org.aksw.jena_sparql_api.io.endpoint

Interface Destination

All Known Subinterfaces:

FileDestination

All Known Implementing Classes:

DestinationFilter, DestinationFromByteSource, DestinationFromFile, DestinationFromFileCreation, DestinationFromSwitch

public interface Destination

Every destination must be usable as a supplier for input streams. Concretely, a destination can represent any of the following things: (a) an anonymous source of input streams (b) a file that already exists (c) a file that can be generated on request (d) a file under generation and will thus exist is the future (e) a prior filter (for which no output type was yet requested) In a later version we may consider replacing file with 'store' and 'reference' i.e. a reference to a store that will hold the data in the future But then again, this might be too much abstraction - the implication is, that we would need to specify conversions between different kind of stores: "ifNeedsSomeSpecificTypeOfStoreAsInput then provide a policy for converting the input data" Then again, we just require the stores to be file-like, so we never have to deal with specifics of different store.

Author:

raven

Method Summary

Modifier and Type	Method and Description
default void	cancelCreation() Cancel the creation of a destination's byte source.
String	getCreationStatus() Get a description of the creation status.
io.reactivex.rxjava3.core.Single<DestinationFromFile>	materialize(Supplier<Path> preferredPathCallback) Materialize the destination to a given file.
io.reactivex.rxjava3.core.Single<InputStreamSupplier>	prepareStream() This method requests a supplier for inputstreams.
FilterConfig	transferTo(FilterEngine engine)

Method Detail

prepareStream

io.reactivex.rxjava3.core.Single<InputStreamSupplier> prepareStream()

This method requests a supplier for inputstreams. For basic destinations, such as FileDestination, this process does not involve any overhead. However, if the destination represents a workflow, prepareStream may trigger a complex execution. The execution may generate a file from which streams can be obtained, or nothing gets executed at this point, and execution only occur when opening an input stream.

Returns:

getCreationStatus

String getCreationStatus()

Get a description of the creation status.

Returns:

materialize

io.reactivex.rxjava3.core.Single<DestinationFromFile> materialize(Supplier<Path> preferredPathCallback)
                                                           throws IOException

Materialize the destination to a given file. If the destination is already a file it waits until it has been completed. For non-file destinations, the callback is invoked to obtain a preferred file name

Returns:

Throws:

IOException

transferTo

FilterConfig transferTo(FilterEngine engine)

cancelCreation

default void cancelCreation()

Cancel the creation of a destination's byte source. Propagates upstream unless .wrapWithoutCancel() was called