After looking around for a decent library for playing videos in Java, I\'ve come unstuck. Everyone around is screaming not to use JMF because it\'s outdated, old and require
I can recommend the gstreamer-java bindings. As the name suggests, it wraps the GStreamer API in Java classes. This way you have access to the media-processing graphing capabilities which GStreamer provides. This can be really neat if you want to do more advanced tasks like transcoding.
Also, if I remember correctly, there was a commercial plugin for GStreamer which supported DVD playback and came with a license for the CSS. If this does not matter for your use case you can always go with the open-sourced one, too (the only one I ever needed).