Java DatagramChannel.open方法代碼示例

import java.nio.channels.DatagramChannel; //導入方法依賴的package包/類
/**
 * Create a new broadcaster
 *
 * @param address - multicast group address
 * @param srcAddress - address of interface we should use to broadcast.
 * @param port - udp port to use
 * @param ttl - packet ttl
 * @throws IOException
 */
public JdpBroadcaster(InetAddress address, InetAddress srcAddress, int port, int ttl)
        throws IOException, JdpException {
    this.addr = address;
    this.port = port;

    ProtocolFamily family = (address instanceof Inet6Address)
            ? StandardProtocolFamily.INET6 : StandardProtocolFamily.INET;

    channel = DatagramChannel.open(family);
    channel.setOption(StandardSocketOptions.SO_REUSEADDR, true);
    channel.setOption(StandardSocketOptions.IP_MULTICAST_TTL, ttl);

    // with srcAddress equal to null, this constructor do exactly the same as
    // if srcAddress is not passed
    if (srcAddress != null) {
        // User requests particular interface to bind to
        NetworkInterface interf = NetworkInterface.getByInetAddress(srcAddress);
        try {
            channel.bind(new InetSocketAddress(srcAddress, 0));
        } catch (UnsupportedAddressTypeException ex) {
            throw new JdpException("Unable to bind to source address");
        }
        channel.setOption(StandardSocketOptions.IP_MULTICAST_IF, interf);
    }
}
 

import java.nio.channels.DatagramChannel; //導入方法依賴的package包/類
public static void main(String[] args) throws IOException
{
    ByteBuffer data = ByteBuffer.wrap("TESTING DATA".getBytes());
    DatagramChannel dgChannel = DatagramChannel.open();

    for(int i = 0; i < targets.length; i++){
        data.rewind();
        SocketAddress sa = new InetSocketAddress(targets[i], port);
        System.out.println("-------------\nDG_Sending data:" +
                           "\n    remaining:" + data.remaining() +
                           "\n     position:" + data.position() +
                           "\n        limit:" + data.limit() +
                           "\n     capacity:" + data.capacity() +
                           " bytes on DG channel to " + sa);
        try {
            int n = dgChannel.send(data, sa);
            System.out.println("DG_Sent " + n + " bytes");
        } catch (IOException e) {
            //This regression test is to check vm crash only, so ioe is OK.
            e.printStackTrace();
        }
    }
    dgChannel.close();
}
 

import java.nio.channels.DatagramChannel; //導入方法依賴的package包/類
@Override
protected DatagramChannel newHandle(SocketAddress localAddress) throws Exception {
    DatagramChannel ch = DatagramChannel.open();

    try {
        if (localAddress != null) {
            ch.socket().bind(localAddress);
        }

        return ch;
    } catch (Exception e) {
        // If we got an exception while binding the datagram,
        // we have to close it otherwise we will loose an handle
        ch.close();
        throw e;
    }
}
 

import java.nio.channels.DatagramChannel; //導入方法依賴的package包/類
public void run () {
    if (mIsConnected) return;
    try {
        mChannel = DatagramChannel.open();
        mChannel.configureBlocking(false);
        mChannel.connect(new InetSocketAddress(mAddress, mPort));

        if (mListenerThread == null) {
            mListenerThread = new ListenerThread();
            mListenerThread.start();
            mActivityHandler.sendMessage(composeMessage(MSG_ON_CONNECT, ""));
            mIsConnected = true;
        }

        Looper.prepare();
        mSendHandler = new Handler();
        Looper.loop();

