J.java

import java.lang.reflect.*;

/*

./jdk1.6.0/bin/java J
hi

./jdk1.7.0/bin/java J
bye

*/
class J {
  public static void main(String[] args) {
    Method[] m = String.class.getDeclaredMethods();
    String s = m.length % 2 == 0 ? "hi" : "bye";
    System.out.println(s);
  }
}