org.bytedeco.arrow_dataset

Class ExpressionEvaluator

java.lang.Object

org.bytedeco.javacpp.Pointer

org.bytedeco.arrow_dataset.ExpressionEvaluator

All Implemented Interfaces:

AutoCloseable

Direct Known Subclasses:

TreeEvaluator

@Namespace(value="arrow::dataset")
 @Properties(inherit=arrow_dataset.class)
public class ExpressionEvaluator
extends Pointer

Interface for evaluation of expressions against record batches.

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
ExpressionEvaluator(Pointer p) Pointer cast constructor.

Method Summary

Modifier and Type	Method and Description
DatumResult	Evaluate(Expression expr, RecordBatch batch)
DatumResult	Evaluate(Expression expr, RecordBatch batch, MemoryPool pool) Evaluate expr against each row of a RecordBatch.
RecordBatchResult	Filter(Datum selection, RecordBatch batch)
RecordBatchResult	Filter(Datum selection, RecordBatch batch, MemoryPool pool)
RecordBatchIterator	FilterBatches(RecordBatchIterator unfiltered, Expression filter)
RecordBatchIterator	FilterBatches(RecordBatchIterator unfiltered, Expression filter, MemoryPool pool) \brief Wrap an iterator of record batches with a filter expression.
static ExpressionEvaluator	Null() construct an Evaluator which evaluates all expressions to null and does no filtering

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, getPointer, getPointer, getPointer, getPointer, hashCode, isNull, isNull, limit, limit, malloc, maxBytes, maxPhysicalBytes, memchr, memcmp, memcpy, memmove, memset, offsetof, offsetof, parseBytes, physicalBytes, 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

ExpressionEvaluator

public ExpressionEvaluator(Pointer p)

Pointer cast constructor. Invokes Pointer.Pointer(Pointer).

Method Detail

Evaluate

@ByVal
public DatumResult Evaluate(@Const @ByRef
                                    Expression expr,
                                    @Const @ByRef
                                    RecordBatch batch,
                                    MemoryPool pool)

Evaluate expr against each row of a RecordBatch. Returned Datum will be of either SCALAR or ARRAY kind. A return value of ARRAY kind will have length == batch.num_rows() An return value of SCALAR kind is equivalent to an array of the same type whose slots contain a single repeated value. expr must be validated against the schema of batch before calling this method.

Evaluate

@ByVal
public DatumResult Evaluate(@Const @ByRef
                                    Expression expr,
                                    @Const @ByRef
                                    RecordBatch batch)

Filter

@ByVal
public RecordBatchResult Filter(@Const @ByRef
                                        Datum selection,
                                        @SharedPtr @Cast(value={"","std::shared_ptr<arrow::RecordBatch>"})
                                        RecordBatch batch,
                                        MemoryPool pool)

Filter

@ByVal
public RecordBatchResult Filter(@Const @ByRef
                                        Datum selection,
                                        @SharedPtr @Cast(value={"","std::shared_ptr<arrow::RecordBatch>"})
                                        RecordBatch batch)

FilterBatches

@ByVal
public RecordBatchIterator FilterBatches(@ByVal
                                                 RecordBatchIterator unfiltered,
                                                 @SharedPtr @ByVal
                                                 Expression filter,
                                                 MemoryPool pool)

\brief Wrap an iterator of record batches with a filter expression. The resulting iterator will yield record batches filtered by the given expression. \note The ExpressionEvaluator must outlive the returned iterator.

FilterBatches

@ByVal
public RecordBatchIterator FilterBatches(@ByVal
                                                 RecordBatchIterator unfiltered,
                                                 @SharedPtr @ByVal
                                                 Expression filter)

Null

@SharedPtr
public static ExpressionEvaluator Null()

construct an Evaluator which evaluates all expressions to null and does no filtering