private void startReceiver() { if (receiver == null || !receiver.isAlive()) { receiver = new Thread(Util.getGlobalThreadGroup(), this, "ReceiverThread"); receiver.setDaemon(true); receiver.start(); if (log.isTraceEnabled()) log.trace("receiver thread started"); } }
public class TCPConnectionMap { private final Mapper mapper; private final InetAddress bind_addr; private final Address local_addr; // bind_addr + port of srv_sock private final ThreadGroup thread_group = new ThreadGroup(Util.getGlobalThreadGroup(), "ConnectionMap"); private final ServerSocket srv_sock; private Receiver receiver; private final long conn_expire_time; private final Log log = LogFactory.getLog(getClass()); private int recv_buf_size = 120000; private int send_buf_size = 60000; private int send_queue_size = 0; private int sock_conn_timeout = 1000; // max time in millis to wait for Socket.connect() to return private boolean tcp_nodelay = false; private int linger = -1; private final Thread acceptor; private final AtomicBoolean running = new AtomicBoolean(false); private volatile boolean use_send_queues = false; protected SocketFactory socket_factory = new DefaultSocketFactory(); public TCPConnectionMap( String service_name, ThreadFactory f, SocketFactory socket_factory, Receiver r, InetAddress bind_addr, InetAddress external_addr, int srv_port, int max_port) throws Exception { this(service_name, f, socket_factory, r, bind_addr, external_addr, srv_port, max_port, 0, 0); } public TCPConnectionMap( String service_name, ThreadFactory f, Receiver r, InetAddress bind_addr, InetAddress external_addr, int srv_port, int max_port, long reaper_interval, long conn_expire_time) throws Exception { this( service_name, f, null, r, bind_addr, external_addr, srv_port, max_port, reaper_interval, conn_expire_time); } public TCPConnectionMap( String service_name, ThreadFactory f, SocketFactory socket_factory, Receiver r, InetAddress bind_addr, InetAddress external_addr, int srv_port, int max_port, long reaper_interval, long conn_expire_time) throws Exception { this.mapper = new Mapper(f, reaper_interval); this.receiver = r; this.bind_addr = bind_addr; this.conn_expire_time = conn_expire_time; if (socket_factory != null) this.socket_factory = socket_factory; this.srv_sock = Util.createServerSocket(this.socket_factory, service_name, bind_addr, srv_port, max_port); if (external_addr != null) local_addr = new IpAddress(external_addr, srv_sock.getLocalPort()); else if (bind_addr != null) local_addr = new IpAddress(bind_addr, srv_sock.getLocalPort()); else local_addr = new IpAddress(srv_sock.getLocalPort()); acceptor = f.newThread(thread_group, new ConnectionAcceptor(), "ConnectionMap.Acceptor"); } public Address getLocalAddress() { return local_addr; } public Receiver getReceiver() { return receiver; } public void setReceiver(Receiver receiver) { this.receiver = receiver; } public SocketFactory getSocketFactory() { return socket_factory; } public void setSocketFactory(SocketFactory socket_factory) { this.socket_factory = socket_factory; } public void addConnectionMapListener( AbstractConnectionMap.ConnectionMapListener<TCPConnection> l) { mapper.addConnectionMapListener(l); } public void removeConnectionMapListener( AbstractConnectionMap.ConnectionMapListener<TCPConnection> l) { mapper.removeConnectionMapListener(l); } /** * Calls the receiver callback. We do not serialize access to this method, and it may be called * concurrently by several Connection handler threads. Therefore the receiver needs to be * reentrant. */ public void receive(Address sender, byte[] data, int offset, int length) { receiver.receive(sender, data, offset, length); } public void send(Address dest, byte[] data, int offset, int length) throws Exception { if (dest == null) { if (log.isErrorEnabled()) log.error("destination is null"); return; } if (data == null) { log.warn("data is null; discarding packet"); return; } if (!running.get()) { if (log.isDebugEnabled()) log.debug("connection table is not running, discarding message to " + dest); return; } if (dest.equals(local_addr)) { receive(local_addr, data, offset, length); return; } // 1. Try to obtain correct Connection (or create one if not yet existent) TCPConnection conn; conn = mapper.getConnection(dest); // 2. Send the message using that connection if (conn != null) { try { conn.send(data, offset, length); } catch (Exception ex) { mapper.removeConnection(dest); throw ex; } } } public void start() throws Exception { if (running.compareAndSet(false, true)) { acceptor.start(); mapper.start(); } } public void stop() { if (running.compareAndSet(true, false)) { try { getSocketFactory().close(srv_sock); } catch (IOException e) { } Util.interruptAndWaitToDie(acceptor); mapper.stop(); } } private void setSocketParameters(Socket client_sock) throws SocketException { if (log.isTraceEnabled()) log.trace( "[" + local_addr + "] accepted connection from " + client_sock.getInetAddress() + ":" + client_sock.getPort()); try { client_sock.setSendBufferSize(send_buf_size); } catch (IllegalArgumentException ex) { if (log.isErrorEnabled()) log.error("exception setting send buffer size to " + send_buf_size + " bytes", ex); } try { client_sock.setReceiveBufferSize(recv_buf_size); } catch (IllegalArgumentException ex) { if (log.isErrorEnabled()) log.error("exception setting receive buffer size to " + send_buf_size + " bytes", ex); } client_sock.setKeepAlive(true); client_sock.setTcpNoDelay(tcp_nodelay); if (linger > 0) client_sock.setSoLinger(true, linger); else client_sock.setSoLinger(false, -1); } /** Used for message reception. */ public interface Receiver { void receive(Address sender, byte[] data, int offset, int length); } private class ConnectionAcceptor implements Runnable { /** * Acceptor thread. Continuously accept new connections. Create a new thread for each new * connection and put it in conns. When the thread should stop, it is interrupted by the thread * creator. */ public void run() { while (!srv_sock.isClosed() && !Thread.currentThread().isInterrupted()) { TCPConnection conn = null; Socket client_sock = null; try { client_sock = srv_sock.accept(); conn = new TCPConnection(client_sock); Address peer_addr = conn.getPeerAddress(); mapper.getLock().lock(); try { boolean currentConnectionOpen = mapper.hasOpenConnection(peer_addr); boolean replaceWithNewConnection = false; if (currentConnectionOpen) { replaceWithNewConnection = peer_addr.compareTo(local_addr) > 0; } if (!currentConnectionOpen || replaceWithNewConnection) { mapper.removeConnection(peer_addr); mapper.addConnection(peer_addr, conn); conn.start(mapper.getThreadFactory()); // starts handler thread on this socket } else { Util.close(conn); } } finally { mapper.getLock().unlock(); } } catch (SocketException se) { boolean threadExiting = srv_sock.isClosed() || Thread.currentThread().isInterrupted(); if (threadExiting) { break; } else { if (log.isWarnEnabled()) log.warn("Could not accept connection from peer ", se); Util.close(conn); Util.close(client_sock); } } catch (Exception ex) { if (log.isWarnEnabled()) log.warn("Could not read accept connection from peer " + ex); Util.close(conn); Util.close(client_sock); } } if (log.isTraceEnabled()) log.trace(Thread.currentThread().getName() + " terminated"); } } public void setReceiveBufferSize(int recv_buf_size) { this.recv_buf_size = recv_buf_size; } public void setSocketConnectionTimeout(int sock_conn_timeout) { this.sock_conn_timeout = sock_conn_timeout; } public void setSendBufferSize(int send_buf_size) { this.send_buf_size = send_buf_size; } public void setLinger(int linger) { this.linger = linger; } public void setTcpNodelay(boolean tcp_nodelay) { this.tcp_nodelay = tcp_nodelay; } public void setSendQueueSize(int send_queue_size) { this.send_queue_size = send_queue_size; } public void