DVD管理器

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Scanner;
import java.util.Date;

public class DVDMgr {
	DVDSet a=new DVDSet();

	Scanner input=new Scanner(System.in);
	public void initial(){
		a.name[0]="罗马假日";
		a.state[0]=0;
		a.count[0]=1;
		a.date[0]="2013-7-1";
		a.name[1]="风声鹤唳";
		a.state[1]=1;
		a.name[2]="浪漫满屋";
		a.state[2]=2;
	}
	public  void startMenu (){
		System.out.println("欢迎使用迷你DVD管理器");
		System.out.println("-----------------");
		System.out.println("0.借出排行");
		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.借出排行");
		System.out.println("7.退       出");
		System.out.println("------------------");
		System.out.println("请选择:");
		int choice=input.nextInt();
		switch(choice){
		case 1:
			System.out.println("此处实现新增DVD");
			add();
			System.out.println("*********************");
			returnMain();
			break;
		case 2:
			System.out.println("此处实现查看DVD");
			search();
			System.out.println("*********************");
			returnMain();
			break;
		case 3:
			System.out.println("此处实现删除DVD");
			delete();
			System.out.println("**********************");
			returnMain();
			break;
		case 4:
			System.out.println("此处实现借出DVD");
			lend();
			System.out.println("**********************");
			returnMain();
			break;
		case 5:
			System.out.println("此处实现归还DVD");
			returnDVD();
			System.out.println("**********************");
			returnMain();
			break;
		case 6:
			System.out.println("此处实现借出排行");
			list();
			System.out.println("**************************");
			returnMain();
			break;
		case 7:
			System.out.println("谢谢使用!");
			System.out.println("*************************");	
		}	
	}
	
	
	public void returnMain(){
		Scanner input=new Scanner(System.in);
		System.out.println("输入0返回:");
		if(input.nextInt()==0){
			startMenu();
		}else{
			System.out.println("输入错误,异常终止!");
		}
}
	 public void add(){
		 System.out.println("新增DVD");
		 System.out.println("请输入DVD的名字:");
		 String name=input.next();
		 for(int i=0;i<a.name.length;i++){
			 if(a.name[i]==null){
				 a.name[i]=name;
				 a.state[i]=1;
				 System.out.println("新增"+name+"成功!");
				 break;
			 }
		 }
		 System.out.println("**************************");
		 returnMain();
	 }
	 public void search(){
		 System.out.println("查看DVD");
		 System.out.println("序号\t状态\t名称\t借出日期:");
		 for(int i=0;i<a.name.length+1;i++){
			 if(a.name[i]==null){
				 break;
			 }else{
				 if(a.state[i]==0){
					 System.out.println((i+1)+"\t 已经借出\t"+a.name[i]+"\t"+a.date[i]);
			 }else{
				 System.out.println((i+1)+"\t可借\t"+a.name[i]+"\t"+a.date[i]);
			 }
		 }
	 }
		 System.out.println("************************");
		 returnMain();
		
}
	 public void delete(){

                 boolean con=false;
		 System.out.println("删除DVD");
		 System.out.println("请输入DVD名字:");
		 String name=input.next();
		 for(int i=0;i<a.name.length;i++){
			 if(a.name!=null&&a.name[i].equals(name)&&a.state[i]==1){
				 int j=i;
				 while(a.name[j+1]!=null){
					 a.name[j]=a.name[j+1];
					 a.state[j]=a.state[j+1];
					 a.date[j]=a.date[j+1];
					 j++;
				 }
				 a.name[j]=null;
				 a.date[j]=null;
				 
				 System.out.println("删除《"+name+"》成功!");

                                 con=true;
			 }if(a.name[i]!=null&&a.name[i].equals(name)&&a.state[i]==0){
				 System.out.println("《"+name+"》"+"已经借出,不可以删除!");

                                 con=false;
				 break;
			 }if(con=false){
				 System.out.println("没有该DVD的信息!");

                                 break;
			 }
		 }
	 }
	 public void lend(){
		 System.out.println("借出DVD");
		 System.out.println("请输入要借出DVD的名字:");
		 String want=input.next();
		 for(int i=0;i<a.name.length;i++){
			 if(a.name[i].equals(want)&&a.state[i]==1){
				 a.state[i]=0;
				 System.out.println("请输入借出日期(格式为:年-月-日):");
				 a.date[i]=input.next();
				 System.out.println("借出成功!");
				 a.count[i]++;
				 break;
			 }if(a.name.equals(want)&&a.state[i]==0){
				 System.out.println("该DVD已经被借出.");
				 break;
			 }
		 }
		 System.out.println("*********************");
		 returnMain();
				 
	 }
	 public void returnDVD(){
		 long yongjin=0;
		 System.out.println("请输入DVD的名字:");
		 String name=input.next();
		 for(int i=0;i<a.name.length;i++){
			 if(a.name[i].equals(name)&&a.state[i]==0){
				 a.state[i]=1;
				 System.out.println("请输入归还日期(格式为:年-月-日):");
				 String redate=input.next();
				 yongjin=charge(a.date[i],redate);
				 System.out.println("归还成功!");
				 System.out.println("借出日期"+a.date);
				 System.out.println("归还日期"+redate);
				 System.out.println("应付租金:"+yongjin+"元");
				  a.count[i]++;
				 break;
			 }if(a.name[i].equals(name)&&a.state[i]==1){
				 System.out.println("该DVD未被借出,无法继续操作!");
				 break;
			 }else{
				 System.out.println("未找到该DVD的信息!");
			 }
		 }
		 System.out.println("******************************");
		 returnMain();
	 }
	 public long charge(String date1,String date2){
		 long charge=0;
		 SimpleDateFormat sd=new SimpleDateFormat("yyyy-MM-dd");
		 try{
			 Date d1=sd.parse(date1);
			 Date d2=sd.parse(date2);
			 charge=(d2.getTime()-d1.getTime())/(24*60*60*1000);
			 
		 }catch(ParseException e){
			 e.printStackTrace();
		 }
		 return charge;
	 }
	 public void list(){
		 String[]newname=new String[50];
		 int[]newcount=new int[50];
		 for(int i=0;i<a.name.length;i++){
			 newname[i]=a.name[i];
			 newcount[i]=a.count[i];
			 
		 }
		 for(int i=0;i<newname.length-1;i++){
			 for(int j=0;j<newname.length-1-i;j++){
				 if(newcount[i]>newcount[j]){
					 int temp=newcount[i];
					 newcount[i]=newcount[j];
					 newcount[j]=temp;
					 String tempname=newname[i];
					 newname[i]=newname[j];
					 newname[j]=tempname;
				 }
			 }
		 }
		 System.out.println("排行榜:");
		 System.out.println("*************************");
		 System.out.println("次数\t名称");
		 for(int i=0;i<newname.length;i++){
			 if(newname[i]!=null){
				 System.out.println(newcount[i]+"\t《"+newname[i]+"》");
			 }
		 }
		 System.out.println("**********************");
		 returnMain();
	 }
	 
	 }

public class DVDSet {
	String[] name=new String[50];
	int[]state=new int[50];
	String[]date=new String[50];
	int count[]=new int[100];

}

public class Test {
	public static void main(String[] args) {
		DVDMgr dvd=new DVDMgr();
		dvd.initial();
		dvd.startMenu();
	}

}