[PDFBOX-1101] Improve JavaCC Grammar and Preflight to manage Xref stream object

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.7.0
• Fix Version/s: 1.7.0
• Component/s: Preflight
• Assignee: Eric Leleu
• Reporter: Eric Leleu
• Created: 18/Aug/11 10:59
• Updated: 29/May/12 16:21
• Resolved: 27/Aug/11 11:59

Description

Until PDF 1.4, keywords "xref" and "trailer" were mandatory at the end of the PDF File to know where object are located into the PDF Body.
However, according to my understanding of the PDF Reference 1.5 and 1.7, this two entries can be referenced as object stream.
Because of the PDF/A-1 specification is based on the PDF 1.4, our JavaCC parser check that the file contains trailer entries and extract these trailers to process some controls after Syntax Validation.

TODO :

• Check XRef and Trailer needs in the PDFReference 1.4 to 1.7
• implement new XRef and Trailer managment rules in preflight.