This the worker framework for workers that transform parameter input files to parameter output files. It is an abstract base class. The application must, at a minimum, implement the process method to process parameter data.
- The worker reads the parameter definition file (well the App does that).
- The worker accepts a parameter definition record from the dealer and uses that to construct a mapping between parameter ids in the file and tree parameters in the application.
- The worker accepts the variable definition records and creates a map of name -> {unit/value} pairs. This map is accessible from derived classes which can take or leave it or anything in the middle. The logic behind this is that the point of the application may be to use different variable values. Note that utility methods available to derived classes can provide the data from the message data. Note, however that it is the file data that goes into the output file.
The worker than requests and gets parameter data. Using the mappings previously constructed, tree parameters are loaded with the data in each event.
- process (the user method) is then called and the user must do the application specific computations that result in output parameers
- On return from process, the parameters are marshalled from the tree parameters and sent to the farmer.
- When data are exhausted an end record is pushed to the farmer.
