Free Java PDF Inspector & Debugger
The only free Java PDF inspector that lets you set breakpoints and single-step through PostScript streams — plus COS object tree and XRef table viewers.
JPedal's free PDF Inspector lets Java developers diagnose corrupt, malformed, or misbehaving PDF files. Browse the COS object tree, view XRef tables, and — uniquely — set breakpoints and single-step through the PostScript commands inside a PDF content stream. It is the only free Java PDF inspector with stream-level debugging.
Inspect PDF files in Minutes
- Download the JPedal PDF Inspector for free
- Either double-click launcher.jar or run the following command from the terminal
java -jar launcher.jarView the COS object tree
The JPedal Inspector allows you to inspect the COS object tree of a PDF file
View the XRef tables
The JPedal Inspector allows you to view the XRef table entries and their objects
View the XRef streams
The JPedal Inspector allows you to view the XRef streams entries and their compressed objects according to the sizes of the W array
Single-Step Through PDF PostScript Streams with Breakpoints
JPedal is the only free Java PDF inspector that lets you set breakpoints and single-step through individual PostScript commands inside a PDF content stream — giving you precise control over exactly where in a stream a rendering problem occurs.
Frequently Asked Questions
What is a PDF inspector?
A PDF inspector is a tool that lets developers examine the internal structure of a PDF file, including its COS object tree, XRef tables, and content streams. It is used to diagnose rendering problems, debug corrupt or malformed PDFs, and understand how fonts, images, annotations and pages are represented internally.
How do I debug PDF files in Java?
JPedal's free PDF Inspector lets you load any PDF and browse its COS object tree, view XRef table entries, and single-step through PostScript content streams with breakpoints. The Inspector is available as a free download or as part of the full JPedal Java PDF Library.
What is a COS object tree in a PDF?
COS (Carousel Object Structure) is the low-level object model of a PDF file. Every element in a PDF — fonts, images, annotations, pages, and form fields — is represented as a COS object. Inspecting the COS tree reveals exactly how a PDF is constructed internally.
What is an XRef table in a PDF?
An XRef (cross-reference) table maps object numbers to their byte offsets within the PDF file. It is how PDF readers locate specific objects without scanning the entire file. Corrupt or mismatched XRef tables are a common cause of PDF rendering failures.
How does JPedal Inspector compare to RUPS for PDF debugging?
RUPS is a great tool and both are free so there is no reason not to use both! The unique feature in JPedal PDF Inspector is the visual rendering and single step debugging feature.
Is JPedal's PDF Inspector free to use?
Yes. JPedal's PDF Inspector is available as a free download to help Java developers diagnose PDF issues. No license is required to run the Inspector.