UPDATE: Sadly, it seems that the installer below now ships with ads embedded within JDownloader itself as seen below. However there are no toolbars or standalone adware programs included. Given that reputable software clients like Evernote (with a free account) include ads within their UI, I still recommend this installer.
UPDATE 2: Some commenters are claiming the installer has a virus. Here’s the report on the most recent 64-bit installer after it was uploaded to virustotal.com. As you can see, only 1/54 antivirus packages detected anything malicious.
UPDATE 3 (2015-01-12): I just completed an installation on a Windows 7 SP1 x64 machine with Panda Free Antivirus and got no security warnings whatsoever.
For the uninitiated, JDownloader is a download client for direct download (e.g. Uploaded.to) and video sites (e.g. YouTube) that allows you to grab files you have the links for without keeping your browser open at the file URL. Unfortunately, the app’s new web installer has adware that’s flagged as malware by some security software including Windows Defender, Microsoft Security Essentials, and AVG.*
Thankfully, you can grab the full, adware-free installers from the following links:
*It’s arguable that this is par for the course for a download client written Java