public static String getModifierString(ExtractMethodInfoHelper helper) {
   String visibility = helper.getVisibility();
   LOG.assertTrue(visibility != null && visibility.length() > 0);
   final StringBuilder builder = new StringBuilder();
   builder.append(visibility);
   builder.append(" ");
   if (helper.isStatic()) {
     builder.append("static ");
   }
   return builder.toString();
 }