@Override
public List<MessagePart> sendMessagePart(List<MessagePart> uncompressedParts) {
List<MessagePart> allCompressedParts = new ArrayList<MessagePart>();
for (MessagePart uncompressedPart : uncompressedParts) {
byte opCode = uncompressedPart.getOpCode();
if (Util.isControl(opCode)) {
// Control messages can appear in the middle of other messages
// and must not be compressed. Pass it straight through
allCompressedParts.add(uncompressedPart);
} else {
List<MessagePart> compressedParts = new ArrayList<MessagePart>();
ByteBuffer uncompressedPayload = uncompressedPart.getPayload();
SendHandler uncompressedIntermediateHandler = uncompressedPart.getIntermediateHandler();
deflater.setInput(
uncompressedPayload.array(),
uncompressedPayload.arrayOffset() + uncompressedPayload.position(),
uncompressedPayload.remaining());
int flush = (uncompressedPart.isFin() ? Deflater.SYNC_FLUSH : Deflater.NO_FLUSH);
boolean deflateRequired = true;
while (deflateRequired) {
ByteBuffer compressedPayload = writeBuffer;
int written =
deflater.deflate(
compressedPayload.array(),
compressedPayload.arrayOffset() + compressedPayload.position(),
compressedPayload.remaining(),
flush);
compressedPayload.position(compressedPayload.position() + written);
if (!uncompressedPart.isFin()
&& compressedPayload.hasRemaining()
&& deflater.needsInput()) {
// This message part has been fully processed by the
// deflater. Fire the send handler for this message part
// and move on to the next message part.
break;
}
// If this point is reached, a new compressed message part
// will be created...
MessagePart compressedPart;
// .. and a new writeBuffer will be required.
writeBuffer = ByteBuffer.allocate(Constants.DEFAULT_BUFFER_SIZE);
// Flip the compressed payload ready for writing
compressedPayload.flip();
boolean fin = uncompressedPart.isFin();
boolean full = compressedPayload.limit() == compressedPayload.capacity();
boolean needsInput = deflater.needsInput();
if (fin && !full && needsInput) {
// End of compressed message. Drop EOM bytes and output.
compressedPayload.limit(compressedPayload.limit() - EOM_BYTES.length);
compressedPart =
new MessagePart(
true,
getRsv(uncompressedPart),
opCode,
compressedPayload,
uncompressedIntermediateHandler,
uncompressedIntermediateHandler);
deflateRequired = false;
startNewMessage();
} else if (full && !needsInput) {
// Write buffer full and input message not fully read.
// Output and start new compressed part.
compressedPart =
new MessagePart(
false,
getRsv(uncompressedPart),
opCode,
compressedPayload,
uncompressedIntermediateHandler,
uncompressedIntermediateHandler);
} else if (!fin && full && needsInput) {
// Write buffer full and input message not fully read.
// Output and get more data.
compressedPart =
new MessagePart(
false,
getRsv(uncompressedPart),
opCode,
compressedPayload,
uncompressedIntermediateHandler,
uncompressedIntermediateHandler);
deflateRequired = false;
} else if (fin && full && needsInput) {
// Write buffer full. Input fully read. Deflater may be
// in one of four states:
// - output complete (just happened to align with end of
// buffer
// - in middle of EOM bytes
// - about to write EOM bytes
// - more data to write
int eomBufferWritten =
deflater.deflate(EOM_BUFFER, 0, EOM_BUFFER.length, Deflater.SYNC_FLUSH);
if (eomBufferWritten < EOM_BUFFER.length) {
// EOM has just been completed
compressedPayload.limit(
compressedPayload.limit() - EOM_BYTES.length + eomBufferWritten);
compressedPart =
new MessagePart(
true,
getRsv(uncompressedPart),
opCode,
compressedPayload,
uncompressedIntermediateHandler,
uncompressedIntermediateHandler);
deflateRequired = false;
startNewMessage();
} else {
// More data to write
// Copy bytes to new write buffer
writeBuffer.put(EOM_BUFFER, 0, eomBufferWritten);
compressedPart =
new MessagePart(
false,
getRsv(uncompressedPart),
opCode,
compressedPayload,
uncompressedIntermediateHandler,
uncompressedIntermediateHandler);
}
} else {
throw new IllegalStateException("Should never happen");
}
// Add the newly created compressed part to the set of parts
// to pass on to the next transformation.
compressedParts.add(compressedPart);
}
SendHandler uncompressedEndHandler = uncompressedPart.getEndHandler();
int size = compressedParts.size();
if (size > 0) {
compressedParts.get(size - 1).setEndHandler(uncompressedEndHandler);
}
allCompressedParts.addAll(compressedParts);
}
}
if (next == null) {
return allCompressedParts;
} else {
return next.sendMessagePart(allCompressedParts);
}
}
