Corrupted & Malformed Excel Files
In production, applications must handle files that were interrupted during download, maliciously malformed, or saved with the wrong extension. Your parser must catch these exceptions cleanly without hanging or crashing the server.
This suite of files tests your parser's absolute resilience. It includes completely empty 0-byte files, severed ZIP streams, renamed archives, and structurally invalid XML documents designed to trigger exceptions like ZipException: Unexpected EOF.
zero byte
An entirely empty 0-byte file. Tests if your parser throws a clean error or crashes with a NullPointer.
renamed from zip
A plain `.zip` text archive simply renamed to `.xlsx`.
truncated
A binary stream severed at 50%, mimicking a broken network upload.
missing workbook xml
Missing the primary `xl/workbook.xml` root relationship file.
missing content types
Missing the mandatory `[Content_Types].xml` manifest.
invalid xml
Contains malformed HTML tags inside an XML structure to break strict DOM parsers.
empty valid workbook
A structurally perfect XLSX file containing exactly zero data rows.
corrupted zip
A file where a block of internal bytes has been randomized, destroying the ZIP integrity.
wrong extension
A valid `.xlsx` file saved with a legacy `.xls` extension.
wrong extension
A valid `.xlsx` saved as `.csv`.
wrong extension
A valid `.xlsx` saved as `.zip`.
Frequently Asked Questions
Use Cases
- Testing parser resilience to ensure malformed files trigger handled exceptions rather than segmentation faults.
- Validating magic-byte (MIME type) detection logic to ensure a `.csv` renamed to `.xlsx` is processed (or rejected) correctly.
- Ensuring network interruption handling correctly identifies truncated payloads.