iText failure with adding elements with 5.5.4 - itext

Question

I have code that has broken with the 5.5.4 update. I have internally confirmed it works with previous 3 versions...
adding the element causes a null pointer exception
reader = new PdfReader('Users/Me/Documents/a.pdf')
stamper = new PdfStamper(reader, new FileOutputStream('some_file'))
cb = stamper.getOverContent(1)
ct = new ColumnText(cb)
ct.setSimpleColumn(120f, 48f, 200f, 600f)
pz = new Paragraph ( new Phrase (20, 'Hello World!', f) )
ct.addElement(pz)
ct.go()
stamper.close()
reader.close()
john
great new book btw Bruno...
UPDATE
I did indeed miss out a bit of code before, and I was trying to isolate the issue in a longer piece of code
This version does exhibit the issue for me:
bf = BaseFont.createFont(BaseFont.HELVETICA_BOLD, 'Cp1252', BaseFont.EMBEDDED)
f = new Font(bf, 13)
reader = new PdfReader(src')
stamper = new PdfStamper(reader, new FileOutputStream(dest))
cb = stamper.getOverContent(1)
ct = new ColumnText(cb)
ct.setSimpleColumn(120f, 48f, 200f, 600f)
pz = new Paragraph ( 'Hello World!' )
ct.addElement(pz)
ct.go()
stamper.close()
reader.close()
ct.addText(chunk) works but not addElement() in 5.5.4, does in 5.5.1 - 5.5.3

Answer 1

your code sample is incomplete. For instance: it misses the PDF to which you are trying to add extra words (I took a simple "Hello World" pdf) and it misses some definitions, such as the declaration of the f variable (I took the default font, which is Helvetica, 12pt).
When I fill out the blanks you left in your question, I end up with the following code:
public void manipulatePdf(String src, String dest) throws IOException, DocumentException {
PdfReader reader = new PdfReader(src);
PdfStamper stamper = new PdfStamper(reader, new FileOutputStream(dest));
PdfContentByte cb = stamper.getOverContent(1);
ColumnText ct = new ColumnText(cb);
ct.setSimpleColumn(120f, 48f, 200f, 600f);
Font f = new Font();
Paragraph pz = new Paragraph(new Phrase(20, "Hello World!", f));
ct.addElement(pz);
ct.go();
stamper.close();
reader.close();
}
This code results in the PDF colum_text_phrase.pdf, a document that now shows the words "Hello World!" twice, once because these words were already present on the original document, and once because we added these words using the adapted code from your question.
In other words: I can not reproduce the problem you are reporting, hence your question is unanswerable.
Note that I don't understand this line:
Paragraph pz = new Paragraph(new Phrase(20, "Hello World!", f));
Why would you create a Phrase and then wrap it inside a Paragraph?
Why not either use a Phrase, or a Paragraph? For instance:
Paragraph pz = new Paragraph(20, "Hello World!", f);
Edit:
Based on your edit, I have adapted the ColumnTextPhrase example. I still wasn't able to reproduce the problem, not by using:
pz = new Paragraph ( 'Hello World!' )
(which is what you wrote), nor by using:
pz = new Paragraph ( 'Hello World!', f )
(which is what you probably meant to write).
EDIT:
Using the file you shared in your comment, I was able to reproduce the problem. I also understand why the problem occurs: you have a file that is a Tagged PDF. Now you are adding content that isn't tagged. Older iText versions allow you to do such an inconsiderate operation, the latest iText version apparently prevents you from doing something that goes against "good taste". I'll pass this to development to find out if this was intentional or not.