Patrick Lightbody asks whether my Eclipse can do that.
I'll be the first one to admit that Eclipse can be a crappy, unstable, unpredictable gob of software (especially the 3.2 release). Still his list of advantages with using IDEA strikes me as quite unfair as Eclipse can do a lot of those things he mentions.
Let's step through his points and counter what we can:
Way smarter code complete
Can go beyond the basic support provided by eclipse and can even narrow the completion down to only objects that are type-safe. That is: it won't show you a variable that, if selected, would result in a compile error.
Eclipse can do that. Hmf, hide the options that are not type correct? Eclipse suggests the variables of the correct type first, it doesn't hide the other ones, and I wouldn't want it to. What if I want to pass by that compilation error in order to change the type of a variable?
Camel case understanding
When finding classes, doing code complete, or just about anything else, IDEA understands that when you type "fUM" you really mean "fanstasticUserManager". It's a nice touch that saves a lot of typing.
Eclipse can do that. Try it for yourself.
People who write code in IDEA often write code that is not as clean, and that is due to IDEA's built in smart inspections. It can do things like highlight when an "if" statement can be simplified, or when a null check will always be true.
Eclipse is halfway there with its warnings, but this might be your firmest point.
Easy to act on
Once one of these warning or error inspections pop up, IDEA makes it trivial to take action on it and fix it. Got a missing import? Alt-Enter. Have a redundant if statement? Alt-Enter. See an unused parameter? Alt-Enter. Usually IDEA will give you a few options, such as removing the offending code, changing it, or even suppressing the warning for the statement, method, class, project, or globally.
Eclipse does that. Press Ctrl+1.
It knows what you mean
IDEA is smart. It keeps track of how I name my variables and learns over time. At first, if I am creating a new variable of type BananaSundae, it'll recommend bananaSundae, sundae, and banana, in that order. But, over time, if I keep naming my BananaSundaes simply "ba", it'll start prompting that.
Eclipse will not learn from you. It will suggest bananaSundae and sundae, but not any more than that (and personally that suffices for my part).
Best HTML editor in the world
Remember that Eclipse by itself is a plugin-platform, and the Eclipse bundle we're talking about here is a Java-bundle, not a web-design bundle (although it does have complete CSS and HTML language support). If you wanna compare JS and HTML features, check out Aptana.
I'll accept that IDEA has a much higher rate of *just works* satisfaction. Lucky for me I've been working with Eclipse so long that I've learned to deal with its temper and can easily avoid the pitfalls, meaning poorly implemented functionality, lousy plugins, etc. But if you want to compare features and functionality head on, at least give it a fair shot and try out the features in question. Don't base it on your lousy experience with Eclipse 2.4 two years ago.
And don't compare apples with oranges. Eclipse is an open-source platform. If you want to compare it with a commercial product, atleast be gratious enough to compare it with a commercial Eclipse distribution of equal cost.
I haven't used IDEA much myself, but I've seen enough of it to believe that IDEA is a stronger tool and a better platform for the average Java developer. Still I think it's healthy that Eclipse exists as an free alternative with a much wider range of plugins.
I'm planning to run through a number of refactoring patterns with Eclipse and IDEA to see how they compare (it's actually more of a project getting to know IDEA better). More on this in a later post.