Java String with only ASCII characters

//package com.demo2s;

public class Main {
    public static void main(String[] argv) throws Exception {
        String s = "";
        System.out.println(allAscii(s));
    }// www  . j a v  a2  s  . c  o  m

    /**
     * Determines if a string contains only ascii characters
     */
    public static boolean allAscii(String s) {
        int len = s.length();
        for (int i = 0; i < len; ++i) {
            if ((s.charAt(i) & 0xff80) != 0) {
                return false;
            }
        }
        return true;
    }
}

//package com.demo2s;

public class Main {
    public static void main(String[] argv) throws Exception {
        String s = "demo2s.com";
        System.out.println(allAscii(s));
    }//from www.j  av  a 2s. c o m

    /**
     * Determines if a string contains only ascii characters
     */
    public static boolean allAscii(String s) {
        int len = s.length();
        for (int i = 0; i < len; ++i) {
            if ((s.charAt(i) & 0xff80) != 0) {
                return false;
            }
        }
        return true;
    }
}