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A very lightweight WebSocket client library for Java/Android which aims to implement the WebSocket protocol as defined in RFC 6455
The newest version!
package tech.gusavila92.websocketclient;
import tech.gusavila92.apache.commons.codec.binary.Base64;
import tech.gusavila92.apache.commons.codec.digest.DigestUtils;
import tech.gusavila92.apache.http.Header;
import tech.gusavila92.apache.http.HttpException;
import tech.gusavila92.apache.http.HttpResponse;
import tech.gusavila92.apache.http.StatusLine;
import tech.gusavila92.apache.http.impl.io.DefaultHttpResponseParser;
import tech.gusavila92.apache.http.impl.io.HttpTransportMetricsImpl;
import tech.gusavila92.apache.http.impl.io.SessionInputBufferImpl;
import tech.gusavila92.apache.http.io.HttpMessageParser;
import tech.gusavila92.websocketclient.common.Utils;
import tech.gusavila92.websocketclient.exceptions.UnknownOpcodeException;
import tech.gusavila92.websocketclient.exceptions.IllegalSchemeException;
import tech.gusavila92.websocketclient.exceptions.InvalidServerHandshakeException;
import tech.gusavila92.websocketclient.model.Payload;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.net.URI;
import java.nio.charset.Charset;
import java.security.SecureRandom;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.Map;
import java.util.Random;
import javax.net.SocketFactory;
import javax.net.ssl.SSLSocketFactory;
/**
* Implements the WebSocket protocol as defined in RFC 6455
*
* @author Gustavo Avila
*/
public abstract class WebSocketClient {
/**
* GUID used when processing Sec-WebSocket-Accept response header
*/
private static final String GUID = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
/**
* Denotes a continuation frame
*/
private static final int OPCODE_CONTINUATION = 0x0;
/**
* Denotes a UTF-8 encoded text frame
*/
private static final int OPCODE_TEXT = 0x1;
/**
* Denotes a binary frame
*/
private static final int OPCODE_BINARY = 0x2;
/**
* Denotes a close frame
*/
private static final int OPCODE_CLOSE = 0x8;
/**
* Denotes a Ping frame
*/
private static final int OPCODE_PING = 0x9;
/**
* Denotes a Pong frame
*/
private static final int OPCODE_PONG = 0xA;
/**
* Global lock for synchronized statements
*/
private final Object globalLock;
/**
* Connection URI
*/
private final URI uri;
/**
* Cryptographically secure random generator used for the masking key
*/
private final SecureRandom secureRandom;
/**
* Timeout in milliseconds to be used while the WebSocket is being connected
*/
private int connectTimeout;
/**
* Timeout in milliseconds for considering and idle connection as dead An
* idle connection is a connection that has not received data for a long
* time
*/
private int readTimeout;
/**
* Indicates if a connection must be reopened automatically due to an
* IOException
*/
private boolean automaticReconnection;
/**
* Time in milliseconds to wait before opening a new WebSocket connection
*/
private long waitTimeBeforeReconnection;
/**
* Indicates if the connect() method was called
*/
private volatile boolean isRunning;
/**
* Custom headers to be included into the handshake
*/
private Map headers;
/**
* Underlying WebSocket connection This instance could change due to an
* automatic reconnection Every time an automatic reconnection is fired,
* this reference changes
*/
private volatile WebSocketConnection webSocketConnection;
/**
* Thread used for reconnection intents
*/
private volatile Thread reconnectionThread;
private SSLSocketFactory socketFactory = (SSLSocketFactory) SSLSocketFactory.getDefault();
/**
* Initialize all the variables
*
* @param uri URI of the WebSocket server
*/
public WebSocketClient(URI uri) {
this.globalLock = new Object();
this.uri = uri;
this.secureRandom = new SecureRandom();
this.connectTimeout = 0;
this.readTimeout = 0;
this.automaticReconnection = false;
this.waitTimeBeforeReconnection = 0;
this.isRunning = false;
this.headers = new HashMap();
