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| public class WebSocket {
private final ServerSocket serverSocket = new ServerSocket(8081);
@PreDestroy
public void destroy() throws IOException {
serverSocket.close();
}
public static void main(String[] args) throws IOException {
WebSocket webSocket = new WebSocket();
}
public WebSocket() throws IOException {
while (true) {
Socket socket = serverSocket.accept();
OutputStream outputStream = socket.getOutputStream();
InputStream inputStream = socket.getInputStream();
Inflater inflater = new Inflater(true);
Deflater deflater = new Deflater(Deflater.DEFAULT_COMPRESSION, true);
new Thread(() -> {
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
new Thread(() -> {
try {
byte[] bytes = new byte[1024];
int read;
while (-1 != (read = inputStream.read(bytes))) {
byteArrayOutputStream.write(bytes, 0, read);
}
} catch (IOException e) {
throw new RuntimeException(e);
}
}).start();
try {
boolean first = true;
while (true) {
ThreadUtil.sleep(10);
if (byteArrayOutputStream.size() < 1) {
continue;
}
byte[] bytes = byteArrayOutputStream.toByteArray();
byteArrayOutputStream.reset();
if (first) {
String request = new String(bytes);
System.out.println(request);
Map<String, String> headers = getHeaders(request);
String secWebsocketKey = headers.get("Sec-WebSocket-Key");
String secWebsocketAccept = calculateWebSocketAccept(secWebsocketKey);
String response = "HTTP/1.1 101 \r\n" +
"Connection: upgrade\r\n" +
"Upgrade: websocket\r\n" +
"Sec-WebSocket-Accept: " + secWebsocketAccept + "\r\n" +
"Sec-WebSocket-Extensions: permessage-deflate;client_max_window_bits=15\r\n" +
"\r\n";
IoUtil.write(outputStream, CharsetUtil.UTF_8, false, response);
first = false;
} else {
if (isMask(bytes)) {
int payloadLength = getPayloadLength(bytes);
byte[] unMaskPayload = getUnMaskPayload(bytes, payloadLength);
System.out.println(new String(decompressData(inflater, unMaskPayload, 0, payloadLength)));
}
String message = "hello";
byte[] compressData = compressData(deflater, message.getBytes());
byte[] data = createData(compressData.length, compressData);
IoUtil.write(outputStream, false, data);
}
}
} catch (NoSuchAlgorithmException e) {
throw new RuntimeException(e);
}
}).start();
}
}
public static String calculateWebSocketAccept(String webSocketKey) throws NoSuchAlgorithmException {
String magicString = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
String concatenated = webSocketKey + magicString;
MessageDigest digest = MessageDigest.getInstance("SHA-1");
byte[] hashedBytes = digest.digest(concatenated.getBytes(StandardCharsets.UTF_8));
return Base64.getEncoder().encodeToString(hashedBytes);
}
public static Map<String, String> getHeaders(String request) {
Map<String, String> map = new HashMap<>();
String[] lines = request.split("\r\n");
for (int i = 1; i < lines.length; i++) {
String line = lines[i];
if (StringUtils.isBlank(line)) {
break;
}
String[] split = line.split(": ");
map.put(split[0], split[1]);
}
return map;
}
public static byte[] decompressData(Inflater inflater, byte[] input, int offset, int position) {
inflater.setInput(input, offset, position);
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
byte[] buffer = new byte[1024];
try {
while (!inflater.needsInput()){
int count = inflater.inflate(buffer);
outputStream.write(buffer, 0, count);
}
inflater.setInput(new byte[]{0, 0, -1, -1});
inflater.inflate(buffer);
} catch (DataFormatException e) {
e.printStackTrace();
}
return outputStream.toByteArray();
}
public boolean isMask(byte[] bytes) {
return (bytes[1] & 128) == 128;
}
public int getPayloadLength(byte[] bytes) {
int b = bytes[1] & 127;
if (b == 126) {
int result = 0;
for (int i = 2; i < 4; i++) {
result += (bytes[i] & 255) << (8 * (3 - i));
}
return result;
} else if (b == 127) {
int result = 0;
for (int i = 2; i < 10; i++) {
result += (bytes[i] & 255) << (8 * (9 - i));
}
return result;
} else {
return b;
}
}
public byte[] getUnMaskPayload(byte[] bytes, int payloadLength) {
int position = payloadLength > 65535 ? 10 : payloadLength > 125 ? 4 : 2;
byte[] maskingKeyBytes = ArrayUtil.sub(bytes, position, position + 4);
byte[] maskPayloadBytes = ArrayUtil.sub(bytes, position + 4, position + 4 + payloadLength);
byte[] payload = new byte[payloadLength];
for (int i = 0; i < payloadLength; i++) {
payload[i] = (byte) (maskPayloadBytes[i] ^ maskingKeyBytes[i % 4]);
}
return payload;
}
public static byte[] compressData(Deflater deflater, byte[] input) {
byte[] bytes = new byte[1024];
deflater.setInput(input);
int deflate = deflater.deflate(bytes, 0, bytes.length, Deflater.SYNC_FLUSH);
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
byteArrayOutputStream.write(bytes, 0, deflate - 4);
return byteArrayOutputStream.toByteArray();
}
public static byte[] createData(int payloadLength, byte[] maskData) {
byte[] one = new byte[]{(byte) 193};
byte[] two;
if (payloadLength > 65535) {
two = new byte[8];
two[0] = 127;
for (int i = 1; i < 9; i++) {
two[i] = (byte) (payloadLength & (8 * (9 - i)) >> (8 * (8 - i)));
}
} else if (payloadLength > 125) {
two = new byte[3];
two[0] = 126;
two[1] = (byte) (payloadLength >> 8);
two[2] = (byte) (payloadLength & 255);
} else {
two = new byte[]{(byte) payloadLength};
}
return ArrayUtil.addAll(one, two, maskData);
}
}
|
