Java实现购物管理系统

package Endless;import java.util.ArrayList;import java.util.Random;/*** @JAVA01.person1.java* @author 当前用户：Endless作者 :Endless* @version 创建时间：2017年7月26日 下午6:29:16* //实现商品及会员信息管理(添加，删除，显示)* //实现超市结算*/import java.util.Scanner;import java.util.prefs.BackingStoreException;import java.util.prefs.Preferences;public class persion { static int s; static boolean huiyuan,xhuiyuan; static String bke="百事可乐",ke="500ml可乐一瓶",m="5公斤面粉",ss="1个苏泊尔炒菜锅",o="欧莱雅爽肤水一瓶"; static ArrayList<String>array=new ArrayList<String>(); static Preferences goodsnodes = Preferences.systemRoot().node("goods"); //创建节点 static Preferences goodschildnode = goodsnodes.node( "goods");  //创建子节点  public static void main(String []args) {  outline();  System.out.println("/t欢迎使用购物管理系统");  System.out.println("/t1.登陆系统/n/t2.退出程序/n ");  outline();  int n =scanint();   if(n == 1){    login();    }else if( n== 2){   System.out.println("已退出");  System.exit(0);  }else {  System.out.println("请重新选择：");  main(null); } } public static void outline(){  System.out.println("* * * * * * * * * * * * * * * * * * * * * * */n"); } public static int scanint(){ int x = 0; try {  Scanner scan =new Scanner(System.in);  x = scan.nextInt(); } catch (Exception e) {  System.out.println("输入有误,请输入数字："); } return x;  } public static String scanStr(){ String x = null; try {  Scanner scan =new Scanner(System.in);  x = scan.next(); } catch (Exception e) {  System.out.println("输入有误,请输入字符串："); } return x;  } public static void login(){  System.out.println(" * * * * * * * * * 登陆 * * * * * * * * * * * */n请输入密码/n：");  int n1 =scanint();  if(n1==(123123)){  System.out.println("登陆成功/n");  showMain();  }else{   System.out.println("密码错误");  System.out.println("请重新输入密码/n：");  login();  }  } private static void showMain() { System.out.println("/n/n/t欢迎使用购物管理系统/n");  outline();  System.out.println("/t/t 1. 会 员 信 息 管 理/n");  System.out.println("/t/t 2. 货 物 信 息 管 理/n");  System.out.println("/t/t 3. 购 物 结 算/n");  System.out.println("/t/t 4. 注 销/n");  outline();  System.out.print("请选择,输入数字:");  int n2 =scanint(); switch (n2) { case 1:  new user();  break; case 2:  goods();  break; case 3:  jiesuan();  break; case 4:  System.out.println("注销成功");  main(null); default:  System.out.println("没有您要的选项请重新输入");  showMain();  break; } } private static void goods() { //商品管理 ：添加商品： 编号 品名 价格 // 删除：选择标号删除 outline(); System.out.println("/t/t商品信息管理/n"); System.out.println("/t/t1,显示商品/n"); System.out.println("/t/t2,添加物品/n"); System.out.println("/t/t3,删除商品/n"); System.out.println("/t/t4,返回上级/n"); outline(); int n = scanint(); if (n==1){  showgoods(); }else if(n==2){  addgoods(); }else if(n ==3){  delgoods(); }else if(n==4) {  showMain(); }else {  goods(); } } private static void delgoods() {   System.out.println("请选择要删除商品的ID：/n按0返回上级");   try {   Scanner scan =new Scanner(System.in);   int x = scan.nextInt();   boolean remove=false;   for (int i=0;i<array.size();i++){    if(x==Integer.parseInt(array.get(i))){    remove=true;    }   }   if (remove){    goodschildnode.remove(Integer.toString(x));    System.out.println("删除成功");    goods();   }else if (x==0) {    goods();   }else {   System.out.println("没有此商品！");     delgoods();   }   new user();   } catch (Exception e) {   System.out.println("请输入数字");    delgoods();   } } private static void showgoods() {  try {   int leng =goodschildnode.keys().length;   syncread();   if(leng==0){   System.out.println("没有商品");   }else{   try {    System.out.println("当前有"+goodschildnode.keys().length+"种商品");    for(int i = 0;i<=goodschildnode.keys().length;i++){    String shows =goodschildnode.get(array.get(i), "");     System.out.println(shows);     System.out.println("──────────────────────────────────────────────");     }    System.out.println("00000000");    } catch (Exception e) {    }   }  } catch (BackingStoreException e) {  }  System.out.println("111111111");   goods();  } private static void syncread() {  try {  String[] arr= goodschildnode.keys();  goodschildnode.sync();  array.clear();  for(int i=0;i<arr.length;i++){  array.add(arr[i]);  }  } catch (Exception e) {  } } private static int check(int x) {  Random n=new Random();  syncread();  for(int i=0;i<array.size();i++){   if(x==Integer.parseInt(array.get(i))){   check(n.nextInt(999)+1);   }   }   return x; } private static void addgoods(){  outline();  System.out.println("/t/t请输入商品信息");  System.out.println("/t/t品名,价格(元),单位");  System.out.println("/t/t回车换行区分");  outline();  syncread();  String name =scanStr();  String nuit =scanStr();  int price = scanint();   Random n=new Random();  String id ;   id=Integer.toString(check(n.nextInt(999)+1));   try{   goodschildnode.put(id, "ID:"+id+" 品名："+name+" 价格："+price+" 单位："+nuit);   syncread();   System.out.println("第"+(goodschildnode.keys().length)+"种商品添加成功");   System.out.println("当前商品"+goodschildnode.keys().length+"种/n"+array+"/n"+array.size());   goods();   } catch (Exception e) {   goods();   } } static void jiesuan(){ try{  System.out.println("是否会员？