Develop Reference

Apache POI - Java - Get Section Name - PowerPoint

Microsoft Powerpoint has a feature to split the slides by section (a logical grouping).
What's the best way to extract the section name?
Tech Stack -
Apache POI - v5.2.2
Java
I've achieved the same with VBA
sectionName = ActivePresentation.SectionProperties.Name(currentSlide.sectionIndex)

The Office Open XML which Apache POI uses is Office Open XML defined in 2006 and first published in Office 2007. This OOXML does not know something about sections in presentations. Sections were introduced later (2010).
Even ECMA-376 5th edition does not contain anything about sections in presentations. So Microsoft has not public published XSDs for this extension yet. So XmlBeans can't have created classes for it.
So if one would want using that feature, one would must manipulate the XML directly.
How to get what XML needs to be manipulated?
All Office Open XML files, so also PowerPoint *.pptx, are ZIP archives containing XML files and other files in a special directory structure. One can simply unzip a *.pptx file and have a look into.
Have a look into the /ppt/presentation.xml and you will see the XML.
What to use to manipulate the XML?
One can use org.openxmlformats.schemas.presentationml.x2006.main.* classes contained in poi-ooxml-full-5.*.jar as long as possible and else org.apache.xmlbeans.XmlObject and/or org.apache.xmlbeans.XmlCursorcontained in xmlbeans-5.*.jar. But using XmlObject directly can be very laborious.
Complete example for how to get the sections and the section names:
import java.io.FileInputStream;
import org.apache.poi.xslf.usermodel.*;
import org.apache.xmlbeans.XmlObject;
import javax.xml.namespace.QName;
public class PowerPointGetSectionProperties {
static Long getSlideId(XSLFSlide slide) {
if (slide == null) return null;
Long slideId = null;
XMLSlideShow presentation = slide.getSlideShow();
String slideRId = presentation.getRelationId(slide);
org.openxmlformats.schemas.presentationml.x2006.main.CTPresentation ctPresentation = presentation.getCTPresentation();
org.openxmlformats.schemas.presentationml.x2006.main.CTSlideIdList sldIdLst = ctPresentation.getSldIdLst();
for (org.openxmlformats.schemas.presentationml.x2006.main.CTSlideIdListEntry sldId : sldIdLst.getSldIdList()) {
if (sldId.getId2().equals(slideRId)) {
slideId = sldId.getId();
break;
}
}
return slideId;
}
static XmlObject[] getSections(org.openxmlformats.schemas.presentationml.x2006.main.CTExtensionList extList) {
if (extList == null) return new XmlObject[0];
XmlObject[] sections = extList.selectPath(
"declare namespace p14='http://schemas.microsoft.com/office/powerpoint/2010/main' "
+".//p14:section");
return sections;
}
static XmlObject[] getSectionSldIds(XmlObject section) {
if (section == null) return new XmlObject[0];
XmlObject[] sldIds = section.selectPath(
"declare namespace p14='http://schemas.microsoft.com/office/powerpoint/2010/main' "
+".//p14:sldId");
return sldIds;
}
static Long getSectionSldId(XmlObject sectionSldId) {
if (sectionSldId == null) return null;
Long sldIdL = null;
XmlObject sldIdO = sectionSldId.selectAttribute(new QName("id"));
if (sldIdO instanceof org.apache.xmlbeans.impl.values.XmlObjectBase) {
String sldIsS = ((org.apache.xmlbeans.impl.values.XmlObjectBase)sldIdO).getStringValue();
try {
sldIdL = Long.valueOf(sldIsS);
} catch (Exception ex) {
// do nothing
}
}
return sldIdL;
}
static XmlObject getSection(XSLFSlide slide) {
Long slideId = getSlideId(slide);
if (slideId != null) {
XMLSlideShow presentation = slide.getSlideShow();
org.openxmlformats.schemas.presentationml.x2006.main.CTPresentation ctPresentation = presentation.getCTPresentation();
org.openxmlformats.schemas.presentationml.x2006.main.CTExtensionList extList = ctPresentation.getExtLst();
XmlObject[] sections = getSections(extList);
for (XmlObject section : sections) {
XmlObject[] sectionSldIds = getSectionSldIds(section);
for (XmlObject sectionSldId : sectionSldIds) {
Long sldIdL = getSectionSldId(sectionSldId);
if (slideId.equals(sldIdL)) {
return section;
}
}
}
}
return null;
}
static String getSectionName(XmlObject section) {
if (section == null) return null;
String sectionName = null;
XmlObject name = section.selectAttribute(new QName("name"));
if (name instanceof org.apache.xmlbeans.impl.values.XmlObjectBase) {
sectionName = ((org.apache.xmlbeans.impl.values.XmlObjectBase)name).getStringValue();
}
return sectionName;
}
public static void main(String args[]) throws Exception {
XMLSlideShow slideShow = new XMLSlideShow(new FileInputStream("./PPTXUsingSections.pptx"));
for (XSLFSlide slide : slideShow.getSlides()) {
System.out.println(slide.getSlideName());
XmlObject section = getSection(slide);
String sectionName = getSectionName(section);
System.out.println(sectionName);
}
slideShow.close();
}
}

