What is the most efficient Java Collections library?
A few years ago, I did a lot of Java and had the impression back then that trove is the best (most efficient) Java Collections implementation. But when I read the answers to the question ‘Most useful free Java libraries?‘ I noticed that trove is hardly mentioned. So which Java Collections library is best now?
UPDATE: To clarify, I mostly want to know what library to use when I have to store millions of entries in a hash table etc. (need a small runtime and memory footprint).
From inspection, it looks like Trove is just a library of collections for primitive types – it’s not like it’s meant to be adding a lot of functionality over the normal collections in the JDK.
Personally (and I’m biased) I love Guava (including the former Google Java Collections project). It makes various tasks (including collections) a lot easier, in a way which is at least reasonably efficient. Given that collection operations rarely form a bottleneck in my code (in my experience) this is ‘better’ than a collections API which may be more efficient but doesn’t make my code as readable.
Given that the overlap between Trove and the Guava is pretty much nil, perhaps you could clarify what you’re actually looking for from a collections library.