webSocketConnection = new WebSocketConnection();
}
public void setSSLSocketFactory(SSLSocketFactory sslSocketFactory) {
socketFactory = sslSocketFactory;
}
/**
* Called when the WebSocket handshake has been accepted and the WebSocket
* is ready to send and receive data
*/
public abstract void onOpen();
/**
* Called when a text message has been received
*
* @param message The UTF-8 encoded text received
*/
public abstract void onTextReceived(String message);
/**
* Called when a binary message has been received
*
* @param data The binary message received
*/
public abstract void onBinaryReceived(byte[] data);
/**
* Called when a ping message has been received
*
* @param data Optional data
*/
public abstract void onPingReceived(byte[] data);
/**
* Called when a pong message has been received
*
* @param data Optional data
*/
public abstract void onPongReceived(byte[] data);
/**
* Called when an exception has occurred
*
* @param e The exception that occurred
*/
public abstract void onException(Exception e);
/**
* Called when a close code has been received
*/
public abstract void onCloseReceived();
/**
* Adds a new header to the set of headers that will be send into the
* handshake This header will be added to the set of headers: Host, Upgrade,
* Connection, Sec-WebSocket-Key, Sec-WebSocket-Version
*
* @param key Name of the new header
* @param value Value of the new header
*/
public void addHeader(String key, String value) {
synchronized (globalLock) {
if (isRunning) {
throw new IllegalStateException("Cannot add header while WebSocketClient is running");
}
this.headers.put(key, value);
}
}
/**
* Set the timeout that will be used while the WebSocket is being connected
* If timeout expires before connecting, an IOException will be thrown
*
* @param connectTimeout Timeout in milliseconds
*/
public void setConnectTimeout(int connectTimeout) {
synchronized (globalLock) {
if (isRunning) {
throw new IllegalStateException("Cannot set connect timeout while WebSocketClient is running");
} else if (connectTimeout < 0) {
throw new IllegalStateException("Connect timeout must be greater or equal than zero");
}
this.connectTimeout = connectTimeout;
}
}
/**
* Sets the timeout for considering and idle connection as dead An idle
* connection is a connection that has not received data for a long time If
* timeout expires, an IOException will be thrown and you should consider
* opening a new WebSocket connection, or delegate this functionality to
* this WebSocketClient using the method setAutomaticReconnection(true)
*
* @param readTimeout Read timeout in milliseconds before considering an idle
* connection as dead
*/
public void setReadTimeout(int readTimeout) {
synchronized (globalLock) {
if (isRunning) {
throw new IllegalStateException("Cannot set read timeout while WebSocketClient is running");
} else if (readTimeout < 0) {
throw new IllegalStateException("Read timeout must be greater or equal than zero");
}
this.readTimeout = readTimeout;
}
}
/**
* Indicates that a connection must be reopened automatically due to an
* IOException. Every time a connection fails due to an IOException,
* onException() method is called before establishing a new connection. A
* connection will be reopened automatically if an IOException occurred, but
* other kinds of Exception will not reopen a connection
*
* @param waitTimeBeforeReconnection Wait time in milliseconds before trying to establish a new
* WebSocket connection. For performance reasons, you should set
* a wait time greater than zero
*/
public void enableAutomaticReconnection(long waitTimeBeforeReconnection) {
synchronized (globalLock) {
if (isRunning) {
throw new IllegalStateException(
"Cannot enable automatic reconnection while WebSocketClient is running");
} else if (waitTimeBeforeReconnection < 0) {
throw new IllegalStateException("Wait time between reconnections must be greater or equal than zero");
}
this.automaticReconnection = true;
this.waitTimeBeforeReconnection = waitTimeBeforeReconnection;
}
}
