Ask HN: What Tools/IDEs do you use for large Java Projects?

I am working on a Java project with 2 million lines of Java code. It is a maven project and some plugins generate source code during the build process.

I am using Intellij and some times it seems very slow even on quad core i7 with SSD. I have tried Netbeans and it is slow too. I have wasted entire day trying to import the project in to eclipse. It does not like some maven plugins and it does not compile.

What do you use for large Java projects.