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javapowerpointdocx4j

How to get name of slideLayout in pptx4j?

I use pptx4j to load an existing presentation and I need the names of each layout. With the following code, it should work in my opinion:

    // loading layout
    SlideLayoutPart layoutPart = null;
    try {
        PartName partName = new PartName("/ppt/slideLayouts/slideLayout1.xml");
        layoutPart = (SlideLayoutPart) presentationMLPackage.getParts().getParts().get(partName);
        // get name
        String layoutName = layoutPart.getContents().getCSld().getName();
        log.debug("LayoutName: " + layoutName);
    } catch (InvalidFormatException e) {
        log.error("Error - Could not load layout: " + e);
    } catch (Docx4JException e) {
        log.error("Error - Could not get layoutName: " + e);
    }

But I get a NullPointerException for layoutPart.getJaxbElement(). Is this the wrong way or why am I getting this error?

The whole exception:

java.lang.IllegalArgumentException: Unknown type of result: class javax.xml.transform.dom.DOMResult 
        at net.sf.saxon.event.SerializerFactory.getReceiver(SerializerFactory.java:154)
        at net.sf.saxon.IdentityTransformerHandler.startDocument(IdentityTransformerHandler.java:94)
        at com.sun.xml.internal.bind.v2.runtime.unmarshaller.DomLoader$State.<init>(DomLoader.java:67)
        at com.sun.xml.internal.bind.v2.runtime.unmarshaller.DomLoader.startElement(DomLoader.java:102)
        at com.sun.xml.internal.bind.v2.runtime.unmarshaller.ProxyLoader.startElement(ProxyLoader.java:45)
        at com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallingContext._startElement(UnmarshallingContext.java:486)
        at com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallingContext.startElement(UnmarshallingContext.java:465)
        at com.sun.xml.internal.bind.v2.runtime.unmarshaller.InterningXmlVisitor.startElement(InterningXmlVisitor.java:60)
        at com.sun.xml.internal.bind.v2.runtime.unmarshaller.SAXConnector.startElement(SAXConnector.java:135)
        at com.sun.xml.internal.bind.unmarshaller.DOMScanner.visit(DOMScanner.java:229)
        at com.sun.xml.internal.bind.unmarshaller.DOMScanner.visit(DOMScanner.java:266)
        at com.sun.xml.internal.bind.unmarshaller.DOMScanner.visit(DOMScanner.java:235)
        at com.sun.xml.internal.bind.unmarshaller.DOMScanner.visit(DOMScanner.java:266)
        at com.sun.xml.internal.bind.unmarshaller.DOMScanner.visit(DOMScanner.java:235)
        at com.sun.xml.internal.bind.unmarshaller.DOMScanner.visit(DOMScanner.java:266)
        at com.sun.xml.internal.bind.unmarshaller.DOMScanner.visit(DOMScanner.java:235)
        at com.sun.xml.internal.bind.unmarshaller.DOMScanner.visit(DOMScanner.java:266)
        at com.sun.xml.internal.bind.unmarshaller.DOMScanner.visit(DOMScanner.java:235)
        at com.sun.xml.internal.bind.unmarshaller.DOMScanner.scan(DOMScanner.java:112)
        at com.sun.xml.internal.bind.unmarshaller.DOMScanner.scan(DOMScanner.java:95)
        at com.sun.xml.internal.bind.unmarshaller.DOMScanner.scan(DOMScanner.java:88)
        at com.sun.xml.internal.bind.v2.runtime.BinderImpl.associativeUnmarshal(BinderImpl.java:146)
        at com.sun.xml.internal.bind.v2.runtime.BinderImpl.unmarshal(BinderImpl.java:117)
        at org.docx4j.openpackaging.parts.JaxbXmlPartXPathAware.unmarshal(JaxbXmlPartXPathAware.java:316)
        at org.docx4j.openpackaging.parts.JaxbXmlPart.getJaxbElement(JaxbXmlPart.java:130)
        at pptx4j.PPTXConverter.create(Converter.java:83)
        at Starter.main(Starter.java:17)
Exception in thread "main" java.lang.NullPointerException
        at pptx4j.PPTXConverter.create(PPTXConverter.java:83)
        at Starter.main(Starter.java:17)

As addition slideLayout1.xml exists with content and i can use it to create a new slide.

I hope someone can give me a hint . If additional informations are necessary, ask please.

UPDATE

I used version 3.0.1, so I updated to 3.2.1 and changed my code a bit. Now the NullPointerException ist gone but I still get an IllegalArgumentException for layoutPart.getContents().getCSld():

INFO  JaxbXmlPart - Lazily unmarshalling /ppt/slideLayouts/slideLayout1.xml
INFO  JaxbXmlPartXPathAware - For org.docx4j.openpackaging.parts.PresentationML.SlideLayoutPart, unmarshall via binder
DEBUG JaxbXmlPartXPathAware - info: com.sun.xml.internal.bind.v2.runtime.BinderImpl
ERROR JaxbXmlPartXPathAware - Unknown type of result: class javax.xml.transform.dom.DOMResult
java.lang.IllegalArgumentException: Unknown type of result: class javax.xml.transform.dom.DOMResult
Solution

  • The problem were certain dependencies between libraries that I use. Unfortunately, I can not say for which library. Only with saxon and docx4j it works now. If I can reproduce my problem, I will add it here.

    @JasonPlutext Thank you for your answer and your hints!