@Override public int read(){
  if (idx >= charSequence.length()) {
    return -1;
  }
 else {
    return charSequence.charAt(idx++);
  }
}

@ Override public int read ( ) { if ( idx >= charSequence . length ( ) ) { return - 1 ; } else { return charSequence . charAt ( idx ++ ) ; } }
read a single character .
