Version 0.6.0 of the Watchmaker Framework for Evolutionary Computation is now available for download.  This release incorporates several minor changes that I’ve been making over the last few months.  Consult the changelog for full details, but here are the highlights:

Numerous Improvements to the Evolution Monitor and other Swing Components

The Watchmaker Swing library provides a collection of GUI components that simplify the process of building user interfaces for evolutionary programs. These components have received many improvments for version 0.6.0. As well as controls for manipulating evolution parameters while the program is running, the library also provides an Evolution Monitor component. This provides real-time information about the state of the program, including a view of the fittest candidate so far and a graph showing changes in population fitness over time.

Upgraded to Uncommons Maths 1.2

This means even faster RNGs are available for you to use. It also means that we now use the Uncommons Maths Probability class rather than duplicating it in the framework (this means you may have to change some imports in your code when upgrading from Watchmaker 0.5.x).

Caching Fitness Evaluator

Version 0.6.0 introduces the CachingFitnessEvaluator class. This is a wrapper that provides caching for existing FitnessEvaluator implementations. The results of fitness evaluations are cached so that if the same candidate is evaluated twice, the expense of the fitness calculation can be avoided the second time. The cache uses weak references in order to avoid memory leakage.

Caching of fitness values can be a useful optimisation in situations where the fitness evaluation is expensive and there is a possibility that some candidates will survive from generation to generation unmodified. Programs that use elitism are one example of candidates surviving unmodified. Another scenario is when the configured evolutionary operator does not always modify every candidate in the population for every generation.

Caching of fitness scores is provided as an option rather than as the default Watchmaker Framework behaviour because caching is only valid when fitness evaluations are isolated and repeatable. An isolated fitness evaluation is one where the result depends only upon the candidate being evaluated. This is not the case when candidates are evaluated against the other members of the population.

Mona Lisa Example

After seeing Roger Alsing’s evolution of the Mona Lisa, I was inspired to try to reproduce it using the Watchmaker Framework. I didn’t follow Roger’s methodology but I have come up with something similar. My results aren’t as impressive as his latest efforts but may be interesting anyway. This example was actually included in version 0.5.1 but I didn’t draw attention to it. In 0.6.0 I’ve improved performance and used it to demonstrate the Watchmaker GUI components mentioned above.  You can try it for yourself here.  Maybe you can come up with a combination of parameters that works better than the defaults I have provided?

Useful Watchmaker Links

• Download
• Full Changelog
• API Documentation
• Demo Applets: Travelling Salesman, Biomorphs, Sudoku Solver, Mona Lisa
• Forum

If you are new to Evolutionary Computation in Java,  these previous articles may be of interest:

• Practical Evolutionary Computation: An Introduction
• Practical Evolutionary Computation: Implementation
• Practical Evolutionary Computation: Elitism

I read Anthony Goubard’s “Top 10 Unused Java Features” on JavaLobby earlier today.  I agree with some of his selections but I think he missed out a few key features that nobody uses.  Restricting myself to just language features (the API is too huge), here are four more widely unused features of Java.

4. The short data type

You use it? I don’t believe you. Everybody^* uses int when they want integers, even if they don’t need a 32-bit range.

3. Octal Literals

Who uses Octal these days?^** Hexadecimal is a more useful shorthand for binary values.  Worse, the leading-zero notation for Octal literals is just confusing:

int a = 60;
int b = 060;
System.out.println(a + b); // Prints 108.

2. Local Classes

Java has four types of nested class, three of which are widely used.  As well as static nested classes, named inner classes and anonymous inner classes, you can also define named classes within methods, though it’s rare to see one in the wild.

public class TopLevelClass
{
    public void someMethod()
    {
        class LocalClass
        {
            // Some fields and methods here.
        }
 
        LocalClass forLocalPeople = new LocalClass();
    }
}

1. Strict FP

There is probably a programmer out there somewhere for whom Java’s strictfp is vital, but I haven’t met him or her. If you already know what strictfp is used for then you are probably in the top 5% of Java programmers. If you don’t know what strictfp does, here you go, welcome to the top 5%. It’s basically about making sure that your calculations are equally wrong on all platforms.

* OK, maybe you used to be a C programmer.
** Here’s your rhetorical answer.

Related Articles

• A Java Syntax Quirk
• More Stupid Java Tricks
• JavaNG: A Better Java – What would you do?

How do ordinary programmers become famous programmers?  Since I am not already a famous programmer I can’t speak from experience but, from scientific observations of the those programmers who are well-known, I have been able to identify the following five strategies for becoming a “thought leader”:

1. Do Great Things

Build software that everybody uses and you’ll become famous.  Easy.

This is the Torvalds method.  Everybody knows who Linus is because of Linux.  And, just to prove it wasn’t a fluke, he followed up by creating Git.  This approach is not fool-proof though.  Not all great projects become famous and not all famous projects have well-known developers.

2. Talk the Talk

Start a blog, get 100,000 readers, retire on the Adsense revenue.

The best known programmers aren’t necessarily known for their programming.  They may still be good programmers but they made their mark by being excellent communicators.  Joel Spolsky is the poster child for this category.  If it weren’t for Joel’s blog who knows whether Fog Creek Software would be in business at all?  By writing regular common sense about software development and management, and by evangelising the programmer’s utopia that he’s building in New York, Joel keeps his company, its products and its offices in the minds of his hundreds of thousands of readers.

Joel’s StackOverflow business partner, Jeff Atwood, is another example of programmer-turned-A-list-blogger.  I would love to know how to get from 200-reader blog to 100k-reader blog.  I’m sure that in Jeff’s case it has a lot to do with the regular posting schedule that he has maintained over a number of years.  Easy-to-read articles, with a hint of danger, posted several times a week leads to an extensive archive of articles that no doubt brings in a huge amount of Google traffic.

Steve Yegge is somebody else you could look to emulate as a blogger, but if you find yourself writing articles so long that they need a full-page table of contents, it’s probably time to lay off the dope.

3. Write the Book

Next time you are in a job interview or pitching for some consulting work and somebody asks “do you know anything about technology XYZ?”, wouldn’t it be great to be able to respond “actually, I wrote the book Professional XYZ in Action for Dummies in a Nutshell”?

There are thousands of software development books published every year.  Technology books have short life spans and publishers are always on the lookout for potential authors to write a book on the next big thing.  If you can demonstrate basic literacy and sufficient technical knowledge, it could be you.  Just don’t expect to get rich from the royalties.  If you divide the amount that you make by the number of hours you spend writing, you’ll be lucky to come out ahead of minimum wage levels.

It’s a big time commitment for modest direct financial rewards but, if you’re playing the long game, writing a book can lead to other opportunities such as speaking at conferences, providing expert consultancy and more.  You also get the satisfaction of seeing your book on Amazon and, better still, you get to harrass local bookstores by re-enacting the J.R. Hartley Yellow Pages ad.

4. Become a Cult Figure

Jon Skeet was a respected member of the programming community before the advent of StackOverflow but now, as the number one ranked user by some distance, Jon Skeet is a cult.

5. Work at Google

I don’t know whether being a well-known developer gets you a job at Google or if getting a job at Google makes you a well-known developer but either way there are a lot of famous programmers at Google.

Working at Google is like an extra stamp of credibility.  If you don’t work at Google and you say something stupid, people think you are dumb.  If you do work at Google and you say something stupid, people think that you know something that they don’t.