The Scheduling Helper

The Scheduling Helper is the component that executes your scheduled work. When a trigger fires (for a one-time or recurring job), the scheduler locates the helper that supports the job’s command and invokes it.

Interface

A SchedulingHelper exposes three methods:

1. `CompletionStage<Void> execute(String id, SchedulingCommand cmd)`

Invoked at the scheduled time. The id is the triggerIdentifier from the JobSpecification, and cmd is the triggerCommand.

2. `CompletionStage<Void> lateExecute(String id, SchedulingCommand cmd, Duration overThreshold)`

Invoked instead of execute(…) only when the job has opted in to late execution handling via lateExecutionThreshold and the threshold is exceeded at run time. The default implementation delegates to execute(…).

3. `boolean supports(SchedulingCommand cmd)`

Determines whether this helper handles the given command type. When multiple helpers are present, the scheduler chooses the first helper that returns true.