    } catch (Exception e) {
        mActivityHandler.sendMessage(composeMessage(MSG_ON_CONNECTION_FAIL, e.toString()));
    }
}
 

import java.nio.channels.DatagramChannel; //導入方法依賴的package包/類
public static DatagramChannel launchWithDatagramChannel(String className, String options[], String args[])
    throws IOException
{
    DatagramChannel dc = DatagramChannel.open();
    dc.socket().bind(new InetSocketAddress(0));

    int port = dc.socket().getLocalPort();
    launch(className, options, args, Util.getFD(dc));
    dc.close();

    dc = DatagramChannel.open();
    InetAddress address = InetAddress.getLocalHost();
    if (address.isLoopbackAddress()) {
        address = InetAddress.getLoopbackAddress();
    }
    InetSocketAddress isa = new InetSocketAddress(address, port);

    dc.connect(isa);
    return dc;
}
 

import java.nio.channels.DatagramChannel; //導入方法依賴的package包/類
/**
     * resolves host, builds socket, returns true if it succeeds
     */
    private boolean checkSocket() {
        if ((channel != null) && channel.isOpen()) { //if(datagramSocket!=null && datagramSocket.isBound()) {
            return true;
        }
        try {
            channel = DatagramChannel.open();
            datagramSocket = channel.socket();
            datagramSocket.setReuseAddress(true);
            // disable timeout so that receive just waits for data forever (until interrupted)
//            datagramSocket.setSoTimeout(TIMEOUT_MS);
//            if (datagramSocket.getSoTimeout() != TIMEOUT_MS) {
//                log.warning("datagram socket read timeout value read=" + datagramSocket.getSoTimeout() + " which is different than timeout value of " + TIMEOUT_MS + " that we tried to set - perhaps timeout is not supported?");
//            }
            SocketAddress address = new InetSocketAddress(getPort());
            datagramSocket.bind(address);
            log.info("bound " + this);
            datagramSocket.setSoTimeout(0); // infinite timeout
            return true;
        } catch (IOException e) {
            log.warning("caught " + e + ", datagramSocket will be constructed later");
            return false;
        }
    }
 

import java.nio.channels.DatagramChannel; //導入方法依賴的package包/類
public synchronized void start() throws IOException {
    if (running) {
        return;
    }
    // Start channel
    DatagramChannel channel = DatagramChannel.open();
    channel.configureBlocking(true);
    channel.socket().bind(new InetSocketAddress(port));
    running = true;
    // Start server thread
    new ServerThread(channel).start();
    log.info("DNS server started");
}
 

import java.nio.channels.DatagramChannel; //導入方法依賴的package包/類
public static void main(String[] args) throws Exception {

        // Load necessary classes ahead of time
        DatagramChannel dc = DatagramChannel.open();
        Exception se = new SocketException();
        SelectorProvider sp = SelectorProvider.provider();
        Pipe p = sp.openPipe();
        ServerSocketChannel ssc = ServerSocketChannel.open();

        test1();
        test2();
        test3();
        test4();
    }
 

import java.nio.channels.DatagramChannel; //導入方法依賴的package包/類
protected void bind() throws IOException {
    // allocate an unbound server socket channel
    serverChannel = ServerSocketChannel.open();
    // Get the associated ServerSocket to bind it with
    ServerSocket serverSocket = serverChannel.socket();
    // create a new Selector for use below
    synchronized (Selector.class) {
        // Selector.open() isn't thread safe
        // http://bugs.sun.com/view_bug.do?bug_id=6427854
        // Affects 1.6.0_29, fixed in 1.7.0_01
        this.selector.set(Selector.open());
    }
    // set the port the server channel will listen to
    //serverSocket.bind(new InetSocketAddress(getBind(), getTcpListenPort()));
    bind(serverSocket,getPort(),getAutoBind());
    // set non-blocking mode for the listening socket
    serverChannel.configureBlocking(false);
    // register the ServerSocketChannel with the Selector
    serverChannel.register(this.selector.get(), SelectionKey.OP_ACCEPT);

    //set up the datagram channel
    if (this.getUdpPort()>0) {
        datagramChannel = DatagramChannel.open();
        configureDatagraChannel();
        //bind to the address to avoid security checks
        bindUdp(datagramChannel.socket(),getUdpPort(),getAutoBind());
    }
}
 

import java.nio.channels.DatagramChannel; //導入方法依賴的package包/類
static void wakeupWhenBound(final DatagramChannel dc) {
    Runnable wakeupTask = new Runnable() {
        public void run() {
            try {
                // poll for local address
                InetSocketAddress local;
                do {
                    Thread.sleep(50);
                    local = (InetSocketAddress)dc.getLocalAddress();
                } while (local == null);

