org.xnio.conduits

Class NullStreamSinkConduit

java.lang.Object

org.xnio.conduits.NullStreamSinkConduit

All Implemented Interfaces:

Conduit, SinkConduit, StreamSinkConduit

public final class NullStreamSinkConduit
extends Object
implements StreamSinkConduit

A stream sink conduit which discards all data written to it.

Author:

David M. Lloyd

Constructor Summary

Constructors

Constructor and Description
NullStreamSinkConduit(XnioIoThread writeThread) Construct a new instance.

Method Summary

Modifier and Type	Method and Description
void	awaitWritable() Block until this channel becomes writable again.
void	awaitWritable(long time, TimeUnit timeUnit) Block until this conduit becomes writable again, or until the timeout expires.
boolean	flush() Flush out any unwritten, buffered output.
XnioWorker	getWorker() Get the XNIO worker associated with this conduit.
XnioIoThread	getWriteThread() Get the write thread for this conduit.
boolean	isWriteResumed() Determine whether write notifications are currently enabled.
boolean	isWriteShutdown() Determine whether writes have been fully shut down on this conduit.
void	resumeWrites() Indicate that the conduit's WriteReadyHandler should be invoked as soon as data can be written without blocking.
void	setWriteReadyHandler(WriteReadyHandler handler) Set the handler which should receive readiness notifications.
void	suspendWrites() Indicate that calling the conduit's WriteReadyHandler should be suspended.
void	terminateWrites() Signal that no more write data is forthcoming.
long	transferFrom(FileChannel src, long position, long count) Transfer bytes into this conduit from the given file.
long	transferFrom(StreamSourceChannel source, long count, ByteBuffer throughBuffer) Transfers bytes from the given channel source.
void	truncateWrites() Terminate writes and discard any outstanding write data.
void	wakeupWrites() Indicate that the conduit's WriteReadyHandler should be invoked immediately, and then again as soon as data can be written without blocking.
int	write(ByteBuffer src) Writes a sequence of bytes to this conduit from the given buffer.
long	write(ByteBuffer[] srcs, int offs, int len) Writes a sequence of bytes to this conduit from the given buffers.
int	writeFinal(ByteBuffer src) Writes some data to the conduit, with the same semantics as StreamSinkConduit.write(java.nio.ByteBuffer).
long	writeFinal(ByteBuffer[] srcs, int offset, int length) Writes some data to the conduit, with the same semantics as StreamSinkConduit.write(java.nio.ByteBuffer[], int, int).

Methods inherited from class java.lang.Object

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

Constructor Detail

NullStreamSinkConduit

public NullStreamSinkConduit(XnioIoThread writeThread)

Construct a new instance.

Parameters:

writeThread - the write thread for this conduit

Method Detail

transferFrom

public long transferFrom(FileChannel src,
                         long position,
                         long count)
                  throws IOException

Description copied from interface: StreamSinkConduit

Transfer bytes into this conduit from the given file.

Specified by:

transferFrom in interface StreamSinkConduit

Parameters:

src - the file to read from

position - the position within the file from which the transfer is to begin

count - the number of bytes to be transferred

Returns:

the number of bytes (possibly 0) that were actually transferred

Throws:

IOException - if an I/O error occurs

transferFrom

public long transferFrom(StreamSourceChannel source,
                         long count,
                         ByteBuffer throughBuffer)
                  throws IOException

Description copied from interface: StreamSinkConduit

Transfers bytes from the given channel source. On entry, throughBuffer will be cleared. On exit, the buffer will be flipped for emptying, and may be empty or may contain data. If this method returns a value less than count, then the remaining data in throughBuffer may contain data read from source which must be written to this channel to complete the operation.

Specified by:

transferFrom in interface StreamSinkConduit

Parameters:

source - the source to read from

count - the number of bytes to be transferred

throughBuffer - the buffer to copy through.

Returns:

the number of bytes (possibly 0) that were actually transferred, or -1 if the end of input was reached

Throws:

IOException - if an I/O error occurs

write

public int write(ByteBuffer src)
          throws IOException

Description copied from interface: StreamSinkConduit

Writes a sequence of bytes to this conduit from the given buffer.

Specified by:

write in interface StreamSinkConduit

Parameters:

src - the buffer containing data to write

Returns:

the number of bytes written, possibly 0

Throws:

ClosedChannelException - if this conduit's SinkConduit.terminateWrites() method was previously called

IOException - if an error occurs

write

public long write(ByteBuffer[] srcs,
                  int offs,
                  int len)
           throws IOException

Description copied from interface: StreamSinkConduit

Writes a sequence of bytes to this conduit from the given buffers.

