A few years ago whilst working on my MSc thesis I was heavily into R a statistical analysis package which has a functional language feel to it. My friend Marc Hasenbank, a few others and I ran a series of workshops for people wanting an introduction to R. I recently wanted to show this to someone so thought I would post a link. The code from the tutorials can be found here

I have been working on converting our codebase to JUnit, with a secondary aim of trying out JUnitMax.

I ran the Max and quickly discovered that it failed when trying to execute assertions using the Hamcrest hasItems matcher.

The assertion looks something like:

NoSuchMethodException describeMismatch

This error frequently occurs because JUnit packages an older Version of the org.hamcrest.Matcher class which does not have the describeMismatch method.

I dug around a bit in the plugins directory in the eclipse install folder and found that it contains a junit-4.8.2.jar. Happy days I thought, I can simply do what I’ve been getting used to doing for a while and replace it with junit-dep-4.8.2.jar which does not contain the hamcrest classes.

Unfortunately this didn’t quite work. It turns out that you need to call it exactly the same junit-4.8.2.jar. I thought this was because there’s an entry in the MANIFEST.MF file but I tried to change it and that didn’t work too well.

Renaming the Jar file however works a treat and now I have full JUnitMax action on my box.

I’ve posted on the JUnitMax forums about the problem here.

I’ve been using the R language for some years now but didn’t have it installed on my current machine.

TextMate is a great editor to use as it has a custom bundle that gives you syntax highlighting and executes commands for you in the R console.

To install the R bundle:

cd ~/Library/Application\ Support/TextMate/Bundles/
svn co http://svn.textmate.org/trunk/Bundles/R.tmbundle/

Then in TextMate choose Bundles->Bundle Editor->Reload Bundles.

There is one tweak I make which is that I like to press ⌘ + RETURN to execute the current selection in the R console. So edit the bundle and find R.app in the commands and change the key. Also I like it to return back to text mate afterwards, so I add the following to the script:

-e ‘tell application “TextMate” to activate’ \

I also removed the line about setting the current dir. This was a little fiddly – I found that I had to make sure I selected the entire line and cut it then delete, making sure there are no end of line characters. So it looks like this:

# input is selection or document
rawText=”`cat`”
curDir=”
if [[ ${#TM_DIRECTORY} -gt 0 ]]; then
	curDir=”$TM_DIRECTORY”
fi
osascript -e ‘on run(theCode)’ \
		  -e ‘tell application “R” to activate’ \
		  -e ‘tell application “R” to cmd (item 1 of theCode)’ \
		  -e ‘tell application “TextMate” to activate’ \
		  -e ‘end run’ — “$rawText” “$curDir”

All good.

UPDATE: 07/02/2011 – R now comes with a 64bit version so if you are on a macbook you can replace “R” in the code above with “R64″

We just spent a few glorious hours or so trawling the internet and writing old skool jdbc code, to discover this little beauty. Simply upgrade to 10.2.0.5 of the jdbc driver and it goes away.

Thanks to this post http://efreedom.com/Question/1-377745/Oracle-JDBC-Euro-Character we discovered our problem.

For the full details on the euro….

http://www.fileformat.info/info/unicode/char/20ac/index.htm

And if your really bored:

http://www.fileformat.info/info/unicode/char/1f47e/index.htm

Changing entities to be lazy loaded led me to the following problem:

@OneToMany(fetch = FetchType.LAZY)

Caused by: org.hibernate.HibernateException: Javassist Enhancement failed: Thing
	at org.hibernate.proxy.pojo.javassist.JavassistLazyInitializer.getProxy(JavassistLazyInitializer.java:142)
	at org.hibernate.proxy.pojo.javassist.JavassistProxyFactory.getProxy(JavassistProxyFactory.java:72)
	at org.hibernate.tuple.entity.AbstractEntityTuplizer.createProxy(AbstractEntityTuplizer.java:402)
	at org.hibernate.persister.entity.AbstractEntityPersister.createProxy(AbstractEntityPersister.java:3483)
….
Caused by: java.lang.InstantiationException: Thing_$$_javassist_38
	at java.lang.Class.newInstance0(Class.java:340)
	at java.lang.Class.newInstance(Class.java:308)
	at org.hibernate.proxy.pojo.javassist.JavassistLazyInitializer.getProxy(JavassistLazyInitializer.java:139)

Thanks to Kristian I jumped straight to the problem. From the Hibernate docs:

Cat has a no-argument constructor. All persistent classes must have a default constructor (which can be non-public) so that Hibernate can instantiate them using Constructor.newInstance(). It is recommended that you have a default constructor with at least package visibility for runtime proxy generation in Hibernate.

