org.bytedeco.arrow_dataset

Class InMemoryFragment

java.lang.Object

org.bytedeco.javacpp.Pointer

org.bytedeco.arrow_dataset.Fragment

org.bytedeco.arrow_dataset.InMemoryFragment

All Implemented Interfaces:

AutoCloseable

@Namespace(value="arrow::dataset")
 @NoOffset
 @Properties(inherit=arrow_dataset.class)
public class InMemoryFragment
extends Fragment

\defgroup dataset-implementations Concrete implementations \{

\brief A trivial Fragment that yields ScanTask out of a fixed set of RecordBatch.

Nested Class Summary

Nested classes/interfaces inherited from class org.bytedeco.javacpp.Pointer

Pointer.CustomDeallocator, Pointer.Deallocator, Pointer.NativeDeallocator, Pointer.ReferenceCounter

Field Summary

Fields inherited from class org.bytedeco.javacpp.Pointer

address, capacity, limit, position

Constructor Summary

Constructors

Constructor and Description
InMemoryFragment(Pointer p) Pointer cast constructor.
InMemoryFragment(RecordBatchVector record_batches)
InMemoryFragment(RecordBatchVector record_batches, Expression arg1)
InMemoryFragment(Schema schema, RecordBatchVector record_batches)
InMemoryFragment(Schema schema, RecordBatchVector record_batches, Expression arg2)

Method Summary

Modifier and Type	Method and Description
LongOptionalFuture	CountRows(Expression predicate, ScanOptions options) \brief Count the number of rows in this fragment matching the filter using metadata only.
ScanTaskIteratorResult	Scan(ScanOptions options) \brief Scan returns an iterator of ScanTasks, each of which yields RecordBatches from this Fragment.
RecordBatchGeneratorResult	ScanBatchesAsync(ScanOptions options) An asynchronous version of Scan
String	type_name()

Methods inherited from class org.bytedeco.arrow_dataset.Fragment

partition_expression, ReadPhysicalSchema, ToString

Methods inherited from class org.bytedeco.javacpp.Pointer

address, asBuffer, asByteBuffer, availablePhysicalBytes, calloc, capacity, capacity, close, deallocate, deallocate, deallocateReferences, deallocator, deallocator, equals, fill, formatBytes, free, getDirectBufferAddress, getPointer, getPointer, getPointer, getPointer, hashCode, interruptDeallocatorThread, isNull, isNull, limit, limit, malloc, maxBytes, maxPhysicalBytes, memchr, memcmp, memcpy, memmove, memset, offsetAddress, offsetof, offsetof, parseBytes, physicalBytes, physicalBytesInaccurate, position, position, put, realloc, referenceCount, releaseReference, retainReference, setNull, sizeof, sizeof, toString, totalBytes, totalCount, totalPhysicalBytes, withDeallocator, zero

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

InMemoryFragment

public InMemoryFragment(Pointer p)

Pointer cast constructor. Invokes Pointer(Pointer).

InMemoryFragment

public InMemoryFragment(@SharedPtr @ByVal
                        Schema schema,
                        @ByVal
                        RecordBatchVector record_batches,
                        @ByVal(nullValue="arrow::compute::Expression(compute::literal(true))")
                        Expression arg2)

InMemoryFragment

public InMemoryFragment(@SharedPtr @ByVal
                        Schema schema,
                        @ByVal
                        RecordBatchVector record_batches)

InMemoryFragment

public InMemoryFragment(@ByVal
                        RecordBatchVector record_batches,
                        @ByVal(nullValue="arrow::compute::Expression(compute::literal(true))")
                        Expression arg1)

InMemoryFragment

public InMemoryFragment(@ByVal
                        RecordBatchVector record_batches)

Method Detail

Scan

@ByVal
public ScanTaskIteratorResult Scan(@SharedPtr
                                           ScanOptions options)

Description copied from class: Fragment

\brief Scan returns an iterator of ScanTasks, each of which yields RecordBatches from this Fragment. Note that batches yielded using this method will not be filtered and may not align with the Fragment's schema. In particular, note that columns referenced by the filter may be present in yielded batches even if they are not projected (so that they are available when a filter is applied). Additionally, explicitly projected columns may be absent if they were not present in this fragment. To receive a record batch stream which is fully filtered and projected, use Scanner.

Overrides:

Scan in class Fragment

ScanBatchesAsync

@ByVal
public RecordBatchGeneratorResult ScanBatchesAsync(@SharedPtr
                                                           ScanOptions options)

Description copied from class: Fragment

An asynchronous version of Scan

Overrides:

ScanBatchesAsync in class Fragment

CountRows

@ByVal
public LongOptionalFuture CountRows(@ByVal
                                            Expression predicate,
                                            @SharedPtr
                                            ScanOptions options)

Description copied from class: Fragment

\brief Count the number of rows in this fragment matching the filter using metadata only. That is, this method may perform I/O, but will not load data. If this is not possible, resolve with an empty optional. The fragment can perform I/O (e.g. to read metadata) before it deciding whether it can satisfy the request.

Overrides:

CountRows in class Fragment

type_name

@StdString
public String type_name()

Overrides:

type_name in class Fragment