Yesterday I posted a user function for compressing/decompressing files using parallel processes in ODI. The same code you can pick up and use from an OWB process flow. Invoking the java function from within a Java activity from within the flow.
The JAR used in the example below can be downloaded here, from the process flow OWB invokes the main method within the ZipFile class for example - passing the parameters to the function for the input, output directories and also the number of threads. The parameters are passed as a string in OWB, each parameter is wrapped in ?, so we have a string like ?param1?param2?param3? and so on. In the example I pass the input directory d:\inputlogs as the first parameter and d:\outputzips as the second, the number of processes used is 4 - I have escaped my backslash in order to get this to work on Windows.
The classpath has the JAR file with the class compiled in it and the classpath value can be specified specified on the activity, carefully escaping the path if on windows.
Then you can define the actual class to use;
That's it, pretty easy. The return value from the method will use the exit code from your java method - normally 0 is failure and other values are error (so if you exit the java using a specific error code value you can return this code into a variable in OWB or perform a complex transition condition). Any standard output/error is also capture from within the OWB activity log in the UI, for example below you can see an exception that was thrown and also messages output to the standard output/error;
That's a quick insight to the java activity in OWB.