/**
* Indicates that a connection must not be reopened automatically due to an
* IOException
*/
public void disableAutomaticReconnection() {
synchronized (globalLock) {
if (isRunning) {
throw new IllegalStateException(
"Cannot disable automatic reconnection while WebSocketClient is running");
}
this.automaticReconnection = false;
}
}
/**
* Starts a new connection to the WebSocket server
*/
public void connect() {
synchronized (globalLock) {
if (isRunning) {
throw new IllegalStateException("WebSocketClient is not reusable");
}
this.isRunning = true;
createAndStartConnectionThread();
}
}
/**
* Creates and starts the thread that will handle the WebSocket connection
*/
private void createAndStartConnectionThread() {
new Thread(new Runnable() {
@Override
public void run() {
try {
boolean success = webSocketConnection.createAndConnectTCPSocket();
if (success) {
webSocketConnection.startConnection();
}
} catch (Exception e) {
synchronized (globalLock) {
if (isRunning) {
webSocketConnection.closeInternal();
onException(e);
if (e instanceof IOException && automaticReconnection) {
createAndStartReconnectionThread();
}
}
}
}
}
}).start();
}
/**
* Creates and starts the thread that will open a new WebSocket connection
*/
private void createAndStartReconnectionThread() {
reconnectionThread = new Thread(new Runnable() {
@Override
public void run() {
try {
Thread.sleep(waitTimeBeforeReconnection);
synchronized (globalLock) {
if (isRunning) {
webSocketConnection = new WebSocketConnection();
createAndStartConnectionThread();
}
}
} catch (InterruptedException e) {
// Expected behavior when the WebSocket connection is closed
}
}
});
reconnectionThread.start();
}
/**
* If the close method wasn't called, call onOpen method.
*/
private void notifyOnOpen() {
synchronized (globalLock) {
if (isRunning) {
onOpen();
}
}
}
/**
* If the close method wasn't called, call onTextReceived(String message)
* method.
*/
private void notifyOnTextReceived(String message) {
synchronized (globalLock) {
if (isRunning) {
onTextReceived(message);
}
}
}
/**
* If the close method wasn't called, call onBinaryReceived(byte[] data)
* method.
*/
private void notifyOnBinaryReceived(byte[] data) {
synchronized (globalLock) {
if (isRunning) {
onBinaryReceived(data);
}
}
}
/**
* If the close method wasn't called, call onPingReceived(byte[] data)
* method.
*/
private void notifyOnPingReceived(byte[] data) {
synchronized (globalLock) {
if (isRunning) {
onPingReceived(data);
}
}
}
/**
* If the close method wasn't called, call onPongReceived(byte[] data)
* method.
*/
private void notifyOnPongReceived(byte[] data) {
synchronized (globalLock) {
if (isRunning) {
onPongReceived(data);
}
}
}
/**
* If the close method wasn't called, call onException(Exception e) method.
*/
private void notifyOnException(Exception e) {
synchronized (globalLock) {
if (isRunning) {
onException(e);
}
}
}
/**
* If the close method wasn't called, call onCloseReceived() method.
*/
private void notifyOnCloseReceived() {
synchronized (globalLock) {
if (isRunning) {
onCloseReceived();
}
}
}
/**
* Sends a text message If the WebSocket is not connected yet, message will
* be send the next time the connection is opened
*
* @param message Message that will be send to the WebSocket server
*/
public void send(String message) {
byte[] data = message.getBytes(Charset.forName("UTF-8"));
final Payload payload = new Payload(OPCODE_TEXT, data);
new Thread(new Runnable() {
@Override
public void run() {
webSocketConnection.sendInternal(payload);
}
}).start();
}
/**
* Sends a binary message If the WebSocket is not connected yet, message
* will be send the next time the connection is opened
*
* @param data Binary data that will be send to the WebSocket server
*/
public void send(byte[] data) {
final Payload payload = new Payload(OPCODE_BINARY, data);
new Thread(new Runnable() {
@Override
public void run() {
webSocketConnection.sendInternal(payload);
}
}).start();
}
/**
* Sends a PING frame with an optional data.
