com.faunos.util.io
Class ChannelUtil<E extends RuntimeException>

java.lang.Object
  com.faunos.util.io.ChannelUtil<E>

public class ChannelUtil<E extends RuntimeException>
extends Object

A utility class for reading and writing to

Field Summary

protected ThrowFactory<RuntimeException,E>

exceptionFactory

Constructor Summary

ChannelUtil(Class<E> exceptionClass)

ChannelUtil(ThrowFactory<RuntimeException,E> exceptionFactory)

Method Summary

static ChannelUtil<RuntimeException>	defaultInstance()
void	readRemaining(FileChannel channel, ByteBuffer buffer, long position) Reads bytes from the given file channel into the specified buffer.
void	readRemaining(ReadableByteChannel channel, ByteBuffer buffer) Reads bytes from the given generic channel into the specified buffer.
void	readRemaining(ScatteringByteChannel channel, ByteBuffer[] buffers) Reads bytes from the given scattering channel into the specified buffer array.
void	setSize(FileChannel channel, long size) Sets the file size.
void	transferFrom(FileChannel channel, long position, long count, ReadableByteChannel source) Transfers the specified number of bytes from the given source into the given destination channel.
void	transferTo(FileChannel channel, long position, long count, WritableByteChannel sink) Transfers the specified number of bytes from the given source channel into the given sink.
void	writeRemaining(FileChannel channel, ByteBuffer buffer, long position) Writes the remaining bytes in the given buffer to the specified file channel starting at the specified position.
void	writeRemaining(WritableByteChannel channel, ByteBuffer buffer) Writes the remaining bytes in the given buffer to the specified generic channel.

Methods inherited from class java.lang.Object

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

Field Detail

exceptionFactory

protected final ThrowFactory<RuntimeException,E extends RuntimeException> exceptionFactory

Constructor Detail

ChannelUtil

public ChannelUtil(Class<E> exceptionClass)

ChannelUtil

public ChannelUtil(ThrowFactory<RuntimeException,E> exceptionFactory)

Method Detail

defaultInstance

public static final ChannelUtil<RuntimeException> defaultInstance()

setSize

public void setSize(FileChannel channel,
                    long size)
             throws IOException

Sets the file size. This is a workaround for the fact that you can't increase a file's size trivially through its FileChannel.

Throws:

IOException

readRemaining

public void readRemaining(FileChannel channel,
                          ByteBuffer buffer,
                          long position)
                   throws IOException

Reads bytes from the given file channel into the specified buffer. The number of bytes read is equal to the number of remaining bytes in the specified buffer: if EOF is reached before filling the buffer, an app-specific exception is raised. Bytes are read starting from the specified position. The current position of the file channel is not modified.

Throws:

IOException

See Also:

readRemaining(ReadableByteChannel, ByteBuffer), readRemaining(ScatteringByteChannel, ByteBuffer[])

readRemaining

public void readRemaining(ReadableByteChannel channel,
                          ByteBuffer buffer)
                   throws IOException

Reads bytes from the given generic channel into the specified buffer. The number of bytes read is equal to the number of remaining bytes in the specified buffer: if EOF is reached before filling the buffer, an app-specific exception is raised. Bytes are read starting from the current (possibly implicit) position of the channel. On return, the current position of the channel is incremented by the number of bytes read.

Throws:

IOException

See Also:

readRemaining(ScatteringByteChannel, ByteBuffer[]), readRemaining(FileChannel, ByteBuffer, long)

readRemaining

public void readRemaining(ScatteringByteChannel channel,
                          ByteBuffer[] buffers)
                   throws IOException

Reads bytes from the given scattering channel into the specified buffer array. The number of bytes read is equal to the sum of the of remaining bytes in the given buffers: if EOF is reached before filling the buffers, an app-specific exception is raised. Bytes are read starting from the current (possibly implicit) position of the channel. On return, the current position of the channel is incremented by the number of bytes read.

Throws:

IOException

See Also:

readRemaining(ReadableByteChannel, ByteBuffer), readRemaining(FileChannel, ByteBuffer, long)

writeRemaining

public void writeRemaining(WritableByteChannel channel,
                           ByteBuffer buffer)
                    throws IOException

Writes the remaining bytes in the given buffer to the specified generic channel. The bytes are written starting at the (possibly implicit) current position of the channel. On return, the current position of the channel is incremented by the number of bytes written.

Throws:

IOException

See Also:

writeRemaining(FileChannel, ByteBuffer, long)

writeRemaining

public void writeRemaining(FileChannel channel,
                           ByteBuffer buffer,
                           long position)
                    throws IOException

Writes the remaining bytes in the given buffer to the specified file channel starting at the specified position. This method does not modify the file channel's current position.

Throws:

IOException

See Also:

writeRemaining(WritableByteChannel, ByteBuffer)

transferTo

public void transferTo(FileChannel channel,
                       long position,
                       long count,
                       WritableByteChannel sink)
                throws IOException

Transfers the specified number of bytes from the given source channel into the given sink. The arguments are checked for bounds before invocation.

Parameters:

channel - the source channel

position - the starting position from which bytes will be read

count - the number of bytes to be transfered

sink - the destination channel

Throws:

IOException

transferFrom

public void transferFrom(FileChannel channel,
                         long position,
                         long count,
                         ReadableByteChannel source)
                  throws IOException

Transfers the specified number of bytes from the given source into the given destination channel. The arguments are checked for bounds before invocation. If it turns out the given source does not have enough remaining bytes, then an instance-specific exception is raised.

Parameters:

channel - the destination channel

position - the starting position in the destination channel at which bytes will be written

count - the number of bytes to transfer

source - the source channel

Throws:

IOException