judge.java

这是一个关于判断问题的JAVA源代码

import java.io.*;
public class judge {
	public static void main(String args[]) throws IOException{
		String s;
		final String p = new String("bye");
		InputStreamReader ir;
		BufferedReader in;
		ir = new InputStreamReader(System.in);
		in = new BufferedReader(ir);
		do{ 
	        System.out.println();
	        System.out.print("please input one year,press 'bye' to quit(1000~9999):");
	        s = in.readLine();
	        if (s.equals(p))
	        break;
	        else{
		System.out.println();
		System.out.println("the year is:" + s);
		int i = Integer.parseInt(s);
		if ((i % 4) == 0 && (i % 100) != 0 || (i % 400 == 0))   /*  判断闰年  */
		   System.out.println("the year " + i + " is leap ");
		else
		   System.out.println("the year " + i + " is not leap");
		   System.out.println();    
	       } 
        }       while (s.length() == 4 );   /*  对非法数据判断并警告  */
                if (s.length() != 4 && ! s.equals(p) ) 
                System.out.println("WARN:it must be from 1000 to 9999 OR you have entered a invalid data,please check out");
     }		
}