Adding hyperlink to inner PDF files

I have to create a PDF file by adding two PDF files inside a generated PDF file as a tree structure using iText in Java.
I have to create bookmarks with PDF file names and add a hyperlink to the bookmark. When the bookmark is clicked, the respective PDF should be opened in that PDF file itself, not as a separate PDF.
PDFTREE
pdf1
pdf2

Such bookmarks are referred to as outline elements in the PDF specification (PDF 32000-1:2008, p.367):
The outline consists of a tree-structured hierarchy of outline items (sometimes called bookmarks), which serve as a visual table of contents to display the document’s structure to the user.
If you merge the documents with PdfMerger, the outlines are copied to the resulting PDF by default. However, you want a main-node per document and not a flat list of bookmarks. Since cloning and copying outlines in no trivial task, it is best to let iText handle this. Unfortunately, we have little direct control how outlines are being merged.
We can build a SpecialMerger as a wrapper around PdfMerger to extract the cloned outlines (first step) and get them into a hierarchical structure afterwards (second step). The outline of each merged PDF is temporarily stored in the outlineList together with the desired name of the main node and its reference (page number in the merged PDF). After all the PDFs are merged, we can attach the temporarily stored outlines back to the root-node.
public static class SpecialMerger {
private final PdfDocument outputPdf;
private final PdfMerger merger;
private final PdfOutline rootOutline;
private final List<DocumentOutline> outlineList = new ArrayList<>();
private int nextPageNr = 1;
public SpecialMerger(final PdfDocument outputPdf) {
if (outputPdf.getNumberOfPages() != 0) {
throw new IllegalArgumentException("PDF must be empty");
}
this.outputPdf = outputPdf;
this.merger = new PdfMerger(outputPdf, true, true);
this.rootOutline = outputPdf.getOutlines(false);
}
public void merge(PdfDocument from, int fromPage, int toPage, String filename) {
merger.merge(from, fromPage, toPage); // merge with normal PdfMerger
// extract and clone outline of merged document
final List<PdfOutline> children = new ArrayList<>(rootOutline.getAllChildren());
rootOutline.getAllChildren().clear(); // clear root outline
outlineList.add(new DocumentOutline(filename, nextPageNr, children));
nextPageNr = outputPdf.getNumberOfPages() + 1; // update next page number
}
public void writeOutline() {
outlineList.forEach(o -> {
final PdfOutline outline = rootOutline.addOutline(o.getName()); // bookmark with PDF name
outline.addDestination(PdfExplicitDestination.createFit(outputPdf.getPage(o.getPageNr())));
outline.setStyle(PdfOutline.FLAG_BOLD);
o.getChildern().forEach(outline::addOutline); // add all extracted child bookmarks
});
}
private static class DocumentOutline {
private final String name;
private final int pageNr;
private final List<PdfOutline> childern;
public DocumentOutline(final String pdfName, final int pageNr, final List<PdfOutline> childern) {
this.name = pdfName;
this.pageNr = pageNr;
this.childern = childern;
}
public String getName() {
return name;
}
public int getPageNr() {
return pageNr;
}
public List<PdfOutline> getChildern() {
return childern;
}
}
}
Now, we can use this custom merger to merge the PDFs and then add the outline with writeOutline:
public static void main(String[] args) throws IOException {
String filename1 = "pdf1.pdf";
String filename2 = "pdf2.pdf";
try (
PdfDocument generatedPdf = new PdfDocument(new PdfWriter("output.pdf"));
PdfDocument pdfDocument1 = new PdfDocument(new PdfReader(filename1));
PdfDocument pdfDocument2 = new PdfDocument(new PdfReader(filename2))
) {
final SpecialMerger merger = new SpecialMerger(generatedPdf);
merger.merge(pdfDocument1, 1, pdfDocument1.getNumberOfPages(), filename1);
merger.merge(pdfDocument2, 1, pdfDocument2.getNumberOfPages(), filename2);
merger.writeOutline();
}
}
The result looks like this (Preview and Adobe Acrobat Reader on macOS):
Another option is to make a portfolio by embedding the PDFs. However, this is not supported by all PDF viewers and most users are not accustomed to these portfolios.
public static void main(String[] args) throws IOException {
String filename1 = "pdf1.pdf";
String filename2 = "pdf2.pdf";
try (PdfDocument generatedPdf = new PdfDocument(new PdfWriter("portfolio.pdf"))) {
Document doc = new Document(generatedPdf);
doc.add(new Paragraph("This PDF contains embedded documents."));
doc.add(new Paragraph("Use a compatible PDF viewer if you cannot see them."));
PdfCollection collection = new PdfCollection();
collection.setView(PdfCollection.TILE);
generatedPdf.getCatalog().setCollection(collection);
addAttachment(generatedPdf, filename1, filename1);
addAttachment(generatedPdf, filename2, filename2);
}
}
private static void addAttachment(PdfDocument doc, String attachmentPath, String name) throws IOException {
PdfFileSpec fileSpec = PdfFileSpec.createEmbeddedFileSpec(doc, attachmentPath, name, name, null, null);
doc.addFileAttachment(name, fileSpec);
}
The result in Adobe Acrobat Reader on macOS:

