Count.java

// Count.java -- count number of 'a's in 1st command line argument

class Count {

   public static void main (String args[]) {

      final String s = args[0];              // "s" is assigned once
      int count = 0;                         // "count" is changed
      for (int i=0; i<s.length(); i++) {
	 if (s.charAt(i) == 'a') count++;
      }
   }

}