceOrderStatus(String no, int orderStatus) { map.replace(no, new Indent(map.get(no).getNo(), map.get(no).getCreationTime(), map.get(no).getMid(), map.get(no).getBuyNumber(), map.get(no).getCid(), map.get(no).getTotalPrice(), orderStatus)); } //查看以后登录客户的所有订单 public void showIndent(String cid) { map.entrySet().stream() .filter(p -> p.getValue().getCid().equals(cid)) .collect(Collectors.toList()) .forEach(System.out::println); }}主体实现
import java.util.Date;import java.util.List;import java.util.Scanner;public class MySystem { static MenuManager menu = new MenuManager(); static ClientManager client = new ClientManager(); static IndentManager indent = new IndentManager(); public static void p(Object s) { System.out.println(s); } public static void administratorPanel() { p("\t管理员零碎面板\t"); p("\t①增加菜品\t"); p("\t②查看所有菜品信息(蕴含分页性能)\t"); p("\t③查看指定类别的菜品信息\t"); p("\t④依据菜品id批改菜品价格\t"); p("\t⑤删除指定id的菜品\t"); p("\t⑥增加客户\t"); p("\t⑦查看客户列表\t"); p("\t⑧删除指定id的客户\t"); p("\t⑨订单列表显示\t"); p("\t⑩依据订单id批改订单状态\t"); p("\t⑪退出\t"); p("请输出数字1~11，别离应用相应的性能"); Scanner sc = new Scanner(System.in); switch (sc.nextInt()) { case 1: p("请依照程序输出：菜品id/菜品名/菜品类型/上架工夫/单价/月销售/总数量"); menu.insert(new Menu(sc.next(), sc.next(), sc.next(), new Date(), sc.nextDouble(), sc.nextInt(), sc.nextInt())); administratorPanel(); break; case 2: p("请输出须要查问的页数"); int pageNow = sc.nextInt(); p("请输出须要查问的页面数据条数"); int pageSize = sc.nextInt(); List<Menu> list = menu.findAll(); list.stream() .skip((pageNow - 1) * pageSize) .limit(pageSize) .forEach(System.out::println); administratorPanel(); break; case 3: p("请输出菜品类别"); String type = sc.nextLine(); menu.findByType(type).stream() .forEach(System.out::println); administratorPanel(); break; case 4: p("请输出菜品id和批改后的菜品价格"); String mid = sc.next(); double price = sc.nextDouble(); menu.replacePrice(mid, price); administratorPanel(); break; case 5: p("请输出要删除菜品的id"); String mid2 = sc.next(); menu.delete(mid2); administratorPanel(); break; case 6: p("增加客户,请依照程序输出客户信息：客户id，客户名，性别，明码，送餐地址，手机号，创立工夫"); client.insert(new Client(sc.next(), sc.next(), sc.next(), sc.next(), sc.next(), sc.next(), new Date())); administratorPanel(); break; case 7: List<Client> clientList = client.findAll(); for (Client c : clientList) { System.out.println(c); } administratorPanel(); break; case 8: p("请输出要删除客户的id"); String cid = sc.next(); client.delete(cid); administratorPanel(); break; case 9: List<Indent> indentList = indent.findAll(); for (Indent i : indentList) { System.out.println(i); } administratorPanel(); break; case 10: p("请依据订单id批改订单状态orderStatus"); p("请输出订单id"); String no = sc.next(); p("请输出要批改的订单状态（0:未领取 1：已领取 2：配送中 3：已实现）"); int orderStatus = sc.nextInt(); indent.replaceOrderStatus(no, orderStatus); administratorPanel(); break; case 11: login(); break; default: administratorPanel(); break; } } public static void clientPanel(Client c) { p("\t用户零碎面板\t"); p("\t①显示所有菜品(按菜品销量从高到低排序输入)\t"); p("\t②依据菜品类别显示所有菜品\t"); p("\t③查看所有订单(以后登录用户的)\t"); p("\t④批改明码（以后登录用户的）\t"); p("\t⑤个人信息显示\t"); p("\t⑥退出登录\t"); p("请输出数字1~6，别离应用相应的性能"); MenuManager menu = new MenuManager(); Scanner sc = new Scanner(System.in); switch (sc.nextInt()) { case 1: //显示所有菜品(按菜品销量从高到低排序输入) menu.findAll().stream() .forEach(System.out::println); p("请输出菜品id"); String mid = sc.next(); p("请输出购买数量"); int buyNumber = sc.nextInt(); //批改菜品总数 menu.replaceTotalQuantity(mid, buyNumber); //查问菜品价格 double price = menu.showPrice(mid); indent.insert(new Indent(c.getCid()+mid, new Date(), mid, buyNumber, c.getCid(), price * buyNumber, 0)); clientPanel(c); break; case 2: menu.showType(); clientPanel(c); break; case 3: indent.showIndent(c.getCid()); clientPanel(c); break; case 4: System.out.println("请输出批改后的明码"); String password = sc.next(); client.replacePassword(c, password); clientPanel(c); break; case 5: System.out.println(c.toString()); clientPanel(c); break; case 6: login(); break; default : clientPanel(c); } } public static void login() { AdministratorManager am = new AdministratorManager(); ClientManager cm = new ClientManager(); Scanner sc = new Scanner(System.in); p("请输出id"); String id = sc.nextLine(); p("请输出明码"); String password = sc.nextLine(); if(am.map.get(id) != null && am.map.get(id).getPassword().equals(password)) { p("管理员登录胜利"); administratorPanel(); } else if(cm.map.get(id) != null && cm.map.get(id).getPassword().equals(password)) { p("客户登录胜利"); clientPanel(cm.map.get(id)); } else { p("登录失败，请从新登录"); login(); } } public static void main(String[] args) { login(); }}最初
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