如何在Java中的iext中调整图像大小

Question

This is my source code.

  Document document = new Document();
    String txtVehNo = "";
    String fDate = "", tDate = "", remtype = "0";
    String fileName = "Reminders_" + Utility.sysDate("yyyy_MM_dd") + ".pdf";
    String asDate = Utility.sysDate("dd/MM/yyyy");
    ArrayList<ReminderPDF> reminderPDFs = null;
    UserDetails userDetails = null;
    String txtMarNo = "";
    String formattedDate = "";
    String address = "";



    Blob imageBlob = null;
    byte[] imageBytes = new byte[0];

    try {
        txtVehNo = request.getParameter("txtVehNo2");
        fDate = request.getParameter("txtDate3");
        tDate = request.getParameter("txtDate4");
        remtype = request.getParameter("remtype");
        txtMarNo = request.getParameter("txtMarNo");

        if (txtVehNo != null && txtVehNo != "") {

            reminderPDFs = DataManagerBean.downloadRemindersForRequirementLetter(txtVehNo, remtype);


        } else if (txtMarNo != null && txtMarNo != "") {

            reminderPDFs = DataManagerBean.downloadRemindersForRequirementLetterByMarNo(txtMarNo, remtype);


        } else {

            reminderPDFs = DataManagerBean.downloadRemindersForRequirementLetter(fDate, tDate, remtype);


        }
        if (reminderPDFs.size() > 0) {

            response.setContentType("application/pdf");
            response.setHeader("Content-disposition", "attachment; filename=\"" + fileName + "\"");
            PdfWriter.getInstance(document, response.getOutputStream());
            //PdfWriter.getInstance(document, new FileOutputStream(fileName));
            document.open();
            document.setPageSize(PageSize.A4);
            document.setMargins(85, 85, 85, 85);
            for (int i = 0; i < reminderPDFs.size(); i++) {
                String adrstr[] = reminderPDFs.get(i).address.split("\r\n");

                address = reminderPDFs.get(i).address.replaceAll(adrstr[adrstr.length - 1], "");
                document.newPage();
                Paragraph[] paragraph = new Paragraph[8];
                paragraph[0] = new Paragraph(new Phrase(reminderPDFs.get(i).mainHeader, FontFactory.getFont(FontFactory.COURIER, 12, Font.BOLD)));
                paragraph[0].setAlignment(Element.ALIGN_RIGHT);
                document.add(paragraph[0]);
                paragraph[1] = new Paragraph(new Phrase(reminderPDFs.get(i).subHeader, FontFactory.getFont(FontFactory.COURIER, 11)));
                paragraph[1].setAlignment(Element.ALIGN_RIGHT);
                document.add(paragraph[1]);
                if (reminderPDFs.get(i).print.equals("Y")) {
                    paragraph[2] = new Paragraph(new Phrase("(Reprint)", FontFactory.getFont(FontFactory.COURIER, 10)));
                } else {
                    paragraph[2] = new Paragraph(new Phrase("", FontFactory.getFont(FontFactory.COURIER, 11)));
                }
                paragraph[2].setAlignment(Element.ALIGN_RIGHT);
                document.add(paragraph[2]);
                paragraph[3] = new Paragraph(new Phrase("Date : " + reminderPDFs.get(i).asDate, FontFactory.getFont(FontFactory.COURIER, 11)));
                paragraph[3].setAlignment(Element.ALIGN_RIGHT);
                document.add(paragraph[3]);
                paragraph[4] = new Paragraph(new Phrase(" ", FontFactory.getFont(FontFactory.COURIER, 12, Font.BOLD)));
                paragraph[4].setAlignment(Element.ALIGN_CENTER);
                document.add(paragraph[4]);
                paragraph[5] = new Paragraph(new Phrase(address, FontFactory.getFont(FontFactory.COURIER, 11, Font.BOLD)));
                paragraph[5].setAlignment(Element.ALIGN_LEFT);
                document.add(paragraph[5]);
                paragraph[6] = new Paragraph(new Phrase("\n" + adrstr[adrstr.length - 1], FontFactory.getFont(FontFactory.COURIER, 11, Font.PLAIN)));
                paragraph[6].setAlignment(Element.ALIGN_LEFT);
                document.add(paragraph[6]);
                paragraph[7] = new Paragraph(new Phrase(" ", FontFactory.getFont(FontFactory.COURIER, 12, Font.BOLD)));
                paragraph[7].setAlignment(Element.ALIGN_CENTER);
                document.add(paragraph[7]);

