@Override
protected int doWriteMessages(MessageBuf<Object> buf, boolean lastSpin) throws Exception {
DatagramPacket packet = (DatagramPacket) buf.peek();
ByteBuf data = packet.data();
int dataLen = data.readableBytes();
ByteBuffer nioData;
if (data.nioBufferCount() == 1) {
nioData = data.nioBuffer();
} else {
nioData = ByteBuffer.allocate(dataLen);
data.getBytes(data.readerIndex(), nioData);
nioData.flip();
}
final int writtenBytes = javaChannel().send(nioData, packet.remoteAddress());
final SelectionKey key = selectionKey();
final int interestOps = key.interestOps();
if (writtenBytes <= 0 && dataLen > 0) {
// Did not write a packet.
// 1) If 'lastSpin' is false, the caller will call this method again real soon.
// - Do not update OP_WRITE.
// 2) If 'lastSpin' is true, the caller will not retry.
// - Set OP_WRITE so that the event loop calls flushForcibly() later.
if (lastSpin) {
if ((interestOps & SelectionKey.OP_WRITE) == 0) {
key.interestOps(interestOps | SelectionKey.OP_WRITE);
}
}
return 0;
}
// Wrote a packet.
buf.remove();
// packet was written free up buffer
packet.free();
if (buf.isEmpty()) {
// Wrote the outbound buffer completely - clear OP_WRITE.
if ((interestOps & SelectionKey.OP_WRITE) != 0) {
key.interestOps(interestOps & ~SelectionKey.OP_WRITE);
}
}
return 1;
}
