#HTTP

March 26, 2023

Content-Disposition with Unicode Filenames in Java: Fixing the IllegalArgumentException

If your download endpoint returns an IllegalArgumentException complaining about a code point outside the range 0–255, the culprit is ISO-8859-1. HTTP headers don't accept raw UTF-8, so Content-Disposition needs percent-encoded filenames and the filename* parameter. This post shows the minimal Java / Spring fix.

• HTTP
• Java