                // send message to channel to wakeup receiver
                DatagramChannel sender = DatagramChannel.open();
                try {
                    ByteBuffer bb = ByteBuffer.wrap("hello".getBytes());
                    InetAddress lh = InetAddress.getLocalHost();
                    SocketAddress target =
                        new InetSocketAddress(lh, local.getPort());
                    sender.send(bb, target);
                } finally {
                    sender.close();
                }

            } catch (Exception x) {
                x.printStackTrace();
            }
        }};
    new Thread(wakeupTask).start();
}
 

import java.nio.channels.DatagramChannel; //導入方法依賴的package包/類
static void test2() {
    for (int i=0; i<11000; i++) {
        try {
            DatagramChannel sc = DatagramChannel.open();
        } catch (Exception e) {
            // Presumably "Too many open files"
        }
    }
}
 

import java.nio.channels.DatagramChannel; //導入方法依賴的package包/類
private static void test() throws Exception {
    DatagramChannel dc = DatagramChannel.open();
    InetAddress localHost = InetAddress.getLocalHost();
    dc.bind(new InetSocketAddress(localHost, 0));

    Server server = new Server(dc.getLocalAddress());
    Thread serverThread = new Thread(server);
    serverThread.start();

    try {
        InetSocketAddress isa = new InetSocketAddress(localHost, server.port());
        dc.connect(isa);

        ByteBuffer bb = ByteBuffer.allocateDirect(12);
        bb.order(ByteOrder.BIG_ENDIAN);
        bb.putInt(1).putLong(1);
        bb.flip();

        dc.write(bb);
        bb.rewind();
        dc.write(bb);
        bb.rewind();
        dc.write(bb);

        Thread.sleep(2000);

        serverThread.interrupt();
        server.throwException();
    } finally {
        dc.close();
    }
}
 

import java.nio.channels.DatagramChannel; //導入方法依賴的package包/類
/**
 * connect - blocking in this operation
 *
 * @throws IOException
 * TODO Implement this org.apache.catalina.tribes.transport.IDataSender method
 */
@Override
public synchronized void connect() throws IOException {
    if ( connecting || isConnected()) return;
    connecting = true;
    if ( isConnected() ) throw new IOException("NioSender is already in connected state.");
    if ( readbuf == null ) {
        readbuf = getReadBuffer();
    } else {
        readbuf.clear();
    }
    if ( writebuf == null ) {
        writebuf = getWriteBuffer();
    } else {
        writebuf.clear();
    }

    if (isUdpBased()) {
        InetSocketAddress daddr = new InetSocketAddress(getAddress(),getUdpPort());
        if ( dataChannel != null ) throw new IOException("Datagram channel has already been established. Connection might be in progress.");
        dataChannel = DatagramChannel.open();
        configureSocket();
        dataChannel.connect(daddr);
        completeConnect();
        dataChannel.register(getSelector(),SelectionKey.OP_WRITE, this);
        
    } else {
        InetSocketAddress addr = new InetSocketAddress(getAddress(),getPort());
        if ( socketChannel != null ) throw new IOException("Socket channel has already been established. Connection might be in progress.");
        socketChannel = SocketChannel.open();
        configureSocket();
        if ( socketChannel.connect(addr) ) {
            completeConnect();
            socketChannel.register(getSelector(), SelectionKey.OP_WRITE, this);
        } else {
            socketChannel.register(getSelector(), SelectionKey.OP_CONNECT, this);
        }
    }
}
 

import java.nio.channels.DatagramChannel; //導入方法依賴的package包/類
private void openChannel() {
    try {
        channel = DatagramChannel.open();
        channel.socket().bind(new InetSocketAddress(DEFAULT_PORT));
    } catch (IOException e) {
        e.printStackTrace();
    }
}
 

import java.nio.channels.DatagramChannel; //導入方法依賴的package包/類
private void openChannel() throws IOException {
    closeChannel();
    keepRunning = true;
    channel = DatagramChannel.open();
    localSocketAddress = new InetSocketAddress("192.168.1.161", localPort);
    channel.bind(localSocketAddress);
    log.info("opened channel on local port " + localSocketAddress + " to receive UDP messages from ROS.");
}