public AbstractTreePrinter removeLastChar(){
  if (out.length() == 0) {
    return this;
  }
  if (out.charAt(out.length() - 1) == '\n') {
    currentLine--;
    currentColumn=0;
  }
 else {
    currentColumn--;
  }
  out.deleteCharAt(out.length() - 1);
  return this;
}

public AbstractTreePrinter removeLastChar ( ) { if ( out . length ( ) == 0 ) { return this ; } if ( out . charAt ( out . length ( ) - 1 ) == '\n' ) { currentLine -- ; currentColumn = 0 ; } else { currentColumn -- ; } out . deleteCharAt ( out . length ( ) - 1 ) ; return this ; }
removes the last output character .
