https://trends.google.com/trends/explore?date=today%205-y&q=...
Unfortunate, because it had (has?) a great Swing and UML editor, built-in for free.
Maybe I'm wrong and it's awesome now, but I haven't used it for a while in favor of Eclipse, and now, IntelliJ. This graph illustrates the IDE popularity between Intellij and Netbeans. IntelliJ became preferred over Netbeans about mid 2014.
https://trends.google.com/trends/explore?date=all&geo=US&q=i...
IMHO Netbeans was ahead of idea in many ways. But since they didn't buy commenteers to hype their product it's pretty much nowhere, at least I don't know anyone who uses it.
You can't stop IntelliJ from saving work. I like to kick of a build, and work on some new stuff while it's going on without saving until the build completes. That workflow is impossible in IntelliJ. You have to down tools, for a long build with lots of tests that can make IntelliJ slower over all. IntelliJ generally more responsive for most work, but that's because it's not using Java's type system to find errors as you work, errors are deferred, which often means they take longer over all to fix.
Much much better full text search. I can search through multiple projects. Not just root.
Square selection.
(I personally still use Eclipse)
When you can get it all in memory, you get the benefits of eclipse refactoring, when you can't you don't.
Ability to write code that is safe to refactor is one of the great things about Java, so it's a shame if you can't benefit from that.
Intellij does that a little bit of incremental compilation. They half integrated the eclipse Java compiler at some point but they never really made using it a thing. Most projects just hand off compilatio to Gradle or maven, which means you lose a lot of time waiting for that and dealing with various caches in intellij and gradle/maven getting out of sync with each other. The process for fixing that generally involves boiling the oceans and running the CPU at 400% for a few minutes.
Eclipse compiles two orders of magnitudes faster when you have it properly setup. I'm not exaggerating. It's really good at this. Intellij users have never seen this level of performance. I've tried to explain it a few times to users that insisted they had intellij configured just right. The minimum execution for a unit test after a 1 character code change is the key benchmark for this. Run a test, change something trivial, run it again. If that takes more than half a second and has a noticeable delay, it's not fast. Eclipse user to be closer to 50-100ms. Even on a (now) ten year old laptop. With intellij, it's closer to 3-5 seconds. They have improved things over the years but it never got even close to that level of performance.
I never needed to fiddle with "command line shortener" ridiculousness in Eclipse.
Better code navigation and discovery. Eclipse always finds everything, every called and callee to depth. Same with inheritance. Even where Idea has same views, for some reason they hide it and only former Eclipse users stumble on it.
Actually safe refactorings. Idea occasionally "refactors" by creating bugs.
I had some cases where Idea simply formats code wrong. And it was impossible to configure to formát it right.
Also, Eclipse compile by default. It is ridiculous to have to remember to press shortcut to compile in modern IDE. I know it is configurable, but still ridiculous default.
Square selection.