Xor News

Quite possibly my best single line of code ever. Certainly my best single line of Java ever.
And it’s in a unit test.


private static String W = "Президент Буш";


What’s yours?

Here are some that are noteworthy and funny:

• Is it Christmas – http://isitchristmas.com – Funny as it tracks the timezones across the globe, really only has much to do on one day per year though. But that one day is coming up soon, so start checking in daily.
• Is it Dark Outside – http://isitdarkoutside.com – Whopping funny. Works every day of the year.
• Umbrella Today – http://umbrellatoday.com – I guess they are hawking an iPhone app, but I really enjoyed how the interface pulls you in a little bit at a time. And if you visit for the first time on a rainy day (or just put in a Seattle, Washington zip code), that rainy-day graphic is stunning.

It’s all about hiding the complexity. Do something hard with your software but don’t make the users suffer just you did.

A recent tweet from my pal #eknock complaining about some juicy ORA-06550: line 1, column 7 reminded me of these error codes that an old-cgi script of min produces:

• Bad disktype code ORA-99xxx
• CTXUSER not enabled ORA-010xxx
• Flagellular misfire ORA-910xxx
• Nascent order lost code: ORA-82xxx
• Ferrule injector not found: ORA-14xxx

Of course it’s just a perl script and the system had nothing to do with Oracle. Just one of those little things that can be done to throw snoopers off the trail.

Yesterday I attended the first-ever Hadoop World, sponsored by Cloudera and held in The Roosevelt Hotel in New York City. I took an early Amtrak train up to the big city and a late train back that same night. The conference was well attended, over 500 big-data heads were there and the organizers did a fantastic job.

Some of the best stuff was just hearing about how other folks are using Hadoop. I also enjoyed hearing about the sizes of other people’s big-data problems. There were three tracks, so I only heard 1/3 of what took place, but here are some notes on what I did hear after the break.

It was a great day, a long day, glad I went. (more…)

Upgrade to WP 2.8 broke the comments permalinks, 2.8.1 didn’t help. The user would get an error page after posting a comment (comment was posted) and clicking on any of the links to a comment went to the-url-for-the-post/comments-page-1#comment-id which would get you a 404. In the admin settings discussion area there is a (new?) setting to break comments up into pages of 50. Turning this off fixed the problem. I’ve never had 50 non-spam comments so that shouldn’t hurt too much. Plus I don’t think I ever turned it on in the first place.

This screen cast covers Scaling Rails apps using Rack and Metal and is an execellent tutorial on both subjects. Jason Pollack, one of the Rails Envy guys, does a superb job explaining how rack and metal work in Rails 2.3.

Reading an interesting paper on d-Left Hashing (pdf link) by Bonomi, Mitzenmacher, et. al. This is a space and effeciency improvement on Bloom filters. Wondering how it could be incorporated into a Hadoop mapfile to avoid scanning compressed blocks for keys that aren’t present. Maybe the work in hbase on o.a.h.hbase.io.BloomFilterMapFile would provide good clues. Need to understand the dynamic bit reassignment stuff first though.

I lost the entire blog today with a carelessly placed argument to
‘rm -rf’. Ironically I was trying to delete some old backups of
this blog. It turned out I deleted everything.

Most of it was restored from backup. Some few pictures are still
missing though.

I am an Emacs weenie. I really can’t get much work done without emacs. I
have tried other things.

* vi/vim – I can use it and I try to learn a new command every once in a
while
* Textmate – mkay. But I like Emacs. Plus Emacs is free.
* Visual Slick Edit – The parts that are like Emacs are nice. Emacs is
free.
* Netbeans – Almost can be configured to work like Emacs.
* Eclipse – No. I. Just. Can’t. Do. It. Very. Sorry.

So I am making this post from Emacs. Carbon Emacs 22.1 on Mac OS X.
Using weblogger mode. It turned out to be easy. The hard part was
figuring out what the “endpoint URL” was supposed to be
(/blog/xmlrpc.php for this Wordpress blog). And enabling the Markdown
plugin. Yeah, that was tricky — had to click a checkbox.

See ya later lame textarea edit box and lame wordpress markup style. We
hardly knew ye.

We are starting to use thrift and needed an ant build recipe. Here’s what we came up with. It works good and the only thing that looks like an abstraction leakage to me is that I needed to know the package, the java namespace, for the resultant generated thrift code and the name of one of the thrift generated files. The primary goal was to eliminate running the thrift generator when the generated code is newer than the .thrift files. There isn’t a one to one mapping between .thrift files and generated output so if any of the generated stuff is newer than any of the thrift then it all gets recreated.

I also didn’t want to have to copy the thrift output to someplace else, so a javac target was added to just treat the “gen-java” thrift output as a new source directory for direct java compilation. The normal ant target to compile the java code can now just depend on “thrift-gen”.

  <property name="thrift.dir" value="${basedir}/src/thrift"/>
  <property name="thrift.out.dir" value="${basedir}/src/gen-java"/>
  <property name="thrift.package" value="your/package/name"/>

  <!-- thrift files -->
  <fileset id="thrift.files" dir="${thrift.dir}">
    <include name="**/*.thrift"/>
  </fileset>
  <!-- Determint if thrift generated java is up to date -->
  <target name="thrift-init">
    <dependset>
      <srcfileset refid="thrift.files"/>
      <targetfileset dir = "${thrift.out.dir}/${thrift.package}">
        <include name="**/*.java"/>
      </targetfileset>
    </dependset>
    <available file="${thrift.out.dir}/${thrift.package}/Foo.java"
               property="thrift.uptodate"/>
  </target>

  <!-- Generate thrift java -->
  <target name="thrift-gen" depends="thrift-init" unless="thrift.uptodate">
    <pathconvert property="thrift.file.list" refid="thrift.files"
               pathsep=" " dirsep="/">
    </pathconvert>
    <echo message="Running thrift generator on ${thrift.file.list}"/>
    <exec executable="thrift" dir="${basedir}" failonerror="true">
      <arg line="--strict --gen java -o src ${thrift.file.list}"/>
    </exec>
  </target>