io.cdap.cdap.api.dataset.lib.partitioned

Interface StatePersistor

All Known Implementing Classes:

DelegatingStatePersistor

public interface StatePersistor

Defines how some state will be persisted/managed.

Method Summary

Modifier and Type	Method and Description
void	persistState(byte[] state) Writes the serialized bytes of the state of the partition consuming process.
byte[]	readState()

Method Detail

readState

@Nullable
byte[] readState()

Returns:

the serialized bytes of the state of the partition consuming process; return null to indicate a fresh state of consuming (defaults to starting from the beginning).

persistState

void persistState(byte[] state)

Writes the serialized bytes of the state of the partition consuming process. The bytes written in this method should be available in the following call to readBytes(DatasetContext).

Parameters:

state - the bytes to persist