*
* @param data Data to be sent, or null if there is no data.
*/
public void sendPing(byte[] data) {
final Payload payload = new Payload(OPCODE_PING, data);
new Thread(new Runnable() {
@Override
public void run() {
webSocketConnection.sendInternal(payload);
}
}).start();
}
/**
* Sends a PONG frame with an optional data.
*
* @param data Data to be sent, or null if there is no data.
*/
public void sendPong(byte[] data) {
final Payload payload = new Payload(OPCODE_PONG, data);
new Thread(new Runnable() {
@Override
public void run() {
webSocketConnection.sendInternal(payload);
}
}).start();
}
/**
* Closes the WebSocket connection
*/
public void close() {
new Thread(new Runnable() {
@Override
public void run() {
synchronized (globalLock) {
isRunning = false;
if (reconnectionThread != null) {
reconnectionThread.interrupt();
}
webSocketConnection.closeInternal();
}
}
}).start();
}
/**
* This represents an existing WebSocket connection
*
* @author Gustavo Avila
*/
private class WebSocketConnection {
/**
* Flag indicating if there are pending changes waiting to be read by
* the writer thread. It is used to avoid a missed signal between
* threads
*/
private volatile boolean pendingMessages;
/**
* Flag indicating if the closeInternal() method was called
*/
private volatile boolean isClosed;
/**
* Data waiting to be read from the writer thread
*/
private final LinkedList outBuffer;
/**
* This will act as a lock for synchronized statements
*/
private final Object internalLock;
/**
* Writer thread
*/
private final Thread writerThread;
/**
* TCP socket for the underlying WebSocket connection
*/
private Socket socket;
/**
* Socket input stream
*/
private BufferedInputStream bis;
/**
* Socket output stream
*/
private BufferedOutputStream bos;
/**
* Initialize the variables that will be used during a valid WebSocket
* connection
*/
private WebSocketConnection() {
this.pendingMessages = false;
this.isClosed = false;
this.outBuffer = new LinkedList();
this.internalLock = new Object();
this.writerThread = new Thread(new Runnable() {
@Override
public void run() {
synchronized (internalLock) {
while (true) {
if (!pendingMessages) {
try {
internalLock.wait();
} catch (InterruptedException e) {
// This should never happen
}
}
pendingMessages = false;
if (socket.isClosed()) {
return;
} else {
while (outBuffer.size() > 0) {
Payload payload = outBuffer.removeFirst();
int opcode = payload.getOpcode();
byte[] data = payload.getData();
try {
send(opcode, data);
} catch (IOException e) {
// Reader thread will notify this
// exception
// This thread just need to stop
return;
}
}
}
}
}
}
});
}
/**
* Creates and connects a TCP socket for the underlying connection
*
* @return true is the socket was successfully connected, false
* otherwise
* @throws IOException
*/
private boolean createAndConnectTCPSocket() throws IOException {
synchronized (internalLock) {
if (!isClosed) {
String scheme = uri.getScheme();
int port = uri.getPort();
if (scheme != null) {
if (scheme.equals("ws")) {
SocketFactory socketFactory = SocketFactory.getDefault();
socket = socketFactory.createSocket();
socket.setSoTimeout(readTimeout);
if (port != -1) {
socket.connect(new InetSocketAddress(uri.getHost(), port), connectTimeout);
} else {
socket.connect(new InetSocketAddress(uri.getHost(), 80), connectTimeout);
}
} else if (scheme.equals("wss")) {
socket = socketFactory.createSocket();
socket.setSoTimeout(readTimeout);
if (port != -1) {
socket.connect(new InetSocketAddress(uri.getHost(), port), connectTimeout);
} else {
socket.connect(new InetSocketAddress(uri.getHost(), 443), connectTimeout);
}
} else {
throw new IllegalSchemeException("The scheme component of the URI should be ws or wss");
}
} else {
throw new IllegalSchemeException("The scheme component of the URI cannot be null");