                PdfPTable table = new PdfPTable(2);
                table.setWidthPercentage(100);


                formattedDate = Utility.dateFormatter(reminderPDFs.get(i).dol, "yyyy-MM-dd", "dd-MM-yyyy");

                table.addCell(new Phrase("Vehicle No: " + reminderPDFs.get(i).vehno, FontFactory.getFont(FontFactory.COURIER, 11)));
                table.addCell(new Phrase("MAR No       : " + reminderPDFs.get(i).marno, FontFactory.getFont(FontFactory.COURIER, 11)));
                table.addCell(new Phrase("Policy No : " + reminderPDFs.get(i).policyno, FontFactory.getFont(FontFactory.COURIER, 11)));
                table.addCell(new Phrase("Date of Loss : " + formattedDate, FontFactory.getFont(FontFactory.COURIER, 11)));
                document.add(table);

                Paragraph[] paragraph2 = new Paragraph[3];
                paragraph2[0] = new Paragraph(new Phrase(" ", FontFactory.getFont(FontFactory.COURIER, 12, Font.BOLD)));
                paragraph2[0].setAlignment(Element.ALIGN_CENTER);
                document.add(paragraph2[0]);

                String[] docs = reminderPDFs.get(i).content.split("\r\n");

                paragraph2[1] = new Paragraph(new Phrase(docs[0], FontFactory.getFont(FontFactory.COURIER, 11)));
                paragraph2[1].setAlignment(Element.ALIGN_JUSTIFIED);
                document.add(paragraph2[1]);
                paragraph2[2] = new Paragraph(new Phrase(" ", FontFactory.getFont(FontFactory.COURIER, 12, Font.BOLD)));
                paragraph2[2].setAlignment(Element.ALIGN_CENTER);
                document.add(paragraph2[2]);


                // if (reminderPDFs.get(i).docs.length() > 0) {
                int k = 1;
                for (int j = 1; j < docs.length; j++) {
                    if (!docs[j].trim().equalsIgnoreCase("")) {
                        document.add(new Paragraph(new Phrase("          " + k + ". " + docs[j].trim(), FontFactory.getFont(FontFactory.COURIER, 11))));
                        k++;
                    }
                }
                // }

                Paragraph[] paragraph3 = new Paragraph[7];
                paragraph3[0] = new Paragraph(new Phrase(" ", FontFactory.getFont(FontFactory.COURIER, 14, Font.BOLD)));
                paragraph3[0].setAlignment(Element.ALIGN_CENTER);
                document.add(paragraph3[0]);

                paragraph3[1] = new Paragraph(new Phrase("Thank You,", FontFactory.getFont(FontFactory.COURIER, 11)));
                paragraph3[1].setAlignment(Element.ALIGN_LEFT);
                document.add(paragraph3[1]);

                paragraph3[2] = new Paragraph(new Phrase("Yours Faithfully,", FontFactory.getFont(FontFactory.COURIER, 11)));
                paragraph3[2].setAlignment(Element.ALIGN_LEFT);
                document.add(paragraph3[2]);

                paragraph3[3] = new Paragraph(new Phrase("Union Assurance General Ltd", FontFactory.getFont(FontFactory.COURIER, 11, Font.BOLD)));
                paragraph3[3].setAlignment(Element.ALIGN_LEFT);
                document.add(paragraph3[3]);

                paragraph3[4] = new Paragraph(new Phrase(" ", FontFactory.getFont(FontFactory.COURIER, 12, Font.BOLD)));
                paragraph3[4].setAlignment(Element.ALIGN_CENTER);
                document.add(paragraph3[4]);


                imageBlob = DataManagerBean.getESignature(reminderPDFs.get(i).createdUser);
                if (imageBlob != null) {
                    imageBytes = imageBlob.getBytes(1, (int) imageBlob.length());
                    Image img = Image.getInstance(imageBytes);
                    float width = img.getWidth();
                    float hight = img.getHeight();
                    if (width > 200 || hight > 100) {
//                        img.scaleAbsoluteWidth(200);
//                        img.scaleAbsoluteHeight(100);
 //                       img.scaleAbsolute(200f, 100f);
                        img.scaleToFit(200f, 100f);
                    }
                    width = img.getScaledWidth();
                    hight = img.getScaledHeight();
                    document.add(img);
                }

