code: public static float getWidth(Phrase phrase, int runDirection, int arabicOptions) {
          ColumnText ct = new ColumnText(null);
          ct.addText(phrase);
          ct.addWaitingPhrase();
          PdfLine line = ct.bidiLine.processLine(0, 20000, Element.ALIGN_LEFT, runDirection, arabicOptions);
          if (line == null)
              return 0;
          else
              return 20000 - line.widthLeft();
      }
docs: Gets the width that the line will occupy after writing.
  Only the width of the first line is returned.
  
  @param phrase the <CODE>Phrase</CODE> containing the line
  @param runDirection the run direction
  @param arabicOptions the options for the arabic shaping
  @return the width of the line