}
return true;
}
return false;
}
}
/**
* Starts the WebSocket connection
*
* @throws IOException
*/
private void startConnection() throws IOException {
bos = new BufferedOutputStream(socket.getOutputStream(), 65536);
byte[] key = new byte[16];
Random random = new Random();
random.nextBytes(key);
String base64Key = Base64.encodeBase64String(key);
byte[] handshake = createHandshake(base64Key);
bos.write(handshake);
bos.flush();
InputStream inputStream = socket.getInputStream();
verifyServerHandshake(inputStream, base64Key);
writerThread.start();
notifyOnOpen();
bis = new BufferedInputStream(socket.getInputStream(), 65536);
read();
}
/**
* Creates and returns a byte array containing the client handshake
*
* @param base64Key Random generated Sec-WebSocket-Key
* @return Byte array containing the client handshake
*/
private byte[] createHandshake(String base64Key) {
StringBuilder builder = new StringBuilder();
String path = uri.getRawPath();
String query = uri.getRawQuery();
String requestUri;
if (query == null) {
requestUri = path;
} else {
requestUri = path + "?" + query;
}
builder.append("GET " + requestUri + " HTTP/1.1");
builder.append("\r\n");
String host;
if (uri.getPort() == -1) {
host = uri.getHost();
} else {
host = uri.getHost() + ":" + uri.getPort();
}
builder.append("Host: " + host);
builder.append("\r\n");
builder.append("Upgrade: websocket");
builder.append("\r\n");
builder.append("Connection: Upgrade");
builder.append("\r\n");
builder.append("Sec-WebSocket-Key: " + base64Key);
builder.append("\r\n");
builder.append("Sec-WebSocket-Version: 13");
builder.append("\r\n");
for (Map.Entry entry : headers.entrySet()) {
builder.append(entry.getKey() + ": " + entry.getValue());
builder.append("\r\n");
}
builder.append("\r\n");
String handshake = builder.toString();
return handshake.getBytes(Charset.forName("ASCII"));
}
/**
* Verifies the validity of the server handshake
*
* @param inputStream Socket input stream
* @param secWebSocketKey Random generated Sec-WebSocket-Key
* @throws IOException
*/
private void verifyServerHandshake(InputStream inputStream, String secWebSocketKey) throws IOException {
try {
SessionInputBufferImpl sessionInputBuffer = new SessionInputBufferImpl(new HttpTransportMetricsImpl(),
8192);
sessionInputBuffer.bind(inputStream);
HttpMessageParser parser = new DefaultHttpResponseParser(sessionInputBuffer);
HttpResponse response = parser.parse();
StatusLine statusLine = response.getStatusLine();
if (statusLine == null) {
throw new InvalidServerHandshakeException("There is no status line");
}
int statusCode = statusLine.getStatusCode();
if (statusCode != 101) {
throw new InvalidServerHandshakeException(
"Invalid status code. Expected 101, received: " + statusCode);
}
Header[] upgradeHeader = response.getHeaders("Upgrade");
if (upgradeHeader.length == 0) {
throw new InvalidServerHandshakeException("There is no header named Upgrade");
}
String upgradeValue = upgradeHeader[0].getValue();
if (upgradeValue == null) {
throw new InvalidServerHandshakeException("There is no value for header Upgrade");
}
upgradeValue = upgradeValue.toLowerCase();
if (!upgradeValue.equals("websocket")) {
throw new InvalidServerHandshakeException(
"Invalid value for header Upgrade. Expected: websocket, received: " + upgradeValue);
}
Header[] connectionHeader = response.getHeaders("Connection");
if (connectionHeader.length == 0) {
throw new InvalidServerHandshakeException("There is no header named Connection");
}
String connectionValue = connectionHeader[0].getValue();
if (connectionValue == null) {
throw new InvalidServerHandshakeException("There is no value for header Connection");
}
connectionValue = connectionValue.toLowerCase();
if (!connectionValue.equals("upgrade")) {
throw new InvalidServerHandshakeException(
