Package org.elasticsearch.common.io

Class Channels

java.lang.Object

org.elasticsearch.common.io.Channels

public final class Channels
extends Object

Field Summary

Fields

Modifier and Type	Field	Description
static final int	WRITE_CHUNK_SIZE	The maximum chunk size for writes in bytes

Method Summary

Modifier and Type	Method	Description
static int	readFromFileChannel(FileChannel channel, long channelPosition, byte[] dest, int destOffset, int length)	read length bytes from position of a file channel.
static byte[]	readFromFileChannel(FileChannel channel, long position, int length)	read length bytes from position of a file channel
static int	readFromFileChannel(FileChannel channel, long channelPosition, ByteBuffer dest)	read from a file channel into a byte buffer, starting at a certain position.
static void	readFromFileChannelWithEofException(FileChannel channel, long channelPosition, byte[] dest, int destOffset, int length)	read length bytes from position of a file channel.
static int	readFromFileChannelWithEofException(FileChannel channel, long channelPosition, ByteBuffer dest)	read from a file channel into a byte buffer, starting at a certain position.
static void	writeToChannel(byte[] source, int offset, int length, FileChannel channel, long channelPosition)	Writes part of a byte array to a WritableByteChannel at the provided position.
static void	writeToChannel(byte[] source, int offset, int length, WritableByteChannel channel)	Writes part of a byte array to a WritableByteChannel
static void	writeToChannel(byte[] source, FileChannel channel, long channelPosition)	Writes part of a byte array to a WritableByteChannel at the provided position.
static void	writeToChannel(byte[] source, WritableByteChannel channel)	Writes part of a byte array to a WritableByteChannel
static void	writeToChannel(ByteBuffer byteBuffer, WritableByteChannel channel)	Writes a ByteBuffer to a WritableByteChannel

Methods inherited from class java.lang.Object

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

Field Details

WRITE_CHUNK_SIZE

public static final int WRITE_CHUNK_SIZE

The maximum chunk size for writes in bytes

See Also:

• Constant Field Values

Method Details

readFromFileChannel

public static byte[] readFromFileChannel(FileChannel channel,
 long position,
 int length)
                                  throws IOException

read length bytes from position of a file channel

Throws:

IOException

readFromFileChannelWithEofException

public static void readFromFileChannelWithEofException(FileChannel channel,
 long channelPosition,
 byte[] dest,
 int destOffset,
 int length)
                                                throws IOException

read length bytes from position of a file channel. An EOFException will be thrown if you attempt to read beyond the end of file.

Parameters:

channel - channel to read from

channelPosition - position to read from

dest - destination byte array to put data in

destOffset - offset in dest to read into

length - number of bytes to read

Throws:

IOException

readFromFileChannel

public static int readFromFileChannel(FileChannel channel,
 long channelPosition,
 byte[] dest,
 int destOffset,
 int length)
                               throws IOException

read length bytes from position of a file channel.

Parameters:

channel - channel to read from

channelPosition - position to read from

dest - destination byte array to put data in

destOffset - offset in dest to read into

length - number of bytes to read

Returns:

total bytes read or -1 if an attempt was made to read past EOF. The method always tries to read all the bytes that will fit in the destination byte buffer.

Throws:

IOException

readFromFileChannelWithEofException

public static int readFromFileChannelWithEofException(FileChannel channel,
 long channelPosition,
 ByteBuffer dest)
                                               throws IOException

read from a file channel into a byte buffer, starting at a certain position. An EOFException will be thrown if you attempt to read beyond the end of file.

Parameters:

channel - channel to read from

channelPosition - position to read from

dest - destination ByteBuffer to put data in

Returns:

total bytes read

Throws:

IOException

readFromFileChannel

public static int readFromFileChannel(FileChannel channel,
 long channelPosition,
 ByteBuffer dest)
                               throws IOException

read from a file channel into a byte buffer, starting at a certain position.

Parameters:

channel - channel to read from

channelPosition - position to read from

dest - destination ByteBuffer to put data in

Returns:

total bytes read or -1 if an attempt was made to read past EOF. The method always tries to read all the bytes that will fit in the destination byte buffer.

Throws:

IOException

writeToChannel

public static void writeToChannel(byte[] source,
 WritableByteChannel channel)
                           throws IOException

Writes part of a byte array to a WritableByteChannel

Parameters:

source - byte array to copy from

channel - target WritableByteChannel

Throws:

IOException

writeToChannel

public static void writeToChannel(byte[] source,
 int offset,
 int length,
 WritableByteChannel channel)
                           throws IOException

Writes part of a byte array to a WritableByteChannel

Parameters:

source - byte array to copy from

offset - start copying from this offset

length - how many bytes to copy

channel - target WritableByteChannel

Throws:

IOException

writeToChannel

public static void writeToChannel(byte[] source,
 FileChannel channel,
 long channelPosition)
                           throws IOException

Writes part of a byte array to a WritableByteChannel at the provided position.

Parameters:

source - byte array to copy from

channel - target WritableByteChannel

channelPosition - position to write at

Throws:

IOException

writeToChannel

public static void writeToChannel(byte[] source,
 int offset,
 int length,
 FileChannel channel,
 long channelPosition)
                           throws IOException

Writes part of a byte array to a WritableByteChannel at the provided position.

Parameters:

source - byte array to copy from

offset - start copying from this offset

length - how many bytes to copy

channel - target WritableByteChannel

channelPosition - position to write at

Throws:

IOException

writeToChannel

public static void writeToChannel(ByteBuffer byteBuffer,
 WritableByteChannel channel)
                           throws IOException

Writes a ByteBuffer to a WritableByteChannel

Parameters:

byteBuffer - source buffer

channel - channel to write to

Throws:

IOException