org.apache.asterix.metadata.api

Interface IMetadataEntityTupleTranslator<T>

All Known Implementing Classes:

AbstractTupleTranslator, CompactionPolicyTupleTranslator, DatasetTupleTranslator, DatasourceAdapterTupleTranslator, DatatypeTupleTranslator, DataverseTupleTranslator, ExternalFileTupleTranslator, FeedPolicyTupleTranslator, FeedTupleTranslator, FunctionTupleTranslator, IndexTupleTranslator, LibraryTupleTranslator, NodeGroupTupleTranslator, NodeTupleTranslator

public interface IMetadataEntityTupleTranslator<T>

Interface for translating the representation of metadata entities (datasets, types, etc.) from their Java object representation to a serialized representation in a Hyracks tuple, and vice versa. Implementations of this interface are intended to be used within an IMetadataNode.

Method Summary

Methods

Modifier and Type	Method and Description
T	getMetadataEntityFromTuple(org.apache.hyracks.dataflow.common.data.accessors.ITupleReference tuple) Transforms a metadata entity of type T from a given tuple to a Java object (deserializing the appropriate field(s) in the tuple as necessary).
org.apache.hyracks.dataflow.common.data.accessors.ITupleReference	getTupleFromMetadataEntity(T metadataEntity) Serializes the given metadata entity of type T into an appropriate tuple representation (i.e., some number of fields containing bytes).

Method Detail

getMetadataEntityFromTuple

T getMetadataEntityFromTuple(org.apache.hyracks.dataflow.common.data.accessors.ITupleReference tuple)
                             throws MetadataException,
                                    IOException

Transforms a metadata entity of type T from a given tuple to a Java object (deserializing the appropriate field(s) in the tuple as necessary).

Parameters:

tuple - Tuple containing a serialized representation of a metadata entity of type T.

Returns:

A new instance of a metadata entity of type T.

Throws:

MetadataException

IOException

getTupleFromMetadataEntity

org.apache.hyracks.dataflow.common.data.accessors.ITupleReference getTupleFromMetadataEntity(T metadataEntity)
                                                                                             throws MetadataException,
                                                                                                    IOException

Serializes the given metadata entity of type T into an appropriate tuple representation (i.e., some number of fields containing bytes).

Parameters:

metadataEntity - Metadata entity to be written into a tuple.

Throws:

IOException

MetadataException