                userDetails = UserBean.getUserDetailsByUserId(reminderPDFs.get(i).createdUser);

                paragraph3[5] = new Paragraph(new Phrase((userDetails.getuFName().concat(" ")).concat(userDetails.getuLName()), FontFactory.getFont(FontFactory.COURIER, 11)));
                paragraph3[5].setAlignment(Element.ALIGN_LEFT);
                document.add(paragraph3[5]);


                paragraph3[6] = new Paragraph(new Phrase(userDetails.getDesig(), FontFactory.getFont(FontFactory.COURIER, 11)));
                paragraph3[6].setAlignment(Element.ALIGN_LEFT);
                document.add(paragraph3[6]);


                //DataManagerBean.printStatusUpdate(reminderPDFs.get(i).rmid, "Y");
            }
            document.close();

            response.sendRedirect("Reminders.jsp");

        } else {
            if (txtVehNo != null && txtVehNo != "") {
                response.sendRedirect("Reminders.jsp?msgtype=3&msg=No Records for Policy/Vehicle No. - " + txtVehNo);
            } else if (txtMarNo != null && txtMarNo != "") {
                response.sendRedirect("Reminders.jsp?msgtype=4&msg=No Records for Mar No. - " + txtMarNo);
            } else if (fDate != null && fDate != "") {
                response.sendRedirect("Reminders.jsp?msgtype=5&msg=No Records between " + fDate + " to " + tDate);
            }
        }
    } catch (DocumentException e) {
        SystemMessage.getInstance().writeMessage("ERROR : DownloadRequirements.jsp - " + e.toString());
    } finally {
        try {
            //reminderPDFs = null;
        } catch (Exception ex) {
        }
    }

I tried
img.scaleAbsoluteWidth(200);
img.scaleAbsoluteHeight(100);
img.scaleAbsolute(200f, 100f);
img.scaleToFit(200f, 100f);
But non of this resizing the image.
When I debug the code I get width=200 and height= 100 for value too. I guess that means it's height and width changed.
Please let me know what is the issue in here.
THANK YOU.

Note Later
Issues wasn't any of these methods. Issue was image not compatible with that size. After I set size to 100,50 imaged resized perfectly.
Thank you again.

Answer 1

Your allegation "none of this is resizing the image" is wrong, and you are using the wrong methods to get the width and height of the image. Take a look at chapter 2 of my book :

There are different ways to change the dimensions of an image:

• The width and height parameters of scaleToFit() define the maximum dimensions of the image. If the width/height ratio differs from the aspect ratio of the image, either the width, or the height, will be smaller than the corresponding parameter of this method.
• The width and height parameters will be respected when using scaleAbsolute() . The resulting image risks being stretched in the X or Y direction if you don't choose the parameters wisely. You can also use scaleAbsoluteWidth() and scaleAbsoluteHeight() .
• scalePercent() comes in two versions: one with two parameters, a percentage for the width and a percentage for the height; and another with only one parameter, a percentage that will be applied equally to the width and the height.

It's a common misconception that resizing images in iText also changes the quality of the image. It's important to understand that iText takes the image as is: iText doesn't change the number of pixels in the image.

There are many examples that prove that these methods effectively change the size of the image in the document.

If you continue reading the documentation, you discover another problem in your code:

When creating an Image instance from a file, you won't always know its dimensions before or even after scaling it. You can get the width and height of the image with these methods:

• getWidth() and getHeight() are inherited from the Rectangle object. They return the original height and width of the image.
• getPlainWidth() and getPlainHeight() return the width and height after scaling. These are the dimensions of the image used to print it on a page.
• getScaledWidth() and getScaledHeight() return the width and height needed to print the image. These dimensions are equal to the plain width and height, except in cases where the image is rotated.

In your code, you get the original dimensions of the image. You change the dimensions of the image, and then you ask for the original dimensions. It shouldn't surprise you that you don't get different dimensions when asking for the original dimensions instead of the original dimensions.