This weblog explains about how to stop creating an empty file from File Adapter.There can be a situation where after mapping you will get a payload having no values.Payload with no values means you have only XML Tags but there is no Data actually, but the receiver file adapter creates a file with just having XML Tags. Here you will find a solution for this through ModuleProcessor Concept.This module throws an exception if the payload has no values and stops executing further otherwise it will continue with normal execution.
The above module is called on Receiver side before CallSAPAdapter module. It checks whether the payload generated after mapping has any values or not. If no values then it will throw a Module Exception and the next module in module tab will not be executed.If the file is not empty then the module will return the ModuleData to the Moduleprocessor.So the next module configured in module processor is executed, in this case CallSAPAdapter. You should not place your module after CallSAPAdapter module,because the last module should be the CallSAPAdapter in File Adapter.
The above is a simple example of making use of module processor. In your module you can access the module data as well as configuration data that you configure in Communocation channel.You can also change the Payload of the ModuleData and return it to ModuleProcessor.But you cant change the configurtion data.