The Felix Fileinstall and Config Admin are two essential components of Apache Karaf runtime. I wrote about issues with array/list handling already twice. In 2015 and 2022. While earlier post was about syntax, later was about troubles with parsing of stored entries. Turns out, I’ve found a reason.
A long time ago I wrote an post about Configuration Admin and Arrays. Recently I attempted to use this feature with openHAB and I found that it doesn’t work with its configuration framework.
Apache Felix Configuration Admin (CM) is widely used component which is responsible for provisioning of one of most common OSGi services. Main responsibility of it is to bring configurations stored in property files to services. While digging into Felix CM code I have found that it is able to create scalar values of certain type ie. Long, but also more complex structures such Array or Vector. The biggest issue was that I couldn’t find any way to force it to create array from string representation. Thanks to google ( FELIX-4431 found on 4th page of results) and debugger goodnes I finally managed to do it. Here is recipe how to proceed. ...
Piątego lutego miałem niekłamaną przyjemność podziwiać Jacka Laskowskiego prezentującego temat Praktyczne wprowadzenie do OSGi i Enterprise OSGi. Link do filmiku z prezentacją Jacka znajdziecie na Jego blogu. Tymczasem, poniżej wideo z Karafem. :-)
Few months ago I’ve read an article written by my friend Jacek Laskowski - Enterprise OSGi runtime setup with Apache Aries Blueprint. In his article Jacek describes which bundles should be installed to get the blueprint working. As IBM employee Jacek can always promote IBM WebSphere in version X or Y which started (or will start) supporting blueprint as dependency injection mechanism. That’s not fine for these who do not run IBM producs and want something light. As you know, Aries and OSGi Blueprint is an alternative for old-fashion Spring approach.
One of bigest benefits of Java is byte code manipulation. You can change everything you want in your application without touching source code. That’s usefull for many cases, starting from legacy code, where we can’t simply modify and recompile library up to modern applications where aspects can be used to handle runtime exceptions. The most popular project is AspectJ which is part of Eclipse ecosystem, in this post I going to show you how to use AspectJ with Karaf.
Management of OSGi - let’s face it - is not very hard. The OSGi environment is clearly defined and that gives programmers many mechanisms to create administrative tools. The problem begins when we would like to use only one tool to manage few projects or artifacts of different types. I know this from personal experience because when I run Camel, ActiveMQ and CXF every from them provides own administration console. Every of them requires own security configuration, looks differently, have own dependencies and so on. ...