ai.rapids.cudf

Class ParquetChunkedReader

java.lang.Object

ai.rapids.cudf.ParquetChunkedReader

All Implemented Interfaces:

AutoCloseable

public class ParquetChunkedReader
extends Object
implements AutoCloseable

Provide an interface for reading a Parquet file in an iterative manner.

Constructor Summary

Constructors

Constructor and Description
ParquetChunkedReader(long chunkSizeByteLimit, File filePath) Construct the reader instance from a read limit and a file path.
ParquetChunkedReader(long chunkSizeByteLimit, long passReadLimit, ParquetOptions opts, File filePath) Construct the reader instance from a read limit, a ParquetOptions object, and a file path.
ParquetChunkedReader(long chunkSizeByteLimit, long passReadLimit, ParquetOptions opts, HostMemoryBuffer buffer, long offset, long len) Construct the reader instance from a read limit and a file already read in a memory buffer.
ParquetChunkedReader(long chunkSizeByteLimit, ParquetOptions opts, DataSource ds) Construct a reader instance from a DataSource
ParquetChunkedReader(long chunkSizeByteLimit, ParquetOptions opts, File filePath) Construct the reader instance from a read limit, a ParquetOptions object, and a file path.
ParquetChunkedReader(long chunkSizeByteLimit, ParquetOptions opts, HostMemoryBuffer buffer, long offset, long len) Construct the reader instance from a read limit and a file already read in a memory buffer.

Method Summary

Modifier and Type	Method and Description
void	close()
boolean	hasNext() Check if the given file has anything left to read.
Table	readChunk() Read a chunk of rows in the given Parquet file such that the returning data has total size does not exceed the given read limit.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ParquetChunkedReader

public ParquetChunkedReader(long chunkSizeByteLimit,
                            File filePath)

Construct the reader instance from a read limit and a file path.

Parameters:

chunkSizeByteLimit - Limit on total number of bytes to be returned per read, or 0 if there is no limit.

filePath - Full path of the input Parquet file to read.

ParquetChunkedReader

public ParquetChunkedReader(long chunkSizeByteLimit,
                            ParquetOptions opts,
                            File filePath)

Construct the reader instance from a read limit, a ParquetOptions object, and a file path.

Parameters:

chunkSizeByteLimit - Limit on total number of bytes to be returned per read, or 0 if there is no limit.

opts - The options for Parquet reading.

filePath - Full path of the input Parquet file to read.

ParquetChunkedReader

public ParquetChunkedReader(long chunkSizeByteLimit,
                            long passReadLimit,
                            ParquetOptions opts,
                            File filePath)

Construct the reader instance from a read limit, a ParquetOptions object, and a file path.

Parameters:

chunkSizeByteLimit - Limit on total number of bytes to be returned per read, or 0 if there is no limit.

passReadLimit - Limit on the amount of memory used for reading and decompressing data or 0 if there is no limit

opts - The options for Parquet reading.

filePath - Full path of the input Parquet file to read.

ParquetChunkedReader

public ParquetChunkedReader(long chunkSizeByteLimit,
                            ParquetOptions opts,
                            HostMemoryBuffer buffer,
                            long offset,
                            long len)

Construct the reader instance from a read limit and a file already read in a memory buffer.

Parameters:

chunkSizeByteLimit - Limit on total number of bytes to be returned per read, or 0 if there is no limit.

opts - The options for Parquet reading.

buffer - Raw Parquet file content.

offset - The starting offset into buffer.

len - The number of bytes to parse the given buffer.

ParquetChunkedReader

public ParquetChunkedReader(long chunkSizeByteLimit,
                            long passReadLimit,
                            ParquetOptions opts,
                            HostMemoryBuffer buffer,
                            long offset,
                            long len)

Construct the reader instance from a read limit and a file already read in a memory buffer.

Parameters:

chunkSizeByteLimit - Limit on total number of bytes to be returned per read, or 0 if there is no limit.

passReadLimit - Limit on the amount of memory used for reading and decompressing data or 0 if there is no limit

opts - The options for Parquet reading.

buffer - Raw Parquet file content.

offset - The starting offset into buffer.

len - The number of bytes to parse the given buffer.

ParquetChunkedReader

public ParquetChunkedReader(long chunkSizeByteLimit,
                            ParquetOptions opts,
                            DataSource ds)

Construct a reader instance from a DataSource

Parameters:

chunkSizeByteLimit - Limit on total number of bytes to be returned per read, or 0 if there is no limit.

opts - The options for Parquet reading.

ds - the data source to read from

Method Detail

hasNext

public boolean hasNext()

Check if the given file has anything left to read.

Returns:

A boolean value indicating if there is more data to read from file.

readChunk

public Table readChunk()

Read a chunk of rows in the given Parquet file such that the returning data has total size does not exceed the given read limit. If the given file has no data, or all data has been read before by previous calls to this function, a null Table will be returned.

Returns:

A table of new rows reading from the given file.

close

public void close()

Specified by:

close in interface AutoCloseable