setUseSendQueues(boolean use_send_queues) { this.use_send_queues = use_send_queues; } public int getNumConnections() { return mapper.getNumConnections(); } public boolean connectionEstablishedTo(Address addr) { return mapper.connectionEstablishedTo(addr); } public String printConnections() { return mapper.printConnections(); } public void retainAll(Collection<Address> members) { mapper.retainAll(members); } public long getConnectionExpiryTimeout() { return conn_expire_time; } public int getSenderQueueSize() { return send_queue_size; } public String toString() { StringBuilder ret = new StringBuilder(); ret.append("local_addr=" + local_addr).append("\n"); ret.append("connections (" + mapper.size() + "):\n"); ret.append(mapper.toString()); ret.append('\n'); return ret.toString(); } public class TCPConnection implements Connection { private final Socket sock; // socket to/from peer (result of srv_sock.accept() or new Socket()) private final Lock send_lock = new ReentrantLock(); // serialize send() private final Log log = LogFactory.getLog(getClass()); private final byte[] cookie = {'b', 'e', 'l', 'a'}; private final DataOutputStream out; private final DataInputStream in; private final Address peer_addr; // address of the 'other end' of the connection private final int peer_addr_read_timeout = 2000; // max time in milliseconds to block on reading peer address private long last_access = System.currentTimeMillis(); // last time a message was sent or received private Sender sender; private ConnectionPeerReceiver connectionPeerReceiver; private AtomicBoolean active = new AtomicBoolean(false); TCPConnection(Address peer_addr) throws Exception { if (peer_addr == null) throw new IllegalArgumentException("Invalid parameter peer_addr=" + peer_addr); SocketAddress destAddr = new InetSocketAddress( ((IpAddress) peer_addr).getIpAddress(), ((IpAddress) peer_addr).getPort()); this.sock = new Socket(); this.sock.bind(new InetSocketAddress(bind_addr, 0)); Util.connect(this.sock, destAddr, sock_conn_timeout); setSocketParameters(sock); this.out = new DataOutputStream(new BufferedOutputStream(sock.getOutputStream())); this.in = new DataInputStream(new BufferedInputStream(sock.getInputStream())); sendLocalAddress(getLocalAddress()); this.peer_addr = peer_addr; } TCPConnection(Socket s) throws Exception { if (s == null) throw new IllegalArgumentException("Invalid parameter s=" + s); setSocketParameters(s); this.out = new DataOutputStream(new BufferedOutputStream(s.getOutputStream())); this.in = new DataInputStream(new BufferedInputStream(s.getInputStream())); this.peer_addr = readPeerAddress(s); this.sock = s; } private Address getPeerAddress() { return peer_addr; } private void updateLastAccessed() { last_access = System.currentTimeMillis(); } private void start(ThreadFactory f) { // only start once.... if (active.compareAndSet(false, true)) { connectionPeerReceiver = new ConnectionPeerReceiver(f); connectionPeerReceiver.start(); if (isSenderUsed()) { sender = new Sender(f, getSenderQueueSize()); sender.start(); } } } private boolean isSenderUsed() { return getSenderQueueSize() > 0 && use_send_queues; } private String getSockAddress() { StringBuilder sb = new StringBuilder(); if (sock != null) { sb.append(sock.getLocalAddress().getHostAddress()).append(':').append(sock.getLocalPort()); sb.append(" - ") .append(sock.getInetAddress().getHostAddress()) .append(':') .append(sock.getPort()); } return sb.toString(); } /** * @param data Guaranteed to be non null * @param offset * @param length */ private void send(byte[] data, int offset, int length) throws Exception { if (isSenderUsed()) { // we need to copy the byte[] buffer here because the original buffer might get // changed meanwhile byte[] tmp = new byte[length]; System.arraycopy(data, offset, tmp, 0, length); sender.addToQueue(tmp); } else { _send(data, offset, length, true); } } /** * Sends data using the 