Eclipse, NetBeans and
IntelliJ IDEA are three most used and well-known Java IDEs. Eclipse and NetBeans are completely free; there is a free Community Edition of IDEA, and the Ultimate Edition costs money. All three of those are excellent IDEs with lots of features.
If you want to build Swing GUIs, then NetBeans has a great GUI builder. Eclipse unfortunately does not come with a GUI builder, but you can get the free
Google WindowBuilder Pro as a plug-in which works also very well.
NetBeans and IDEA have great support for
Maven projects; Eclipse needs an additional plug-in for Maven support. IDEA is very good for Scala development. NetBeans comes with very good out-of-the-box support for Java EE projects (in my opinion better than Eclipse). In my experience, NetBeans is better for working with non-Java languages than Eclipse, such as JavaScript.
Java Studio Creator is a project that died years ago. It's not useful anymore.