Package org.apache.drill.exec.vector.complex.fn

Class SeekableBAIS

java.lang.Object

java.io.InputStream

java.io.ByteArrayInputStream

org.apache.drill.exec.vector.complex.fn.SeekableBAIS

All Implemented Interfaces:

Closeable, AutoCloseable, org.apache.hadoop.fs.PositionedReadable, org.apache.hadoop.fs.Seekable

public class SeekableBAIS
extends ByteArrayInputStream
implements org.apache.hadoop.fs.Seekable, org.apache.hadoop.fs.PositionedReadable

A ByteArrayInputStream that supports the HDFS Seekable API.

Field Summary

Fields inherited from class java.io.ByteArrayInputStream

buf, count, mark, pos

Constructor Summary

Constructors

Constructor	Description
SeekableBAIS(byte[] buf)
SeekableBAIS(byte[] buf, int offset, int length)

Method Summary

Modifier and Type	Method	Description
long	getPos()
int	read(long position, byte[] buffer, int offset, int length)	Read up to the specified number of bytes, from a given position within a file, and return the number of bytes read.
void	readFully(long position, byte[] buffer)	Read number of bytes equal to the length of the buffer, from a given position within a file.
void	readFully(long position, byte[] buffer, int offset, int length)	Read the specified number of bytes, from a given position within a file.
void	seek(long pos)
boolean	seekToNewSource(long targetPos)

Methods inherited from class java.io.ByteArrayInputStream

available, close, mark, markSupported, read, read, readAllBytes, readNBytes, reset, skip, transferTo

Methods inherited from class java.io.InputStream

nullInputStream, read, readNBytes

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.hadoop.fs.PositionedReadable

maxReadSizeForVectorReads, minSeekForVectorReads, readVectored

Constructor Details

SeekableBAIS

public SeekableBAIS(byte[] buf,
 int offset,
 int length)

SeekableBAIS

public SeekableBAIS(byte[] buf)

Method Details

seek

public void seek(long pos)
          throws IOException

Specified by:

seek in interface org.apache.hadoop.fs.Seekable

Throws:

IOException

getPos

public long getPos()
            throws IOException

Specified by:

getPos in interface org.apache.hadoop.fs.Seekable

Throws:

IOException

seekToNewSource

public boolean seekToNewSource(long targetPos)
                        throws IOException

Specified by:

seekToNewSource in interface org.apache.hadoop.fs.Seekable

Throws:

IOException

read

public int read(long position,
 byte[] buffer,
 int offset,
 int length)
         throws IOException

Read up to the specified number of bytes, from a given position within a file, and return the number of bytes read. This does not change the current offset of a file, and is thread-safe. Warning: Not all filesystems satisfy the thread-safety requirement.

Specified by:

read in interface org.apache.hadoop.fs.PositionedReadable

Parameters:

position - position within file

buffer - destination buffer

offset - offset in the buffer

length - number of bytes to read

Returns:

actual number of bytes read; -1 means "none"

Throws:

IOException - IO problems.

readFully

public void readFully(long position,
 byte[] buffer,
 int offset,
 int length)
               throws IOException

Read the specified number of bytes, from a given position within a file. This does not change the current offset of a file, and is thread-safe. Warning: Not all filesystems satisfy the thread-safety requirement.

Specified by:

readFully in interface org.apache.hadoop.fs.PositionedReadable

Parameters:

position - position within file

buffer - destination buffer

offset - offset in the buffer

length - number of bytes to read

Throws:

IOException - IO problems.

EOFException - the end of the data was reached before the read operation completed

readFully

public void readFully(long position,
 byte[] buffer)
               throws IOException

Read number of bytes equal to the length of the buffer, from a given position within a file. This does not change the current offset of a file, and is thread-safe. Warning: Not all filesystems satisfy the thread-safety requirement.

Specified by:

readFully in interface org.apache.hadoop.fs.PositionedReadable

Parameters:

position - position within file

buffer - destination buffer

Throws:

IOException - IO problems.

EOFException - the end of the data was reached before the read operation completed