迷你DVD管理器项目

 package chapter5;
 import java.util.*;

 public class MiniDVD {
     public static void main(String[] args){
         //扫描器
         Scanner input = new Scanner(System.in);
         //重要参数及初始化
         //Create four arrays with length of 7
         //定义四个数组长度为7
         int date[] = new int[7];            //borrow date
         int count[] = new int[7];            //total count
         String name[] =new String[7];        //name of DVDs
         String state[] = new String[7];        //state
         //Initiate three DVD
         //FirstDVD
         name[0] = "罗马假日";
         state[0] = "已借出";
         date[0] = 1;
         count[0] =15;
         //Second DVD
         name[1] = "风声鹤唳";
         state[1] = "可借";
         date[1] = 0;
         count[1] =12;
         //Third DVD
         name[2] = "浪漫满屋";
         state[2] = "可借";
         date[2] = 0;
         count[2] =30;

         //循环进入条件
         String choice = " ";
         boolean flag = true;
         do{
             //Create DVD Menu
             System.out.println("欢迎使用迷你DVD管理器");
             System.out.println("------------------------------------------------------");
             System.out.println("1.新增DVD");
             System.out.println("2.查看DVD");
             System.out.println("3.删除DVD");
             System.out.println("4.借出DVD");
             System.out.println("5.归还DVD");
             System.out.println("6.退出DVD");
             System.out.println("------------------------------------------------------");
             System.out.print("请选择：");
             choice = input.next();

             //Switch choice menu
             switch (choice){
                 case "1":
                     System.out.println("--->新增DVD");
                     System.out.print("\n请输入DVD名称：");
                     boolean firstMonitor = true;
                     boolean secondMonitor = false;
                     String bookName = " ";
                     do{
                         bookName= input.next();
                         if(firstMonitor){
                             for(int i = 0; i<name.length; i++){
                                 if(bookName.equals(name[i])){
                                     System.out.println("货架上已经存在该DVD，请返回目录重新选择！");
                                     secondMonitor = true;
                                     break;
                                 }
                             }
                         }
                         firstMonitor =false;
                     }while(firstMonitor);

                     if(!secondMonitor){
                         for (int j = 0;j<name.length; j++){
                             if((name[j])==null){
                                 name[j]= bookName;
                                 state[j] = "可借";
                                 count[j] = 0;
                                 System.out.println("新增《"+bookName+"》成功！");
                                 System.out.println("***************************");
                                 break;
                             }
                             if(name[name.length-2] !=null){
                                 System.out.println("DVD货架已满，添加失败！");
                                 System.out.println("***************************");
                                 break;
                             }
                         }
                     }
                     break;
                 case "2":
                     System.out.println("--->查看DVD");
                     System.out.println("序号\t状态\t名称\t\t借出日期\t借出次数");
                     for (int i = 0; i<name.length; i++){
                         if(name[i] == null){
                             System.out.println("***************************");
                             break;
                         }
                         String myDate = " ";
                         if(date[i] != 0){
                             myDate = date[i]+"日";
                         }
                         System.out.println((i+1)+"\t"+state[i]+"\t"+"《"+name[i]+"》"+"\t"+myDate+"\t"+count[i]+"次");
                     }
                     break;
                 case "3":
                     System.out.println("--->删除DVD");
                     System.out.print("\n请输入DVD名称：");
                     String delName = input.next();
                     //define index monitor: check
                     int check = -1;
                     for(int i = 0; i < name.length; i++){
                         if(delName.equals(name[i])){
                             check = i;
                             break;
                         }
                     }
                     if(check != -1){
                         if(state[check].equals("可借")){
                             //Delete operation
                             for(int j = check; j < name.length-1; j++){
                                 name[j] = name[j+1];
                                 state[j] = state[j+1];
                                 date[j] = date[j+1];
                                 count[j] = count[j+1];
                             }
                             System.out.println("删除《"+delName+"》成功！");
                             System.out.println("***************************");
                             break;
                         }else{
                             System.out.println("DVD为借出状态，不允许删除！");
                             System.out.println("***************************");
                         }
                     }else{
                         System.out.println("没有找到匹配信息！");
                         System.out.println("***************************");
                     }
                     break;
                 case "4":
                     System.out.println("--->借出DVD");
                     System.out.print("\n请输入DVD名称：");
                     String lendName = input.next();
                     //Initiate lendDate with 1, so as to enter the do-loop
                     int lendDate = 1;
                     System.out.print("请输入借出日期：");
                     //Avoid user input wrong date
                     do{
                         lendDate = input.nextInt();
                         if((lendDate<1)||(lendDate>31)){
                             System.out.print("必须输入大于等于1且小于等于31的数字，请重新输入：");
                         }
                     }while((lendDate<1)||(lendDate>31));

                     //define index monitor
                     int index = -1;
                     for(int i = 0; i < name.length; i++){
                         if(lendName.equals(name[i])){
                             index = i;
                             break;
                         }

                     }
                     //lend operation
                     if(index != -1){
                         if(state[index].equals("可借")){
                             state[index] = "已借出";
                             count[index] +=1;
                             date[index] = lendDate;
                             System.out.println("借出《"+lendName+"》成功！");
                             System.out.println("***************************");
                         }else{
                             System.out.println("《"+lendName+"》已被借出！");
                             System.out.println("***************************");
                         }
                     }else{
                         System.out.println("没有找到匹配信息！");
                         System.out.println("***************************");
                     }
                     break;
                 case "5":
                     System.out.println("--->归还DVD");
                     System.out.print("\n请输入DVD名称：");
                     String returnName = input.next();
                     //define index monitor
                     int monitor = -1;
                     for(int i = 0; i < name.length; i++){
                         if(returnName.equals(name[i])){
                             monitor = i;
                             break;
                         }

                     }
                     //Initiate myLendPeriod with 0, and enter the do-loop
                     int returnDate = 0;
                     int myLendPeriod = 0;
                     do{
                         System.out.print("请输入归还日期：");
                         //Avoid user input wrong date
                         do{
                             returnDate = input.nextInt();
                             if(monitor != -1){
                                 myLendPeriod = returnDate - date[monitor];
                             }
                             if(returnDate > 31){
                                 System.out.print("一个月只有31天，请重新输入：");
                             }
                             if(myLendPeriod < 0){
                                 System.out.println("归还日期不能小于借出日期，请重新输入：");
                             }
                         }while((returnDate>31)||(myLendPeriod<0));
                         //Return operation
                         if(monitor != -1){
                             if(state[monitor].equals("已借出")){
                                 state[monitor] = "可借";
                                 date[monitor] = 0;
                                 System.out.println("归还《"+returnName+"》成功！");
                                 System.out.println("借出日期为："+date[monitor]+"日");
                                 System.out.println("归还日期为："+returnDate+"日");
                                 System.out.println("应付租金（元）："+myLendPeriod);
                                 System.out.println("***************************");
                             }else{
                                 System.out.println("该DVD没有被借出！无法进行归还操作。");
                                 System.out.println("***************************");
                             }
                         }else{
                             System.out.println("没有找到匹配信息！");
                             System.out.println("***************************");
                         }
                         break;
                     }while(myLendPeriod < 0);
                     break;
                 case "6":
                     flag = false;
                     break;
                 default:
             }
             if(flag){
                 System.out.print("输入任意值返回:");
                 choice = input.next();
             }
         }while(flag);

         //program exit
         System.out.println("程序结束");
     }
 }