de.lmu.ifi.dbs.elki.datasource.bundle

Class BundleWriter

java.lang.Object

de.lmu.ifi.dbs.elki.datasource.bundle.BundleWriter

public class BundleWriter
extends java.lang.Object

Write an object bundle stream to a file channel. Bundle streams that add new columns are not supported.

Since:

0.5.5

Author:

Erich Schubert

Field Summary

Fields

Modifier and Type	Field and Description
private static int	INITIAL_BUFFER Initial buffer size.
private static Logging	LOG Class logger for the bundle writer.
static int	MAGIC Random magic number.

Constructor Summary

Constructors

Constructor and Description
BundleWriter()

Method Summary

Modifier and Type	Method and Description
private java.nio.ByteBuffer	ensureBuffer(int size, java.nio.ByteBuffer buffer, java.nio.channels.WritableByteChannel output) Ensure the buffer is large enough.
private void	flushBuffer(java.nio.ByteBuffer buffer, java.nio.channels.WritableByteChannel output) Flush the current write buffer to disk.
void	writeBundleStream(BundleStreamSource source, java.nio.channels.WritableByteChannel output) Write a bundle stream to a file output channel.
private ByteBufferSerializer<?>[]	writeHeader(BundleStreamSource source, java.nio.ByteBuffer buffer, java.nio.channels.WritableByteChannel output) Write the header for the given stream to the stream.

Methods inherited from class java.lang.Object

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

Field Detail

LOG

private static final Logging LOG

Class logger for the bundle writer.

INITIAL_BUFFER

private static final int INITIAL_BUFFER

Initial buffer size.

See Also:

Constant Field Values

MAGIC

public static final int MAGIC

Random magic number.

See Also:

Constant Field Values

Constructor Detail

BundleWriter

public BundleWriter()

Method Detail

writeBundleStream

public void writeBundleStream(BundleStreamSource source,
                              java.nio.channels.WritableByteChannel output)
                       throws java.io.IOException

Write a bundle stream to a file output channel.

Parameters:

source - Data source

output - Output channel

Throws:

java.io.IOException - on IO errors

flushBuffer

private void flushBuffer(java.nio.ByteBuffer buffer,
                         java.nio.channels.WritableByteChannel output)
                  throws java.io.IOException

Flush the current write buffer to disk.

Parameters:

buffer - Buffer to write

output - Output channel

Throws:

java.io.IOException - on IO errors

ensureBuffer

private java.nio.ByteBuffer ensureBuffer(int size,
                                         java.nio.ByteBuffer buffer,
                                         java.nio.channels.WritableByteChannel output)
                                  throws java.io.IOException

Ensure the buffer is large enough.

Parameters:

size - Required size to add

buffer - Existing buffer

output - Output channel

Returns:

Buffer, eventually resized

Throws:

java.io.IOException - on IO errors

writeHeader

private ByteBufferSerializer<?>[] writeHeader(BundleStreamSource source,
                                              java.nio.ByteBuffer buffer,
                                              java.nio.channels.WritableByteChannel output)
                                       throws java.io.IOException

Write the header for the given stream to the stream.

Parameters:

source - Bundle stream

buffer - Buffer to use for writing

output - Output channel

Returns:

Array of serializers

Throws:

java.io.IOException - on IO errors