"Invalid value for header Connection. Expected: upgrade, received: " + connectionValue);
}
Header[] secWebSocketAcceptHeader = response.getHeaders("Sec-WebSocket-Accept");
if (secWebSocketAcceptHeader.length == 0) {
throw new InvalidServerHandshakeException("There is no header named Sec-WebSocket-Accept");
}
String secWebSocketAcceptValue = secWebSocketAcceptHeader[0].getValue();
if (secWebSocketAcceptValue == null) {
throw new InvalidServerHandshakeException("There is no value for header Sec-WebSocket-Accept");
}
String keyConcatenation = secWebSocketKey + GUID;
byte[] sha1 = DigestUtils.sha1(keyConcatenation);
String secWebSocketAccept = Base64.encodeBase64String(sha1);
if (!secWebSocketAcceptValue.equals(secWebSocketAccept)) {
throw new InvalidServerHandshakeException(
"Invalid value for header Sec-WebSocket-Accept. Expected: " + secWebSocketAccept
+ ", received: " + secWebSocketAcceptValue);
}
} catch (HttpException e) {
throw new InvalidServerHandshakeException(e.getMessage());
}
}
/**
* Sends a message to the WebSocket server
*
* @param opcode Message opcode
* @param payload Message payload
* @throws IOException
*/
private void send(int opcode, byte[] payload) throws IOException {
// The position of the data frame in which the next portion of code
// will start writing bytes
int nextPosition;
// The data frame
byte[] frame;
// The length of the payload data.
// If the payload is null, length will be 0.
int length = payload == null ? 0 : payload.length;
if (length < 126) {
// If payload length is less than 126,
// the frame must have the first two bytes, plus 4 bytes for the
// masking key
// plus the length of the payload
frame = new byte[6 + length];
// The first two bytes
frame[0] = (byte) (-128 | opcode);
frame[1] = (byte) (-128 | length);
// The masking key will start at position 2
nextPosition = 2;
} else if (length < 65536) {
// If payload length is greater than 126 and less than 65536,
// the frame must have the first two bytes, plus 2 bytes for the
// extended payload length,
// plus 4 bytes for the masking key, plus the length of the
// payload
frame = new byte[8 + length];
// The first two bytes
frame[0] = (byte) (-128 | opcode);
frame[1] = -2;
// Puts the length into the data frame
byte[] array = Utils.to2ByteArray(length);
frame[2] = array[0];
frame[3] = array[1];
// The masking key will start at position 4
nextPosition = 4;
} else {
// If payload length is greater or equal than 65536,
// the frame must have the first two bytes, plus 8 bytes for the
// extended payload length,
// plus 4 bytes for the masking key, plus the length of the
// payload
frame = new byte[14 + length];
// The first two bytes
frame[0] = (byte) (-128 | opcode);
frame[1] = -1;
// Puts the length into the data frame
byte[] array = Utils.to8ByteArray(length);
frame[2] = array[0];
frame[3] = array[1];
frame[4] = array[2];
frame[5] = array[3];
frame[6] = array[4];
frame[7] = array[5];
frame[8] = array[6];
frame[9] = array[7];
// The masking key will start at position 10
nextPosition = 10;
}
// Generate a random 4-byte masking key
byte[] mask = new byte[4];
secureRandom.nextBytes(mask);
// Puts the masking key into the data frame
frame[nextPosition] = mask[0];
frame[nextPosition + 1] = mask[1];
frame[nextPosition + 2] = mask[2];
frame[nextPosition + 3] = mask[3];
nextPosition += 4;
// Puts the masked payload data into the data frame
for (int i = 0; i < length; i++) {
frame[nextPosition] = ((byte) (payload[i] ^ mask[i % 4]));
nextPosition++;
}
// Sends the data frame
bos.write(frame);
bos.flush();
}
/**
* Listen for changes coming from the WebSocket server
*
* @throws IOException
*/
private void read() throws IOException {
// The first byte of every data frame
int firstByte;
// Loop until end of stream is reached.
