private void writeHeaders(
StompHeaderAccessor headers, Message<byte[]> message, DataOutputStream output)
throws IOException {
Map<String, List<String>> stompHeaders = headers.toStompHeaderMap();
if (SimpMessageType.HEARTBEAT.equals(headers.getMessageType())) {
logger.trace("Encoded heartbeat");
} else if (logger.isDebugEnabled()) {
logger.debug("Encoded STOMP command=" + headers.getCommand() + " headers=" + stompHeaders);
}
for (Entry<String, List<String>> entry : stompHeaders.entrySet()) {
byte[] key = getUtf8BytesEscapingIfNecessary(entry.getKey(), headers);
for (String value : entry.getValue()) {
output.write(key);
output.write(COLON);
output.write(getUtf8BytesEscapingIfNecessary(value, headers));
output.write(LF);
}
}
if ((headers.getCommand() == StompCommand.SEND)
|| (headers.getCommand() == StompCommand.MESSAGE)
|| (headers.getCommand() == StompCommand.ERROR)) {
output.write("content-length:".getBytes(UTF8_CHARSET));
output.write(Integer.toString(message.getPayload().length).getBytes(UTF8_CHARSET));
output.write(LF);
}
}
/**
* Encodes the given payload and headers into a {@code byte[]}.
*
* @param headers the headers
* @param payload the payload
* @return the encoded message
*/
public byte[] encode(Map<String, Object> headers, byte[] payload) {
Assert.notNull(headers, "'headers' is required");
Assert.notNull(payload, "'payload' is required");
try {
ByteArrayOutputStream baos = new ByteArrayOutputStream(128 + payload.length);
DataOutputStream output = new DataOutputStream(baos);
if (SimpMessageType.HEARTBEAT.equals(SimpMessageHeaderAccessor.getMessageType(headers))) {
logger.trace("Encoded heartbeat");
output.write(StompDecoder.HEARTBEAT_PAYLOAD);
} else {
StompCommand command = StompHeaderAccessor.getCommand(headers);
Assert.notNull(command, "Missing STOMP command: " + headers);
output.write(command.toString().getBytes(StompDecoder.UTF8_CHARSET));
output.write(LF);
writeHeaders(command, headers, payload, output);
output.write(LF);
writeBody(payload, output);
output.write((byte) 0);
}
return baos.toByteArray();
} catch (IOException e) {
throw new StompConversionException(
"Failed to encode STOMP frame, headers=" + headers + ".", e);
}
}