java 制作类似DOS功能

import java.io.*;
import java.util.Calendar;  
import java.util.Date; 
public class DOS {
public static void dos() throws IOException{
System.out.println("欢迎进入DOS!");
String t="请输入您的命令";
while(true){

System.out.println(t);
String a=Scaner.scaner();
if(a.equalsIgnoreCase("exit"))
{
break;
}else if(a.equalsIgnoreCase("dir"))
{
System.out.println("请输入您要查看的目录！");
String b=Scaner.scaner();
File f=new File(b);
File []fs=f.listFiles();
for(int i=0;i<fs.length;i++)
{
if(fs[i].isDirectory())
{
System.out.println(fs[i].getAbsolutePath()+"\t"+"<DIR>"+"\t"+"该文件的大小为："+fs[i].length()+"\t"+"该文件是否为隐藏文件"+fs[i].isHidden());
}else if(fs[i].isFile())
{
System.out.println(fs[i].getAbsolutePath()+"\t"+"文件的大小"+fs[i].length()/1024.0+"KB"+"\t"+"该文件是否为隐藏文件"+fs[i].isHidden());
}
}
}else if(a.equalsIgnoreCase("help"))
{
System.out.println("dir\t显示目录");
System.out.println("exit\t退出DOS");
System.out.println("copy\t拷贝文件");
System.out.println("md\t创建目录");
System.out.println("help\t帮助");
System.out.println("date\t显示日期");
System.out.println("time\t显示时间");
System.out.println("del\t删除");
System.out.println("ver\t显示版本");
}else if(a.equalsIgnoreCase("copy"))
{
System.out.println("请输入您要拷贝的文件！");
String s=Scaner.scaner();
System.out.println("请输入你要拷贝文件到的位置！");
String e=Scaner.scaner();
BufferedInputStream x=new BufferedInputStream(new FileInputStream(s));
BufferedOutputStream y=new BufferedOutputStream(new FileOutputStream(e));
int v=0;
while((v=x.read())!=-1)
{
y.write(v);
}
x.close();
y.close();
System.out.println("文件拷贝成功！");
}else if(a.equalsIgnoreCase("md"))
{
System.out.println("请输入您要创建的目录！");
String s=Scaner.scaner();
File f=new File(s);
boolean b=f.mkdirs();
if(b){
System.out.println("目录创建成功！");
}else{
System.out.println("目录创建失败！请与管理员联系！");
}
}else if(a.equalsIgnoreCase("date"))
{
Calendar calendar=Calendar.getInstance();  //日历 获得实例
    calendar.setTime(new Date());//规定的时间   
    String year=String.valueOf(calendar.get(Calendar.YEAR));  
    String month=String.valueOf(calendar.get(Calendar.MONTH)+1);  
    String day=String.valueOf(calendar.get(Calendar.DAY_OF_MONTH));  
    System.out.println("现在时间是："+year+"年"+month+"月"+day); 
}else if(a.equalsIgnoreCase("time"))
{
Calendar calendar=Calendar.getInstance();  //日历 获得实例
    calendar.setTime(new Date());//规定的时间   
    String hour=String.valueOf(calendar.get(Calendar.HOUR));
    String minute=String.valueOf(calendar.get(Calendar.MINUTE));
    String second=String.valueOf(calendar.get(Calendar.SECOND));
    System.out.println("现在的时间是"+hour+"时"+minute+"分"+second+"秒");
}else if(a.equalsIgnoreCase("del"))
{
System.out.println("请输入您要删除的文件");
String s=Scaner.scaner();
File f=new File(s);
boolean b=f.delete();
if(b){
System.out.println("文件删除成功!");
}else{
System.out.println("文件删除失败！");
}
}else if(a.equalsIgnoreCase("ver"))
{
System.out.println("版本：1.0");
}else if(a.equalsIgnoreCase("prompt"))
{
System.out.println("请输入新的提示符！");
String s=Scaner.scaner();
t=s;
}else if(a.equalsIgnoreCase("run"))
{
System.out.println("请您输入要运行的windows命令：");
String s=Scaner.scaner();
Runtime.getRuntime().exec(s);
}
}
System.out.println("感谢您的使用！再见！");
}
public static void main(String[] args) throws IOException {
DOS.dos();
}
}