If you don't use an IDE for Java programming you're not making use of one its most positive traits: Its very well documented.
In Eclipse, the distance between you and all of Java's standard libraries its literally just a shortcut, ctrl+spacebar. Hovering over any standard classes grants you access to all of its documentation. You get very nice highlights about what's wrong on your code, easy automatic imports, class outlines, refactoring tools, and a big, BIG etc.
You don't even need to learn all of the IDE to get going. Just use what you need and you'll be fine.
I mean, you could have Oracle's site open in a browser and looking for the doc there but really, its not necessary. Javadoc is nicely integrated in Eclipse, and you'll learn better from official docs (and the sources) rather than Googling around features that someone might or might not know exactly how they work.