LayoutCollector.getStartPageIndex(para) is throwing Null Pointer Exception on the first try, and returns result on retry

Aspose.Words Product Family
1

Hey, Please find my code below

    LayoutCollector lc = new LayoutCollector(doc);

    for (Paragraph para : paragraphs) {
            if (lc.getStartPageIndex(para) > pageNumber || para.isEndOfDocument()) {
               // some action
            }
    }

Here, lc.getStartPageIndex(para) s throwing Null Pointer Exception, i also tried evaluating lc.getStartPageIndex(paragraphs.get(0)) and lc.getStartPageIndex(paragraphs.get(1)) … etc

Every time when i evaluate first, it throws exception, but when i re-evaluate the same line it works fine.

It Does not happen with all the document.

PFAoriginal-upload (22).docx (6.5 MB)

2

@1623751199347 I was unable to reproduce the specified issue on the latest version of Aspose.Words with the following code

for (Paragraph para : document.getFirstSection().getBody().getParagraphs()) {
	int paraInd = lc.getStartPageIndex(para);
	System.out.println(paraInd);
	System.out.println(para.isEndOfDocument());
}

Could you please explain how you get paragraphs in your piece of code?

3

This is how i collect paragraphs

NodeCollection paragraphs = (NodeCollection) doc.getChildNodes(NodeType.PARAGRAPH, true);

i also tried with doc.getFirstSection().getBody().getParagraphs() , it throws exception, we are using aspose version 20.2

4

@1623751199347 Unfortunately, I was unable to reproduce the issue. Please try to run your code with the latest 22.1 version.

5

we dont have the latest version now, can you try it in my version and check the issue is reproducible ?

6

@1623751199347 Yes, on 20.2 release this error is reproduced.

7

Do you know why its happenin?
In Debug mode, when i try to evaluate the statement it errored with NPE, but when re-evaluate the same thing it is getting succeeded,

is there any workaround for this ?

8

@1623751199347 You can close LayoutCollector first call in try{} block and the second one in catch{}. But this is a weird workaround. I would recommend you to update to the newest version.

9

okay, i will do that…Thank you

10

Can you please provide an example here?

11

@ashishb888

LayoutCollector lc = new LayoutCollector(doc);
for (Paragraph para : paragraphs) {
  int paraInd;
  try{
    paraInd = lc.getStartPageIndex(para);
  } catch (Exception e)  {
    paraInd = lc.getStartPageIndex(para);
  }
  System.out.println(paraInd);
}

Once again, this is a weird workaround. I would recommend you to update to the newest version.

1 Like