Get text occurrences contained in a specified area with iTextSharp

System.util.RectangleJ rect = new System.util.RectangleJ(70, 80, 420, 500);
RenderFilter[] filter = {new RegionTextRenderFilter(rect)};
ITextExtractionStrategy strategy = new FilteredTextRenderListener(
        new LocationTextExtractionStrategy(), filter);
text = PdfTextExtractor.GetTextFromPage(reader, 1, strategy);