Is there a way to change Gif speed

I would like to try saving saving at a gifspeed, possibly bring up a box with speed selections, although i'm not quite sure how to change a gif speed using java.
I've looked this up but to no avail. I'm new so I'm sorry if this is a question and I just didn't find it
import base.AnimationExporter;
import java.awt.Dimension;
import java.awt.Graphics;
import settings.GuiDrawer;
public class SaveButton extends GuiElement
{
public SaveButton(GuiMenu parent)
{
super(parent);
}
public void releasedOn(int posX, int posY, int button)
{
if (heldDown) {
heldDown = false;
AnimationExporter.saveAnimation(true);
}
}
}
Edit: My bad heres AnimationExporter
try {
ImageWriter gifWriter = (ImageWriter)ImageIO.getImageWritersByFormatName("gif").next();
ImageOutputStream outputStream = ImageIO.createImageOutputStream(outputFile);
gifWriter.setOutput(outputStream);
ImageTypeSpecifier imageType = ImageTypeSpecifier.createFromBufferedImageType(2);
IIOMetadata metadata = gifWriter.getDefaultImageMetadata(imageType, null);
IIOMetadataNode nodeTree = (IIOMetadataNode)metadata.getAsTree(metadata.getNativeMetadataFormatName());
IIOMetadataNode appExtensionsNode = getNode("ApplicationExtensions", nodeTree);
IIOMetadataNode child = new IIOMetadataNode("ApplicationExtension");
child.setAttribute("applicationID", "NETSCAPE");
child.setAttribute("authenticationCode", "2.0");
child.setUserObject(new byte[] { 1, (byte)((Editing.animationLoop ? 0 : 1) & 0xFF), (byte)((Editing.animationLoop ? 0 : 1) >> 8 & 0xFF) });
appExtensionsNode.appendChild(child);
metadata.setFromTree(metadata.getNativeMetadataFormatName(), nodeTree);
gifWriter.prepareWriteSequence(null);
for (Frame frame : animation.Animation.frames) {
IIOMetadata imageMetadata = gifWriter.getDefaultImageMetadata(imageType, null);
IIOMetadataNode imageNodeTree = (IIOMetadataNode)imageMetadata.getAsTree(imageMetadata.getNativeMetadataFormatName());
IIOMetadataNode graphicNode = getNode("GraphicControlExtension", imageNodeTree);
graphicNode.setAttribute("disposalMethod", "none");
graphicNode.setAttribute("userInputFlag", "FALSE");
graphicNode.setAttribute("delayTime", Integer.toString(delay));
imageMetadata.setFromTree(imageMetadata.getNativeMetadataFormatName(), imageNodeTree);
IIOImage currentImage = new IIOImage(frame.getEntireFrame(), null, imageMetadata);
gifWriter.writeToSequence(currentImage, null);
}
gifWriter.endWriteSequence();
outputStream.close();
} catch (Exception e) {
e.printStackTrace();
}
}```

The framerate of the 'GIF' is embedded. However, you can speed it up or slow it down through external tools. Photoshop may work best. This tool may be able to help you. If you need dynamic framerate changes we need more information on the libraries you are using.