'out' output stream of the socket * * @param data * @param offset * @param length * @param acquire_lock * @throws Exception */ private void _send(byte[] data, int offset, int length, boolean acquire_lock) throws Exception { if (acquire_lock) send_lock.lock(); try { doSend(data, offset, length); updateLastAccessed(); } catch (InterruptedException iex) { Thread.currentThread().interrupt(); // set interrupt flag again } finally { if (acquire_lock) send_lock.unlock(); } } private void doSend(byte[] data, int offset, int length) throws Exception { // we're using 'double-writes', sending the buffer to the destination in 2 pieces. this would // ensure that, if the peer closed the connection while we were idle, we would get an // exception. // this won't happen if we use a single write (see Stevens, ch. 5.13). out.writeInt(length); // write the length of the data buffer first Util.doubleWrite(data, offset, length, out); out.flush(); // may not be very efficient (but safe) } /** * Reads the peer's address. First a cookie has to be sent which has to match my own cookie, * otherwise the connection will be refused */ private Address readPeerAddress(Socket client_sock) throws Exception { int timeout = client_sock.getSoTimeout(); client_sock.setSoTimeout(peer_addr_read_timeout); try { // read the cookie first byte[] input_cookie = new byte[cookie.length]; in.readFully(input_cookie, 0, input_cookie.length); if (!matchCookie(input_cookie)) throw new SocketException( "ConnectionMap.Connection.readPeerAddress(): cookie read by " + getLocalAddress() + " does not match own cookie; terminating connection"); // then read the version short version = in.readShort(); if (!Version.isBinaryCompatible(version)) { if (log.isWarnEnabled()) log.warn( new StringBuilder("packet from ") .append(client_sock.getInetAddress()) .append(':') .append(client_sock.getPort()) .append(" has different version (") .append(Version.print(version)) .append(") from ours (") .append(Version.printVersion()) .append("). This may cause problems") .toString()); } Address client_peer_addr = new IpAddress(); client_peer_addr.readFrom(in); updateLastAccessed(); return client_peer_addr; } finally { client_sock.setSoTimeout(timeout); } } /** * Send the cookie first, then the our port number. If the cookie doesn't match the receiver's * cookie, the receiver will reject the connection and close it. * * @throws IOException */ private void sendLocalAddress(Address local_addr) throws IOException { // write the cookie out.write(cookie, 0, cookie.length); // write the version out.writeShort(Version.version); local_addr.writeTo(out); out.flush(); // needed ? updateLastAccessed(); } private boolean matchCookie(byte[] input) { if (input == null || input.length < cookie.length) return false; for (int i = 0; i < cookie.length; i++) if (cookie[i] != input[i]) return false; return true; } private class ConnectionPeerReceiver implements Runnable { private Thread recv; private final AtomicBoolean receiving = new AtomicBoolean(false); public ConnectionPeerReceiver(ThreadFactory f) { recv = f.newThread(this, "Connection.Receiver [" + getSockAddress() + "]"); } public void start() { if (receiving.compareAndSet(false, true)) { recv.start(); } } public void stop() { if (receiving.compareAndSet(true, false)) { recv.interrupt(); } } public boolean isRunning() { return receiving.get(); } public boolean canRun() { return isRunning() && isConnected(); } public void run() { try { while (!Thread.currentThread().isInterrupted() && canRun()) { try { int len = in.readInt(); byte[] buf = new byte[len]; in.readFully(buf, 0, len); updateLastAccessed(); receiver.receive(peer_addr, buf, 0, len); } catch (OutOfMemoryError mem_ex) { break; // continue; } catch (IOException io_ex) { break; } catch (Throwable e) { } } } finally { Util.close(TCPConnection.this); } } } private class Sender implements Runnable { final