smile.io

Class Arrow

java.lang.Object

smile.io.Arrow

public class Arrow
extends java.lang.Object

Apache Arrow is a cross-language development platform for in-memory data. It specifies a standardized language-independent columnar memory format for flat and hierarchical data, organized for efficient analytic operations on modern hardware.

Constructor Summary

Constructors

Constructor and Description
Arrow() Constructor.
Arrow(int batch) Constructor.

Method Summary

Modifier and Type	Method and Description
static void	allocate(long limit) Creates the root allocator.
smile.data.DataFrame	read(java.io.InputStream input, int limit) Reads a limited number of records from an arrow file.
smile.data.DataFrame	read(java.nio.file.Path path) Reads an arrow file.
smile.data.DataFrame	read(java.nio.file.Path path, int limit) Reads an arrow file.
smile.data.DataFrame	read(java.lang.String path) Reads a limited number of records from an arrow file.
smile.data.DataFrame	read(java.lang.String path, int limit) Reads a limited number of records from an arrow file.
void	write(smile.data.DataFrame df, java.nio.file.Path path) Writes the DataFrame to a file.

Methods inherited from class java.lang.Object

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

Constructor Detail

Arrow

public Arrow()

Constructor.

Arrow

public Arrow(int batch)

Constructor.

Parameters:

batch - the number of records in a record batch.

Method Detail

allocate

public static void allocate(long limit)

Creates the root allocator. The RootAllocator is responsible for being the master bookeeper for memory allocations.

Parameters:

limit - memory allocation limit in bytes.

read

public smile.data.DataFrame read(java.nio.file.Path path)
                          throws java.io.IOException

Reads an arrow file.

Parameters:

path - an Apache Arrow file path.

Throws:

java.io.IOException

read

public smile.data.DataFrame read(java.nio.file.Path path,
                                 int limit)
                          throws java.io.IOException

Reads an arrow file.

Parameters:

path - an Apache Arrow file path.

Throws:

java.io.IOException

read

public smile.data.DataFrame read(java.lang.String path)
                          throws java.io.IOException,
                                 java.net.URISyntaxException

Reads a limited number of records from an arrow file.

Parameters:

path - an Apache Arrow file path or URI.

Throws:

java.io.IOException

java.net.URISyntaxException

read

public smile.data.DataFrame read(java.lang.String path,
                                 int limit)
                          throws java.io.IOException,
                                 java.net.URISyntaxException

Reads a limited number of records from an arrow file.

Parameters:

path - an Apache Arrow file path or URI.

limit - reads a limited number of records.

Throws:

java.io.IOException

java.net.URISyntaxException

read

public smile.data.DataFrame read(java.io.InputStream input,
                                 int limit)
                          throws java.io.IOException

Reads a limited number of records from an arrow file.

Parameters:

input - an Apache Arrow file input stream.

limit - reads a limited number of records.

Throws:

java.io.IOException

write

public void write(smile.data.DataFrame df,
                  java.nio.file.Path path)
           throws java.io.IOException

Writes the DataFrame to a file.

Throws:

java.io.IOException