@Override public KeyedStateRow map(Tuple2<K, V> t) throws Exception { int keyGroup = KeyGroupRangeAssignment.assignToKeyGroup(t.f0, maxParallelism); ByteArrayOutputStreamWithPos os = new ByteArrayOutputStreamWithPos(); DataOutputViewStreamWrapper ov = new DataOutputViewStreamWrapper(os); RocksDBUtils.writeKeyGroup(keyGroup, keygroupPrefixBytes, ov); RocksDBUtils.writeKey(t.f0, keySerializer, os, ov, false); RocksDBUtils.writeNameSpace(VoidNamespace.INSTANCE, VoidNamespaceSerializer.INSTANCE, os, ov, false); os.close(); return new KeyedStateRow(stateName, os.toByteArray(), InstantiationUtil.serializeToByteArray(valueSerializer, t.f1)); } }