BlockingQueue<byte[]> send_queue; final Thread runner; private final AtomicBoolean running = new AtomicBoolean(false); public Sender(ThreadFactory tf, int send_queue_size) { this.runner = tf.newThread(this, "Connection.Sender [" + getSockAddress() + "]"); this.send_queue = new LinkedBlockingQueue<byte[]>(send_queue_size); } public void addToQueue(byte[] data) throws Exception { if (canRun()) send_queue.add(data); } public void start() { if (running.compareAndSet(false, true)) { runner.start(); } } public void stop() { if (running.compareAndSet(true, false)) { runner.interrupt(); } } public boolean isRunning() { return running.get(); } public boolean canRun() { return isRunning() && isConnected(); } public void run() { try { while (!Thread.currentThread().isInterrupted() && canRun()) { byte[] data = null; try { data = send_queue.take(); } catch (InterruptedException e) { // Thread.currentThread().interrupt(); break; } if (data != null) { try { _send(data, 0, data.length, false); } catch (Throwable ignored) { } } } } finally { Util.close(TCPConnection.this); } if (log.isTraceEnabled()) log.trace("TCPConnection.Sender thread terminated at " + local_addr); } } public String toString() { StringBuilder ret = new StringBuilder(); InetAddress local = null, remote = null; String local_str, remote_str; Socket tmp_sock = sock; if (tmp_sock == null) ret.append("<null socket>"); else { // since the sock variable gets set to null we want to make // make sure we make it through here without a nullpointer exception local = tmp_sock.getLocalAddress(); remote = tmp_sock.getInetAddress(); local_str = local != null ? Util.shortName(local) : "<null>"; remote_str = remote != null ? Util.shortName(remote) : "<null>"; ret.append( '<' + local_str + ':' + tmp_sock.getLocalPort() + " --> " + remote_str + ':' + tmp_sock.getPort() + "> (" + ((System.currentTimeMillis() - last_access) / 1000) + " secs old)"); } tmp_sock = null; return ret.toString(); } public boolean isExpired(long now) { return getConnectionExpiryTimeout() > 0 && now - last_access >= getConnectionExpiryTimeout(); } public boolean isConnected() { return !sock.isClosed() && sock.isConnected(); } public boolean isOpen() { return isConnected() && (!isSenderUsed() || sender.isRunning()) && (connectionPeerReceiver != null && connectionPeerReceiver.isRunning()); } public void close() throws IOException { // can close even if start was never called... send_lock.lock(); try { connectionPeerReceiver.stop(); if (isSenderUsed()) { sender.stop(); } Util.close(sock); Util.close(out); Util.close(in); } finally { send_lock.unlock(); } mapper.notifyConnectionClosed(peer_addr); } } private class Mapper extends AbstractConnectionMap<TCPConnection> { public Mapper(ThreadFactory factory) { super(factory); } public Mapper(ThreadFactory factory, long reaper_interval) { super(factory, reaper_interval); } public TCPConnection getConnection(Address dest) throws Exception { TCPConnection conn = null; getLock().lock(); try { conn = conns.get(dest); if (conn != null && conn.isOpen()) return conn; try { conn = new TCPConnection(dest); conn.start(getThreadFactory()); addConnection(dest, conn); if (log.isTraceEnabled()) log.trace("created socket to " + dest); } catch (Exception ex) { if (log.isTraceEnabled()) log.trace("failed creating connection to " + dest); } } finally { getLock().unlock(); } return conn; } public boolean connectionEstablishedTo(Address address) { lock.lock(); try { TCPConnection conn = conns.get(address); return conn != null && conn.isConnected(); } finally { lock.unlock(); } } public int size() { return conns.size(); } public String toString() { StringBuilder sb = new StringBuilder(); getLock().lock(); try { for (Map.Entry<Address, TCPConnection> entry : conns.entrySet()) { sb.append(entry.getKey()).append(": ").append(entry.getValue()).append("\n"); } return sb.toString(); } finally { getLock().unlock(); } } } }