Alternative Java MessageFormat

MessageFormat

I was working on providing I18N support in my Krail project, when I was reminded of the strange characteristics of the standard Java MessageFormat class (java.text.MesssageFormat) ... especially the handling of single quotes.

I thought maybe it had been improved in Java 7, but it seems not.  The javadoc still carries a warning:

Warning:

The rules for using quotes within message format patterns unfortunately have shown to be somewhat confusing. In particular, it isn't always obvious to localizers whether single quotes need to be doubled or not. Make sure to inform localizers about the rules, and tell them (for example, by using comments in resource bundle source files) which strings will be processed by MessageFormat. Note that localizers may need to use single quotes in translated strings where the original version doesn't have them.

The Alternative

I remember being thoroughly confused by MessageFormat and the "solution" offered by the javadoc hardly helpful.  So I started looking for an alternative.  I found quite a few posts also looking for alternatives but still no real solution.  

So I wrote one ... it is based on sl4j, who have a highly tuned message handling routine for logging but which requires the parameter values to be provided in the same order as the message parameters.  That makes perfect sense for logging, but does not work very well for I18N, where different languages put the parameter values in different orders.

So I took the easy option of providing my own MessageFormat class to take the parameters in any order, but then organise them so that the sl4j MessageFormatter can do its work.

The resulting code is here, and its companion test code here.  Even if you have no interest in the Krail project, you may find the alternative MessageFormat useful.

OrientDB deployment

Publishing the V7 Demo

Demo now available 

There is now an online demo of V7.

Last minute snag

I has a situation where everything worked on my desktop, but when deployed to a virtual server, connection to the OrientDB database was being refused.  The error I was getting was:

java.lang.IllegalStateException: Node id is possible to generate only on machine which have at least one network interface with mac address.

at com.orientechnologies.orient.core.util.OHostInfo.getMac(OHostInfo.java:48)

at com.orientechnologies.orient.core.version.OVersionFactory.<clinit>(OVersionFactory.java:32)

at com.orientechnologies.orient.core.storage.impl.local.OTxSegment.<clinit>(OTxSegment.java:68)

at com.orientechnologies.orient.core.storage.impl.local.OStorageLocalTxExecuter.<init>(OStorageLocalTxExecuter.java:53)

at com.orientechnologies.orient.core.storage.impl.local.OStorageLocal.<init>(OStorageLocal.java:111)

at com.orientechnologies.orient.core.engine.local.OEngineLocal.createStorage(OEngineLocal.java:44)

It turns out that my OpenVZ virtual private server (VPS) does not allocate a MAC address - which is why the failure occurred.

This does raise the question why a single node database needs a MAC address, but apparently this question had already been asked - the fix for it was in the latest snapshot.

So, I've updated the code to use OrientDB 1.4.0-SNAPSHOT and that problem is solved.

Enjoy the demo (but I will admit it does not look as good as the Vaadin 7 demo ....)

Vaadin 7 released

Vaadin 7.0.0

It's great to see the Vaadin 7 release finally hit the streets.  I have updated the V7 code to use Vaadin 7.0.0, without any problems.

Demo

I had intended to provide an online demo, and have a server (a VPS to be more specific) all set up and ready to go - but then I ran into a problem with persistence (or to be more accurate, with the VPS set up which is affecting persistence) , so it will have to wait.  Hopefully not for long though.

Persistence

When I started putting the online demo together, I thought it would be interesting to log whether anyone interacts with it.   That meant providing some persistence, so I brought forward my intention to use a database.

I elected to try OrientDB, partly because it provides Object, Graph and Document database options in one.

I will post separately about that experience - but the main obstacle I found was their documentation.  Some of it is quite good, some not so good, but if you Google for it you can very easily end up with different versions of it.  They seem to have moved their code hosting around a bit.

Anyway, if you do want to take a look, do make sure you start the documentation trail here.

It is very early days, and I have only done some trivial tasks with it, but at first sight this database looks simple to use.

Lazy-loading

One thing which did catch me out is the lazy loading of data  ... and it is entirely my fault, as the documentation does say quite clearly that's how it works ... but I fooled myself by looking for values in the debugger;  they were not there of course, because they do not appear until the associated getters are called.

Definitely an RTFM moment that one ....