datechange2.java

输入字符转换成日期,并判断日期格式是否正确

public class Datechange2{
	private int day;
	public static void main(String[] args)throws java.io.IOException{
		char b;
		StringBuffer str=new StringBuffer();
		System.out.println("请输入日期:");
		while((b=(char)System.in.read())!='\r')
		str.append(b);
		String e=str.toString();
		int c=Integer.parseInt(e);
		Datechange2 a=new Datechange2(c);
		a.output();
		}
		public Datechange2(int d){
		day=d;
	}
	public String dd(){
		String s=String.valueOf(day);
		if(s.length()==8){
		String year=s.substring(0,4);
		String month=s.substring(4,6);		
		String day=s.substring(6,8);
		int month2=Integer.parseInt(month);
		int day2=Integer.parseInt(day);
		if((month2<1||month2>12)||(day2<1||day2>31))
		return "1900/01/01";
		else return year+"/"+month+"/"+day;
	}
	else return "1900/01/01";
}
	public void output(){
	System.out.println("Date:"+dd());
}
}