This should probably read “It is essential….”

Anyway now everything is real lazy so happy days.

GET it from http://jruby.org/

There is a download page, download and exract the tar file somehwere.

I put it in /System/Library/Frameworks/JRuby.framework/jruby-1.5.1

I then created a symbolic link to jruby_current

ln -s jruby-1.5.1/ jruby_current

And then simply add it to my ~/.bash_profile

$vi ~/.bash_profile
export PATH=/System/Library/Frameworks/JRuby.framework/jruby_current/bin:$PATH
#Reload the profile…
$. ~/.bash_profile
#Try out jruby…
$jruby -v
jruby 1.5.1 (ruby 1.8.7 patchlevel 249) (2010-06-06 f3a3480) (Java HotSpot(TM) 64-Bit Server VM 1.6.0_17) [x86_64-java]

Now you can add the JRuby SDK to your Java Module in Intellij:

Now you can have ruby and Java in the same project. Awesome.

I find google reader a useful way to aggregate information from many blogs. Particularly convenient is to be able to read these on my iPhone and then mark them as shared. That way I can build up a list of information I am interested in.

This is then conveniently exposed as an RSS feed by google. You can see my shared items at http://www.google.co.uk/reader/shared/jim.barritt for example.

I used to have a sidebar on this site which had a snippet directly from google reader, but it was determined to have its own style. I wanted a wordpress plugin that would do it for me and found “Recommended Reading Google Reader” by C. Murray Consulting

Its the nice “READING” section on my sidebar. Thanks guys! You just saved me from writing my own!

The Fireworks Plugin for IntelliJ allows you to automatically run all your unit tests when you make a change to the code.

Its a well behaved plugin, it allows you to configure wether or not to do this so you can just turn it on or off.

Whilst using it I made a detour to Shave a couple of Yaks. So thought I’d document it here.

I found it was also running some integration tests which relied on the file system and so didn’t work because there doesn’t appear to be a way to specify the working directory (you can specify JVM args so I could use that instead. I submitted an issue.

In the mean time, actually I thought I would rather not run my integration tests. Fortunately Fireworks allows a regex pattern to decide which files are tests.

After some hunting, I found the following post on stack overflow which gave me the clues i needed to include Test but not IntegrationTest.

The solution takes advantage of “lookaround” features of regex. The syntax in question is:

(?!Integration)

The (?! regex ) syntax means negative look ahead. You can put any regex in there. In our case, just “Integration”. This says, something not followed by “Integration”.

The code on stack overflow had some unnescessary syntax at the beginning (^) and I changed the ordering around a bit to make it read more logically.

(.(?!Integration))*Test

The first “^” was unnescessary, and putting the “.” first made it read better i think. The parentheses are to provide some structure (regex groups) more than any functional reason.

So in words, the new expression reads “match any repeating character (.*) not followed by “Integration” (?!Integration)), then only match if “Test” is on the end.

Here is a test case for it (which along with some other regex stuff can be found on Github :

    @Test
    public void matchesUnitTestsButNotIntegrationTests() {
        String expression = “(.(?!Integration))*Test”;
        Pattern pattern = Pattern.compile(expression);
        assertThat(pattern.matcher(“SomeUnitTest”).matches(), is(true));
        assertThat(pattern.matcher(“SomeIntegrationTest”).matches(), is(false));
        assertThat(pattern.matcher(“SomeNonTestClass”).matches(), is(false));
    }

I found it hard to get this to work on the command line with grep. But I’ve got too much YAK HAIR on my floor now!

Now the Yaks are shaved I can go back to putting a system property in to allow my integration test to work.

Whilst playing around with some code analysis I thought it would be useful to be able to output a hyperlink back to a line of code in the IDE console. As it happens, you can “Trick” IntelliJ to do this with the following log statement:

    @Test
    public void canClickOnAFileInTheConsoleAndGoToTheLineOfCode() {
        log.info(String.format(“Check it at %s. (%s.java:%d)”,
            getClass().getName(), getClass().getSimpleName(), 15));
    }

The pattern it seems to match is something like at {classFullName}.{identifier}({classSimpleName}.java)

classFullName has to be a valid class name.
identifier is usually used for the method name, but it can be anything. The full stop is nescessary. So in the example above, I put a space in there and so it reads like a sentance.

Anyone know a another way to do this?

UPDATE:

Actually it seems that you can get something similar if you output a full path name, e.g.:

    File f = new File(“./src/test/resource/testfiles/level_01/level_01_01/file_01_01_A.txt”);
    log.info(f.getAbsolutePath() + “:” + 34);

This will create a link in the output window to the line of the file. Nice.