protected static String getWatermarkFromPreviousWorkUnits ( SourceState state , String watermark ) { if ( state . getPreviousWorkUnitStates ( ) . isEmpty ( ) ) { return ComplianceConfigurationKeys . NO_PREVIOUS_WATERMARK ; } return state . getPreviousWorkUnitStates ( ) . get ( 0 ) . getProp ( watermark , ComplianceConfigurationKeys . NO_PREVIOUS_WATERMARK ) ; }
Fetches the value of a watermark given its key from the previous run .