With the release of Drools 5.1 recently, we're happy to announce the first release of Drools Planner (formerly known as Drools Solver).

Most real world planning problems are NP complete. The common algorithm approaches to these kind of problems are either very sub-optimal or suffer from terrible scalibility. Drools Planner implements metaheuristics (such as simulated annealing and tabu search) to deal with these problems efficiently, while making it relatively easy to add additional planning constraints and works with simple domain POJO's.

Take a look at some use cases to understand the complexity of planning problems.

Download Drools Planner to try some of the examples, such as the nurse rostering or exam scheduling example with real world data.

Or read the reference manual.

A side note: The computer sciences research community was rousled a few weeks ago, because of a new proof claiming to answer the P vs NP question once and for all. Here is a good summary of the story.

Although most mathematicians and researchers believe P != NP, there are some that believe P == NP and there will come a big bang in computer science. I wonder what we, the developers, think of it?

I, for one, also think P != NP and believe they'll prove it soon.

A side note: The computer sciences research community was rousled a few weeks ago, because of a new proof claiming to answer the P vs NP question once and for all. Here is a good summary of the story.

Although most mathematicians and researchers believe P != NP, there are some that believe P == NP and there will come a big bang in computer science. I wonder what we, the developers, think of it?

I, for one, also think P != NP and believe they'll prove it soon.

Poor man Geoffery, this looks like a deparete attempt to catch some attention to your post. Maybe the message people are sending is that Drools is not sexy. Leave us alone.

Jan 

Hi Jan. It was indeed an attempt to create some attention and discussion in the programming community about the P vs NP question, but it looks like no one cares. That's OK: programmers don't need it their day jobs and it doesn't look like it will be answered positively and half our programs will become obsolete. Or maybe no one noticed because I posted my reply after the original post was removed from the frontpage.

As for Drools not being sexy... well, just google or twitter search or come on our IRC channel, it's used all over the world. There's also a download count since the 5.1 release (although most users download it directly from the maven repository which aren't added in that download count).