[PDFBOX-1744] Be resilient to PDFs with missing version info

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 1.8.2
• Fix Version/s: 1.8.3, 2.0.0
• Component/s: Parsing
• Environment: PDFBox 1.8.2, IntelliJ IDEA 12.1.6, Mac OS X 10.7.5, Java 1.7, Maven 2.2.1
• Assignee: Andreas Lehmkühler
• Reporter: Chris Bamford
• Created: 10/Oct/13 11:27
• Updated: 30/Nov/13 17:02
• Resolved: 28/Oct/13 18:13

Description

Proposed addition to 1.8.2 -> pdfbox/src/main/java/org/apache/pdfbox/pdfparser/PDFParser.java -> parseHeader() to default the PDF version to 1.4 in situations where it is missing (yes, there really are docs out there like this!).
This prevents an exception caused from a negative substring offset calculation: "String index out of range: -3"

I have floated the question on the [e-mail] mailing list (10th October 2013) and it was suggested I default the PDF version to 1.4 in this scenario. I have tested it locally and it works (apparently PDFBox doesn't take the version number into account anyway).

Now over to you guys to decide if this is a good idea or not in the wider scope.

Should you give the green light, I attach:
1) a sample file which causes the exception
2) a patch file
3) patching instructions.

My goal is text extraction, even on broken files (if possible).