while ((firstByte = bis.read()) != -1) {
// Data contained in the first byte
// int fin = (firstByte << 24) >>> 31;
// int rsv1 = (firstByte << 25) >>> 31;
// int rsv2 = (firstByte << 26) >>> 31;
// int rsv3 = (firstByte << 27) >>> 31;
int opcode = (firstByte << 28) >>> 28;
// Reads the second byte
int secondByte = bis.read();
// Data contained in the second byte
// int mask = (secondByte << 24) >>> 31;
int payloadLength = (secondByte << 25) >>> 25;
// If the length of payload data is less than 126, that's the
// final
// payload length
// Otherwise, it must be calculated as follows
if (payloadLength == 126) {
// Attempts to read the next 2 bytes
byte[] nextTwoBytes = new byte[2];
for (int i = 0; i < 2; i++) {
byte b = (byte) bis.read();
nextTwoBytes[i] = b;
}
// Those last 2 bytes will be interpreted as a 16-bit
// unsigned
// integer
byte[] integer = new byte[]{0, 0, nextTwoBytes[0], nextTwoBytes[1]};
payloadLength = Utils.fromByteArray(integer);
} else if (payloadLength == 127) {
// Attempts to read the next 8 bytes
byte[] nextEightBytes = new byte[8];
for (int i = 0; i < 8; i++) {
byte b = (byte) bis.read();
nextEightBytes[i] = b;
}
// Only the last 4 bytes matter because Java doesn't support
// arrays with more than 2^31 -1 elements, so a 64-bit
// unsigned
// integer cannot be processed
// Those last 4 bytes will be interpreted as a 32-bit
// unsigned
// integer
byte[] integer = new byte[]{nextEightBytes[4], nextEightBytes[5], nextEightBytes[6],
nextEightBytes[7]};
payloadLength = Utils.fromByteArray(integer);
}
// Attempts to read the payload data
byte[] data = new byte[payloadLength];
for (int i = 0; i < payloadLength; i++) {
byte b = (byte) bis.read();
data[i] = b;
}
// Execute the action depending on the opcode
switch (opcode) {
case OPCODE_CONTINUATION:
// Should be implemented
break;
case OPCODE_TEXT:
notifyOnTextReceived(new String(data, Charset.forName("UTF-8")));
break;
case OPCODE_BINARY:
notifyOnBinaryReceived(data);
break;
case OPCODE_CLOSE:
closeInternal();
notifyOnCloseReceived();
return;
case OPCODE_PING:
notifyOnPingReceived(data);
sendPong(data);
break;
case OPCODE_PONG:
notifyOnPongReceived(data);
break;
default:
closeInternal();
Exception e = new UnknownOpcodeException("Unknown opcode: 0x" + Integer.toHexString(opcode));
notifyOnException(e);
return;
}
}
// If there are not more data to be read,
// and if the connection didn't receive a close frame,
// an IOException must be thrown because the connection didn't close
// gracefully
throw new IOException("Unexpected end of stream");
}
/**
* Puts the payload into the out buffer and notifies the writer thread
* that new data is available
*
* @param payload Payload to be send to the WebSocket server
*/
private void sendInternal(Payload payload) {
synchronized (internalLock) {
outBuffer.addLast(payload);
pendingMessages = true;
internalLock.notify();
}
}
/**
* Closes the underlying WebSocket connection and notifies the writer
* thread and the reconnection thread that they must finish
*/
private void closeInternal() {
try {
synchronized (internalLock) {
if (!isClosed) {
isClosed = true;
if (socket != null) {
socket.close();
pendingMessages = true;
internalLock.notify();
}
}
}
} catch (IOException e) {
// This should never happen
}
}
}
}