Package com.swiftmq.net.protocol

Class ProtocolOutputHandler

java.lang.Object

java.io.OutputStream

com.swiftmq.net.protocol.ProtocolOutputHandler

All Implemented Interfaces:

Closeable, Flushable, AutoCloseable

Direct Known Subclasses:

RawOutputHandler, SMQPOutputHandler

public abstract class ProtocolOutputHandler
extends OutputStream

A ProtocolOutputHandler is the complement to a ProtocolInputHandler and responsible for protocol specific packaging before data is sent to the network. The ProtocolOutputHandler is an OutputStream and will be used as such from the Swiftlets. These just write to the OutputStream and call flush() at the end which leads to a call to markChunkCompleted() and then to an invocation of an registered OutputListener which performs the write to the network. This could be done either blocking or non-blocking. The OutputListener returns the number of bytes written to the network and the invocation continues until all bytes have been written.

Author:

IIT GmbH, Bremen/Germany, Copyright (c) 2000-2002, All Rights Reserved

Constructor Summary

Constructors

Constructor	Description
ProtocolOutputHandler()

Method Summary

Modifier and Type	Method	Description
protected abstract void	addByte(byte b)	Add a byte to the current chunk.
protected abstract void	addBytes(byte[] b, int offset, int len)	Adds a number of bytes to the current chunk.
abstract ProtocolOutputHandler	create(int bufferSize, int extendSize)	Factory method to create a new ProtocolOutputHandler.
void	flush()
protected abstract byte[]	getByteArray()	Returns a reference to the byte array of the current chunk to transmit.
abstract int	getChunkCount()	Returns the number of chunk the handler has stored.
protected abstract int	getLength()	Returns the number of bytes to transmit, starting at the offset.
protected abstract int	getOffset()	Returns the offset in the byte array of the current chunk where transmit should start.
final void	invokeOutputListener()	Invokes the OutputListener.
protected abstract void	markChunkCompleted()	Marks a chunk completed.
protected abstract void	setBytesWritten(int written)	Sets the number of bytes written from the OutputListener.
final void	setOutputListener(OutputListener listener)	Set the OutputListener.
void	write(byte[] b, int offset, int len)
void	write(int b)

Methods inherited from class java.io.OutputStream

close, nullOutputStream, write

Methods inherited from class java.lang.Object

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

Constructor Details

ProtocolOutputHandler

public ProtocolOutputHandler()

Method Details

setOutputListener

public final void setOutputListener(OutputListener listener)

Set the OutputListener. The OutputListener is implemented by the Network Swiftlet.

Parameters:

listener - listenr.

invokeOutputListener

public final void invokeOutputListener()
                                throws IOException

Invokes the OutputListener. Done by the Netwok Swiftlet.

Throws:

IOException - on error.

write

public void write(int b)
           throws IOException

Specified by:

write in class OutputStream

Throws:

IOException

write

public void write(byte[] b,
 int offset,
 int len)
           throws IOException

Overrides:

write in class OutputStream

Throws:

IOException

flush

public void flush()
           throws IOException

Specified by:

flush in interface Flushable

Overrides:

flush in class OutputStream

Throws:

IOException

create

public abstract ProtocolOutputHandler create(int bufferSize,
 int extendSize)

Factory method to create a new ProtocolOutputHandler. For example, a RawOutputHandler returns a RawOutputHandler here.

Parameters:

bufferSize - initial buffer size

extendSize - extend size

Returns:

new protocol input handler.

getChunkCount

public abstract int getChunkCount()

Returns the number of chunk the handler has stored.

Returns:

number of chunks.

markChunkCompleted

protected abstract void markChunkCompleted()

Marks a chunk completed. Called during flush() If a protocol transmits byte streams with a length field in front, this is the place to determine the length.

getByteArray

protected abstract byte[] getByteArray()

Returns a reference to the byte array of the current chunk to transmit. Called during invokeOutputListener().

Returns:

byte array.

getOffset

protected abstract int getOffset()

Returns the offset in the byte array of the current chunk where transmit should start. Called during invokeOutputListener().

Returns:

offset.

getLength

protected abstract int getLength()

Returns the number of bytes to transmit, starting at the offset. Called during invokeOutputListener().

Returns:

length.

setBytesWritten

protected abstract void setBytesWritten(int written)

Sets the number of bytes written from the OutputListener. This is the actual number of bytes written from the OutputListener to the network. The offset then must be set to offset+written and the length to length-written. If all bytes of the current chunk have been written, the chunk can be destroyed or marked for reuse.

Parameters:

written - number of written bytes.

addByte

protected abstract void addByte(byte b)

Add a byte to the current chunk. Called from write(b).

Parameters:

b - byte.

addBytes

protected abstract void addBytes(byte[] b,
 int offset,
 int len)

Adds a number of bytes to the current chunk. Called from write(b[],offset,len).

Parameters:

b - byte array.

offset - offset.

len - length.