[PDFBOX-2538] avoid "-1 : Unknown error" message in preflight

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.0.0
• Fix Version/s: 2.0.2, 3.0.0 PDFBox
• Component/s: Preflight
• Assignee: Unassigned
• Reporter: Ralf Hauser
• Created: 03/Dec/14 08:25
• Updated: 01/Oct/22 11:20
• Resolved: 01/Oct/22 11:20

Description

e.g. error 4 in PDFBOX-2513

after all, we know what the reason is.

Ideas:
1) create COSStreamException extends IOException in COSStream.java
2) in SinglePageValidationProcess.validateContent() examine the root cause exception type to classify smarter than just ERROR_UNKOWN_ERROR

any other thoughts?