是选1 否选0");  int x= scanint();  if (x==1){   huiyuan = true;   Scanner sc =new Scanner(System.in);    System.out.println("请输入您的会员号：");   int hui = sc.nextInt()/100%10;   if(hui==9){   System.out.println("恭喜你属于幸运会员,可以享受全场八折优惠");   xhuiyuan = true;   }else{   xhuiyuan = false;   }  }else if (x==0) {   huiyuan = false;  }  System.out.println("请输入消费金额:");  Scanner scan =new Scanner(System.in);   if(scan.hasNext()){  s=scan.nextInt();  outline();  System.out.println("是否参加优惠换购活动：" );  System.out.println("1:满50元，加2元换购"+bke );  System.out.println("2:满100元，加3元换购" +ke);  System.out.println("3:满100元，加10元换购" +m );  System.out.println("4:满200元，加10元换购" +ss );  System.out.println("5:满200元，加20元换购 " +o );  System.out.println("0：不换购/n请选择：/n" );  outline();  os();  }  } catch (Exception e) {  System.out.println("请输入数字");  jiesuan(); } }  static void out(String n , double s){ if(!(n==null)){  System.out.println("成功换购"+n); } System.out.println("本次消费总金额："+s+"元"); if (huiyuan && xhuiyuan){  System.out.println("尊敬的幸运会员，本次消费享受8折优惠");  double x =s*0.8;  System.out.println("折扣为您节省："+(s-x)+"元"); }else if (huiyuan) {  System.out.println("尊敬的会员，本次消费享受9折优惠");  double x =s*0.9;  System.out.println("折扣为您节省："+(s-x)+"元"); } System.out.println("实际消费总金额："+s+"元"); showMain(); } static void os(){  switch (scanint()) {  case 0:  out(null,s);  case 1:  if(s>=52){   out(bke,s+2);  }else{   Err();  }  case 2:  if(s>=103){   out(ke,s+3);  }else{   Err();  }  break;  case 3:  if(s>=110){   out(m,s+10);  }else{   Err();  }  break;  case 4:  if(s>=210){   out(ss,s+10);  }else{   Err();  }  break;  case 5:  if(s>=220){   out(o,s+20);  }else{   Err();  }  break;  default:  System.out.println("请重新选择");  os();  } } static void Err(){  System.out.println("金额不足/n");  main(null); }  static class user{  static ArrayList<String>array=new ArrayList<>();  static Preferences nodes = Preferences.systemRoot().node("user"); //创建节点  static Preferences childnode = nodes.node( "user");  //创建子节点   public user() {  outline();  System.out.println("/t/t1,添加用户");  System.out.println("/t/t2,删除用户");  System.out.println("/t/t3,显示用户");  System.out.println("/t/t4,返回上级");  outline();  try {   int x=scanint();   switch (x) {   case 1:   add();   break;   case 2:   deluser();   break;   case 3:   show();   break;   case 4:   showMain();   break;   default:   System.out.println("没有您要的选项！请重新选择");    new user();   break;   }  } catch (Exception e) {  new user();  }  } private void deluser() throws BackingStoreException {   System.out.println("请选择要删除用户的ID：/n按0返回上级");   try {   Scanner scan =new Scanner(System.in);   int x = scan.nextInt();   boolean remove=false;   for (int i=0;i<array.size();i++){    if(x==Integer.parseInt(array.get(i))){    remove=true;    }   }   if (remove){    childnode.remove(Integer.toString(x));    System.out.println("删除成功");   }else if (x==0) {   new user();   }else {   System.out.println("没有此用户！");     deluser();   }   new user();   } catch (Exception e) {   System.out.println("请输入数字");    deluser();   } } private static void show() {  try {   int leng =childnode.keys().length;   syncread();   if(leng==0){   System.out.println("没有用户");   }else{   System.out.println("当前有"+childnode.keys().length+"位用户");   for(int i = 0;i<=childnode.keys().length;i++){    String shows =childnode.get(childnode.keys()[i], "");    System.out.println(shows);    System.out.println("──────────────────────────────────────────────");    }   }  } catch (BackingStoreException e) {  }  new user();   } private static void syncread() {  try {  String[] arr= childnode.keys();  childnode.sync();  array.clear();  for(int i=0;i<arr.length;i++){  array.add(arr[i]);  }  } catch (Exception e) {  } } private static void add(){  Preferences nodes = Preferences.systemRoot().node("user"); //创建节点  Preferences childnode = nodes.node( "user");  //创建子节点   outline();  System.out.println("/t/t请输入用户信息");  System.out.println("/t/t姓名,6位卡号,年龄,电话");  System.out.println("/t/t回车换行区分");  outline();  syncread();  String name =scanStr();  int card = scanint();  int age =scanint();  String tel =scanStr();  Random n=new Random();  String id ;   id = Integer.toString(n.nextInt(999)+1);   try{   childnode.put(id, "ID:"+id+" 姓名："+name+" 卡号："+card+" 年龄："+age+" 电话："+tel);   syncread();   System.out.println("第"+(childnode.keys().length)+"位会员添加成功");   System.out.println("当前用户"+childnode.keys().length+"位/n"+array+"/n"+array.size());   new user();   } catch (Exception e) {   new user();   } } } }