Sunday, March 15, 2009

Pass Variables between Java & BPEL Process

When using Java embedding activity in a BPEL process for processing BPEL variables , it will be required to pass the variables between Java and the BPEL process. In such cases, you can use
the following methods to get/set the variables;

getVariableData(bpelVariable); method will fetch that variable value to be used inside the Java embedding activity

setVariableData(bpelVariable, Value); method sets the Value (processed in the Java embedding activity) to the bpelVariable, which can be used in the BPEL process for further processing.

However, the variable datatype conversions should be properly handled in BPEL process and Java embedding activity.

Saturday, March 14, 2009

Lost BPEL Instances? - Use Force Dehydration

There will be many instances when it will be really puzzling to find out whether the BPEL instance was triggered or not, where we often say that the "BPEL instance is lost". Actually, in reality, the BPEL process could have resulted in some kind of exception during the process which gets suppressed completely by the BPEL PM and the instance neither gets persisted or dehydrated in the orabpel schema nor shown up in BPELConsole.

This will be really troublesome, as we will not be able to identify whether the problem lies in the external system driving the BPEL instance or within the BPEL process itself after consumption of data. In such cases, you can use the checkpoint(); Java method inside a Java embedding activity to force the instance to be dehydrated as soon as the instance gets triggered in BPEL. This will ensure that the BPEL instance is shown up in the BPEL console if it is instantiated. You can use the following piece of code in your BPEL process to force dehydration.

<bpelx:exec name="CheckPointOne" language="java" version="1.5">

Now, all your BPEL instances will be available in the BPELConsole for debugging issues that are not actually propagated/thrown to BPELConsole by the OPMN.

However, there are certain drawbacks while using the force dehydration mechanism, as this will cause drop in performance of the BPEL process during run-time due to the additional overhead of persisting the instance whenever this method is called. So please make justified use of this method before using this.