@ Override public RocksDBRestoreResult restore ( ) throws IOException , StateMigrationException , RocksDBException { openDB ( ) ; for ( KeyedStateHandle keyedStateHandle : restoreStateHandles ) { if ( keyedStateHandle != null ) { if ( ! ( keyedStateHandle instanceof KeyGroupsStateHandle ) ) { throw new IllegalStateException ( "Unexpected state handle type, " + "expected: " + KeyGroupsStateHandle . class + ", but found: " + keyedStateHandle . getClass ( ) ) ; } this . currentKeyGroupsStateHandle = ( KeyGroupsStateHandle ) keyedStateHandle ; restoreKeyGroupsInStateHandle ( ) ; } } return new RocksDBRestoreResult ( this . db , defaultColumnFamilyHandle , nativeMetricMonitor , - 1 , null , null ) ; }
Restores all key - groups data that is referenced by the passed state handles .