ExternallyInducedSource.CheckpointTrigger (Flink : 2.0-SNAPSHOT API)

Enclosing interface:

ExternallyInducedSource<T,CD>
```
public static interface ExternallyInducedSource.CheckpointTrigger
```
Through the CheckpointTrigger, the source function notifies the Flink source operator when to trigger the checkpoint.

- Method Summary
  
  All Methods Instance Methods Abstract Methods
  Modifier and Type Method Description
  
  void triggerCheckpoint(long checkpointId)
  Triggers a checkpoint.

- Method Detail
  - triggerCheckpoint
```
void triggerCheckpoint(long checkpointId)
                throws FlinkException
```
    Triggers a checkpoint. This method should be called by the source when it sees the event that indicates that a checkpoint should be triggered.
    When this method is called, the parallel operator instance in which the calling source function runs will perform its checkpoint and insert the checkpoint barrier into the data stream.
    
    Parameters:
    
    checkpointId - The ID that identifies the checkpoint.
    
    Throws:
    
    FlinkException - Thrown when the checkpoint could not be triggered, for example because of an invalid state or errors when storing the checkpoint state.