Stateful Processor#
| Function that will be invoked as the first method that allows for users to initialize all their state variables and perform other init actions before handling data. |
| Function that will allow users to interact with input data rows along with the grouping key. |
Function called as the last method that allows for users to perform any cleanup or teardown operations. | |
| Optional to implement. Will act as no-op if not defined or no initial state input. |