Class S3InputFile

java.lang.Object

dev.hardwood.s3.S3InputFile

All Implemented Interfaces:

InputFile, Closeable, AutoCloseable

public class S3InputFile
extends Object
implements InputFile

InputFile backed by an object in Amazon S3 (or an S3-compatible service).

Each readRange(long, int) call issues a signed HTTP GET request with a byte-range header, so only the requested bytes are transferred.

open() uses a suffix-range GET instead of a HEAD request. This discovers the file length from the Content-Range response header and pre-fetches the Parquet footer (which sits at the end of the file) in the same round-trip — eliminating a separate HEAD request per file.

Thread-safe once open() has been called.

Method Summary

Modifier and Type	Method	Description
void	close()
long	length()	Returns the total size of the file in bytes.
String	name()	Returns an identifier for this file, used in log messages and JFR events.
void	open()	Performs expensive resource acquisition (e.g. memory-mapping, network connect).
ByteBuffer	readRange(long offset, int length)	Read a range of bytes from the file.

Methods inherited from class Object

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

Method Details

open

public void open()
          throws IOException

Description copied from interface: InputFile

Performs expensive resource acquisition (e.g. memory-mapping, network connect). Must be called before InputFile.readRange(long, int) or InputFile.length().

Specified by:

open in interface InputFile

Throws:

IOException - if the resource cannot be acquired

readRange

public ByteBuffer readRange(long offset,
 int length)
                     throws IOException

Description copied from interface: InputFile

Read a range of bytes from the file.

Specified by:

readRange in interface InputFile

Parameters:

offset - the byte offset to start reading from

length - the number of bytes to read

Returns:

a ByteBuffer containing the requested data

Throws:

IOException - if the read fails

length

public long length()

Description copied from interface: InputFile

Returns the total size of the file in bytes.

Specified by:

length in interface InputFile

Returns:

the file size

name

public String name()

Description copied from interface: InputFile

Returns an identifier for this file, used in log messages and JFR events.

Specified by:

name in interface InputFile

Returns:

a human-readable name or path

close

public void close()

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable