Where to write Java programs?

Question

Java

Answer 1

Some other IDE's (Just to throw options on the table)

Netbeans, Eclipse, Dr. Java,
Processing (For UI).

Answer 2

IntelliJ IDEA, Community version, is a good IDE for Java.

Answer 3

Personally I use Eclipse, as it's also compatible with many other languages. It does however depend on what needs you have and what you're already familiar with. The suggestions from the other guys are great, but I suggest you start by figuring out what you want to do, then find the IDE that suits those needs.