So, I've got this report on our Jasper Server (6.2.0) which is supposed to get a new logo.
Here's what I do:
1. In Jaspersoft Studio I open the report directly from the server.
2. I change the logo and save the file.
3. When Studio asks if I want to upload to the server I choose "Yes".
4. I click through the wizard without changing anything.
5. I click "Finish" in the wizard
6. "Exception, if you want so see more information look into details
The Stacktrace shows:
Even if I just open and save the file without changing a thing, I get the same error message.
The report works fine both on the server and in Studio. Downloading, editing and uploading of other reports works just fine.
The report consists of a title page and four subreports, all of which can be uploaded.
The source does not have "null", """" (empty string with double quotes) or "''" (empty string with single quotes) in it.