Ahh, so sorry I thought I had less copied down,l ooking at it now I feel dumb, delayTime here is,
public int delay = Editing.frameDelay;
I assume frameDelay is what I should change
public static int frameDelay = 100;

Using a pre-loaded icon

I'm using the following to show a cross in a label, that accompanies an if statement.
JLabel.setIcon(new ImageIcon(path + "Resource/cross.png"));
Instead of loading the icon everytime I would prefer to have it imported into my project and call it from there. I know how to import it but how do I modify the line of code above to point to the imported icon.

you can create a static loader methode (in an utility class) and store it there
private static Map<String, Icon> lookUpMap = new HashMap<>();
public static Icon getImageIcon(String res){
Icon icon = lookUpMap.get(res);
if(icon = null){
icon = new ImageIcon(res);
lookUpMap.put(res, icon);
}
return icon;
}
you can access the icons now everywhere
JLabel.setIcon(UtilitClass.getImageIcon(path + "Resource/cross.png));

How do you create a PDF document using iText that has pages with differing page sizes? [duplicate]

I'm using iTextSharp to generate a large document. In this document I want some specific pages in landscape. All the rest is portrait. Does anyone know how I can do this?
Starting a new document is not an option.
Thanks!

You can set the document size and it will affect the next pages. Some snippets:
Set up your document somewhere (you know that already):
var document = new Document();
PdfWriter pdfWriter = PdfWriter.GetInstance(
document, new FileStream(destinationFile, FileMode.Create)
);
pdfWriter.SetFullCompression();
pdfWriter.StrictImageSequence = true;
pdfWriter.SetLinearPageMode();
Now loop over your pages (you probably do that as well already) and decide what page size you want per page:
for (int pageIndex = 1; pageIndex <= pageCount; pageIndex++) {
// Define the page size here, _before_ you start the page.
// You can easily switch from landscape to portrait to whatever
document.SetPageSize(new Rectangle(600, 800));
if (document.IsOpen()) {
document.NewPage();
} else {
document.Open();
}
}

try this code :
using System;
using System.IO;
using iText.Kernel.Events;
using iText.Kernel.Pdf;
using iText.Layout;
using iText.Layout.Element;
namespace iText.Samples.Sandbox.Events
{
public class PageOrientations
{
public static readonly String DEST = "results/sandbox/events/page_orientations.pdf";
public static readonly PdfNumber PORTRAIT = new PdfNumber(0);
public static readonly PdfNumber LANDSCAPE = new PdfNumber(90);
public static readonly PdfNumber INVERTEDPORTRAIT = new PdfNumber(180);
public static readonly PdfNumber SEASCAPE = new PdfNumber(270);
public static void Main(String[] args)
{
FileInfo file = new FileInfo(DEST);
file.Directory.Create();
new PageOrientations().ManipulatePdf(DEST);
}
protected void ManipulatePdf(String dest)
{
PdfDocument pdfDoc = new PdfDocument(new PdfWriter(dest));
// The default page orientation is set to portrait in the custom event handler.
PageOrientationsEventHandler eventHandler = new PageOrientationsEventHandler();
pdfDoc.AddEventHandler(PdfDocumentEvent.START_PAGE, eventHandler);
Document doc = new Document(pdfDoc);
doc.Add(new Paragraph("A simple page in portrait orientation"));
eventHandler.SetOrientation(LANDSCAPE);
doc.Add(new AreaBreak());
doc.Add(new Paragraph("A simple page in landscape orientation"));
eventHandler.SetOrientation(INVERTEDPORTRAIT);
doc.Add(new AreaBreak());
doc.Add(new Paragraph("A simple page in inverted portrait orientation"));
eventHandler.SetOrientation(SEASCAPE);
doc.Add(new AreaBreak());
doc.Add(new Paragraph("A simple page in seascape orientation"));
doc.Close();
}
private class PageOrientationsEventHandler : IEventHandler
{
private PdfNumber orientation = PORTRAIT;
public void SetOrientation(PdfNumber orientation)
{
this.orientation = orientation;
}
public void HandleEvent(Event currentEvent)
{
PdfDocumentEvent docEvent = (PdfDocumentEvent) currentEvent;
docEvent.GetPage().Put(PdfName.Rotate, orientation);
}
}
}
}