Specified by:

write in interface StreamSinkConduit

Parameters:

srcs - the buffers containing data to write

offs - the offset into the buffer array

len - the number of buffers to write

Returns:

the number of bytes written, possibly 0

Throws:

ClosedChannelException - if this conduit's SinkConduit.terminateWrites() method was previously called

IOException - if an error occurs

writeFinal

public int writeFinal(ByteBuffer src)
               throws IOException

Description copied from interface: StreamSinkConduit

Writes some data to the conduit, with the same semantics as StreamSinkConduit.write(java.nio.ByteBuffer). If all the data is written out then the conduit will have its writes terminated. Semantically this method is equivalent to: int rem = src.remaining(); int written = conduit.write(src); if(written == rem) { conduit.terminateWrites() }

Specified by:

writeFinal in interface StreamSinkConduit

Parameters:

src - The data to write

Returns:

The amount of data that was actually written.

Throws:

IOException

writeFinal

public long writeFinal(ByteBuffer[] srcs,
                       int offset,
                       int length)
                throws IOException

Description copied from interface: StreamSinkConduit

Writes some data to the conduit, with the same semantics as StreamSinkConduit.write(java.nio.ByteBuffer[], int, int). If all the data is written out then the conduit will have its writes terminated.

Specified by:

writeFinal in interface StreamSinkConduit

Parameters:

srcs - The buffers from which bytes are to be retrieved

offset - The offset within the buffer array of the first buffer from which bytes are to be retrieved; must be non-negative and no larger than srcs.length

length - The maximum number of buffers to be accessed; must be non-negative and no larger than srcs.length - offset

Returns:

The amount of data that was actually written

Throws:

IOException

flush

public boolean flush()
              throws IOException

Description copied from interface: SinkConduit

Flush out any unwritten, buffered output.

Specified by:

flush in interface SinkConduit

Returns:

true if everything is flushed, false otherwise

Throws:

IOException - if flush fails

isWriteShutdown

public boolean isWriteShutdown()

Description copied from interface: SinkConduit

Determine whether writes have been fully shut down on this conduit.

Specified by:

isWriteShutdown in interface SinkConduit

Returns:

true if writes are fully shut down, false otherwise

suspendWrites

public void suspendWrites()

Description copied from interface: SinkConduit

Indicate that calling the conduit's WriteReadyHandler should be suspended.

Specified by:

suspendWrites in interface SinkConduit

resumeWrites

public void resumeWrites()

Description copied from interface: SinkConduit

Indicate that the conduit's WriteReadyHandler should be invoked as soon as data can be written without blocking.

Specified by:

resumeWrites in interface SinkConduit

wakeupWrites

public void wakeupWrites()

Description copied from interface: SinkConduit

Indicate that the conduit's WriteReadyHandler should be invoked immediately, and then again as soon as data can be written without blocking.

Specified by:

wakeupWrites in interface SinkConduit

isWriteResumed

public boolean isWriteResumed()

Description copied from interface: SinkConduit

Determine whether write notifications are currently enabled.

Specified by:

isWriteResumed in interface SinkConduit

Returns:

true if write notifications are enabled

awaitWritable

public void awaitWritable()
                   throws IOException

Description copied from interface: SinkConduit

Block until this channel becomes writable again. This method may return spuriously before the channel becomes writable.

Specified by:

awaitWritable in interface SinkConduit

Throws:

InterruptedIOException - if the operation is interrupted; the thread's interrupt flag will be set as well

IOException - if an I/O error occurs

awaitWritable

public void awaitWritable(long time,
                          TimeUnit timeUnit)
                   throws IOException

Description copied from interface: SinkConduit

Block until this conduit becomes writable again, or until the timeout expires. This method may return spuriously before the conduit becomes writable or the timeout expires.

Specified by:

awaitWritable in interface SinkConduit

Parameters:

time - the time to wait

timeUnit - the time unit

Throws:

InterruptedIOException - if the operation is interrupted; the thread's interrupt flag will be set as well

IOException - if an I/O error occurs

getWriteThread

public XnioIoThread getWriteThread()

Description copied from interface: SinkConduit

Get the write thread for this conduit.

Specified by:

getWriteThread in interface SinkConduit

Returns:

the thread, or null if none is configured or available

setWriteReadyHandler

public void setWriteReadyHandler(WriteReadyHandler handler)

Description copied from interface: SinkConduit

Set the handler which should receive readiness notifications. A filter may pass this invocation on to the filter it wraps, or it may substitute itself.

Specified by:

setWriteReadyHandler in interface SinkConduit

truncateWrites

public void truncateWrites()
                    throws IOException

Description copied from interface: SinkConduit

Terminate writes and discard any outstanding write data. The conduit is terminated and flushed regardless of the outcome of this method.

Specified by:

truncateWrites in interface SinkConduit

Throws:

IOException - if channel termination failed for some reason

terminateWrites

public void terminateWrites()
                     throws IOException

Description copied from interface: SinkConduit

Signal that no more write data is forthcoming. The conduit must be SinkConduit.flush()ed before it is considered to be shut down.

Specified by:

terminateWrites in interface SinkConduit

Throws:

IOException

getWorker

public XnioWorker getWorker()

Description copied from interface: Conduit

Get the XNIO worker associated with this conduit.

Specified by:

getWorker in interface Conduit

Returns:

the XNIO worker associated with this conduit