Not able to read the exact text highlighted across

I am working on reading the highlighted from PDF document using PDBox. I was able to read the highlighted text in single line both single and multiple words. However, I could not read the highlighted text across the lines. Please find the following sample code to read the highlighted text.



PDDocument pddDocument = PDDocument.load(new File("C:\\pdf-sample.pdf"));
List allPages = pddDocument.getDocumentCatalog().getAllPages();
        for (int i = 0; i < allPages.size(); i++) {
            int pageNum = i + 1;
            PDPage page = (PDPage) allPages.get(i);
            List<PDAnnotation> la = page.getAnnotations();
            if (la.size() < 1) {
                continue;
            }
            System.out.println("Page number : "+pageNum);
            for (PDAnnotation pdfAnnot: la) {
                if (pdfAnnot.getSubtype().equals("Popup")) {
                    continue;
                }

                PDFTextStripperByArea stripper = new PDFTextStripperByArea();
                stripper.setSortByPosition(true);

                PDRectangle rect = pdfAnnot.getRectangle();
                float x = rect.getLowerLeftX() - 1;
                float y = rect.getUpperRightY() - 1;
                float width = rect.getWidth();
                float height = rect.getHeight() + rect.getHeight() / 4;

                int rotation = page.findRotation();
                if (rotation == 0) {
                    PDRectangle pageSize = page.getMediaBox();
                    y = pageSize.getHeight() - y;
                }

                Rectangle2D.Float awtRect = new Rectangle2D.Float(x, y, width, height);
                stripper.addRegion(Integer.toString(0), awtRect);
                stripper.extractRegions(page);
System.out.println("------------------------------------------------------------------");
                System.out.println("Annot type = " + pdfAnnot.getSubtype());
                 System.out.println("Getting text from region = " + stripper.getTextForRegion(Integer.toString(0)) + "\n");
                 System.out.println("Getting text from comment = " + pdfAnnot.getContents());

            }
        }

While reading the highlighted text across the lines, "pdfAnnot.getRectangle()" function returns the minimum rectangle area around the text. This gives more text than required. I could not find any API to extract the exact highlighted text.

For example: Text extracted from test PDF file.

Anyone, anywhere can open a PDF file. All you need is the free Adobe Acrobat

Reader. Recipients of other file formats sometimes can't open files because they

don't have the applications used to create the documents.

Use case 1: Reading the first bolded text, i.e PDF. No issues in reading the text highlighted in single line. The correct text will be printed as listed below:
Output: Getting text from region = "PDF"

Use case 2: Reading the second bolded text, i.e Adobe Acrobat reader, which spans in two lines. In this case, the extracted text on running the above program is:
Output: Getting text from region = "Anyone, anywhere can open a PDF file. All you need is the free Adobe Acrobat Reader. Recipients of other file formats sometimes can't open files because they".

The getRectangle() API gives the coordinates of minimum rectangle surrounded by the highlighted text. Hence, it is more text than "Adobe Acrobat Reader".

How to know the start and end points of the highlighted with in the extract region.
How to know the number of lines in the extracted region.

Any help will be highly appreciated.

I managed to extract the highlighted text by using the following code.

// PDF32000-2008
// 12.5.2 Annotation Dictionaries
// 12.5.6 Annotation Types
// 12.5.6.10 Text Markup Annotations
@SuppressWarnings({ "unchecked", "unused" })
public ArrayList<String> getHighlightedText(String filePath, int pageNumber) throws IOException {
    ArrayList<String> highlightedTexts = new ArrayList<>();
    // this is the in-memory representation of the PDF document.
    // this will load a document from a file.
    PDDocument document = PDDocument.load(filePath);
    // this represents all pages in a PDF document.
    List<PDPage> allPages =  document.getDocumentCatalog().getAllPages();
    // this represents a single page in a PDF document.
    PDPage page = allPages.get(pageNumber);
    // get  annotation dictionaries
    List<PDAnnotation> annotations = page.getAnnotations();

    for(int i=0; i<annotations.size(); i++) {
        // check subType 
        if(annotations.get(i).getSubtype().equals("Highlight")) {
            // extract highlighted text
            PDFTextStripperByArea stripperByArea = new PDFTextStripperByArea();

            COSArray quadsArray = (COSArray) annotations.get(i).getDictionary().getDictionaryObject(COSName.getPDFName("QuadPoints"));
            String str = null;

            for(int j=1, k=0; j<=(quadsArray.size()/8); j++) {

                COSFloat ULX = (COSFloat) quadsArray.get(0+k);
                COSFloat ULY = (COSFloat) quadsArray.get(1+k);
                COSFloat URX = (COSFloat) quadsArray.get(2+k);
                COSFloat URY = (COSFloat) quadsArray.get(3+k);
                COSFloat LLX = (COSFloat) quadsArray.get(4+k);
                COSFloat LLY = (COSFloat) quadsArray.get(5+k);
                COSFloat LRX = (COSFloat) quadsArray.get(6+k);
                COSFloat LRY = (COSFloat) quadsArray.get(7+k);

                k+=8;

                float ulx = ULX.floatValue() - 1;                           // upper left x.
                float uly = ULY.floatValue();                               // upper left y.
                float width = URX.floatValue() - LLX.floatValue();          // calculated by upperRightX - lowerLeftX.
                float height = URY.floatValue() - LLY.floatValue();         // calculated by upperRightY - lowerLeftY.

                PDRectangle pageSize = page.getMediaBox();
                uly = pageSize.getHeight() - uly;

                Rectangle2D.Float rectangle_2 = new Rectangle2D.Float(ulx, uly, width, height);
                stripperByArea.addRegion("highlightedRegion", rectangle_2);
                stripperByArea.extractRegions(page);
                String highlightedText = stripperByArea.getTextForRegion("highlightedRegion");

                if(j > 1) {
                    str = str.concat(highlightedText);
                } else {
                    str = highlightedText;
                }
            }
            highlightedTexts.add(str);
        }
    }
    document.close();

    return highlightedTexts;
}