Example usage for java.nio ByteBuffer get

List of usage examples for java.nio ByteBuffer get

Introduction

In this page you can find the example usage for java.nio ByteBuffer get.

Prototype

public ByteBuffer get(byte[] dest, int off, int len) 

Source Link

Document

Reads bytes from the current position into the specified byte array, starting at the specified offset, and increases the position by the number of bytes read.

Usage

From source file:Main.java

public static void main(String[] argv) throws Exception {
    byte[] bytes = new byte[10];
    ByteBuffer buf = ByteBuffer.wrap(bytes);

    bytes = new byte[buf.remaining()];
    buf.get(bytes, 0, bytes.length);
}

From source file:Main.java

public static void main(String[] argv) throws Exception {
    byte[] bytes = new byte[10];
    ByteBuffer buf = ByteBuffer.wrap(bytes);

    buf.clear();/*w w w . j a  va 2  s. c  om*/
    bytes = new byte[buf.capacity()];
    buf.get(bytes, 0, bytes.length);

}

From source file:Main.java

public static void main(String[] args) {
    ByteBuffer bb = ByteBuffer.allocate(BSIZE);
    bb.asCharBuffer().put("java2s!");
    byte[] dst = new byte[BSIZE];
    bb.rewind();/*  www.ja v  a  2 s  .  c  om*/
    bb.get(dst, 0, 3);
    System.out.println(Arrays.toString(dst));

}

From source file:Main.java

public static void main(String[] argv) throws Exception {
    // Create a ByteBuffer from a byte array
    byte[] bytes = new byte[10];
    ByteBuffer buffer = ByteBuffer.wrap(bytes);

    // Retrieve bytes between the position and limit
    bytes = new byte[buffer.remaining()];
    buffer.get(bytes, 0, bytes.length);

    // Retrieve all bytes in the buffer
    buffer.clear();/*from   w ww  . j a va 2  s  .c  om*/
    bytes = new byte[buffer.capacity()];
    buffer.get(bytes, 0, bytes.length);
}

From source file:Main.java

public static void main(String[] args) throws Exception {
    MembershipKey key = null;//from w  w w.jav a  2s  . c o m
    DatagramChannel client = DatagramChannel.open(StandardProtocolFamily.INET);

    NetworkInterface interf = NetworkInterface.getByName(MULTICAST_INTERFACE_NAME);
    client.setOption(StandardSocketOptions.SO_REUSEADDR, true);
    client.bind(new InetSocketAddress(MULTICAST_PORT));
    client.setOption(StandardSocketOptions.IP_MULTICAST_IF, interf);

    InetAddress group = InetAddress.getByName(MULTICAST_IP);
    key = client.join(group, interf);

    System.out.println("Joined the   multicast  group:" + key);
    System.out.println("Waiting for a  message  from  the" + "  multicast group....");

    ByteBuffer buffer = ByteBuffer.allocate(1048);
    client.receive(buffer);
    buffer.flip();
    int limits = buffer.limit();
    byte bytes[] = new byte[limits];
    buffer.get(bytes, 0, limits);
    String msg = new String(bytes);

    System.out.format("Multicast Message:%s%n", msg);
    key.drop();
}

From source file:Main.java

public static void main(String[] args) throws Exception {
    DatagramChannel client = null;
    client = DatagramChannel.open();

    client.bind(null);//from   w  ww .  j a  va  2 s  .  com

    String msg = "Hello";
    ByteBuffer buffer = ByteBuffer.wrap(msg.getBytes());
    InetSocketAddress serverAddress = new InetSocketAddress("localhost", 8989);

    client.send(buffer, serverAddress);
    buffer.clear();
    client.receive(buffer);
    buffer.flip();
    int limits = buffer.limit();
    byte bytes[] = new byte[limits];
    buffer.get(bytes, 0, limits);
    String response = new String(bytes);
    System.out.println("Server  responded: " + response);
    client.close();
}

From source file:Main.java

public static void main(String[] args) throws Exception {
    DatagramChannel server = null;
    server = DatagramChannel.open();
    InetSocketAddress sAddr = new InetSocketAddress("localhost", 8989);
    server.bind(sAddr);/*from   www.ja  va 2  s  .c o m*/
    ByteBuffer buffer = ByteBuffer.allocate(1024);

    while (true) {
        System.out.println("Waiting for a  message  from" + "  a  remote  host at " + sAddr);
        SocketAddress remoteAddr = server.receive(buffer);
        buffer.flip();
        int limits = buffer.limit();
        byte bytes[] = new byte[limits];
        buffer.get(bytes, 0, limits);
        String msg = new String(bytes);

        System.out.println("Client at " + remoteAddr + "  says: " + msg);
        buffer.rewind();
        server.send(buffer, remoteAddr);
        buffer.clear();
    }
    //server.close();
}

From source file:CTmousetrack.java

public static void main(String[] args) {

    String outLoc = new String("." + File.separator + "CTdata"); // Location of the base output data folder; only used when writing out CT data to a local folder
    String srcName = "CTmousetrack"; // name of the output CT source
    long blockPts = 10; // points per block flush
    long sampInterval = 10; // time between sampling updates, msec
    double trimTime = 0.0; // amount of data to keep (trim time), sec
    boolean debug = false; // turn on debug?

    // Specify the CT output connection
    CTWriteMode writeMode = CTWriteMode.LOCAL; // The selected mode for writing out CT data
    String serverHost = ""; // Server (FTP or HTTP/S) host:port
    String serverUser = ""; // Server (FTP or HTTPS) username
    String serverPassword = ""; // Server (FTP or HTTPS) password

    // For UDP output mode
    DatagramSocket udpServerSocket = null;
    InetAddress udpServerAddress = null;
    String udpHost = "";
    int udpPort = -1;

    // Concatenate all of the CTWriteMode types
    String possibleWriteModes = "";
    for (CTWriteMode wm : CTWriteMode.values()) {
        possibleWriteModes = possibleWriteModes + ", " + wm.name();
    }/*from   w  w w.  j a v  a 2  s  . co m*/
    // Remove ", " from start of string
    possibleWriteModes = possibleWriteModes.substring(2);

    //
    // Argument processing using Apache Commons CLI
    //
    // 1. Setup command line options
    Options options = new Options();
    options.addOption("h", "help", false, "Print this message.");
    options.addOption(Option.builder("o").argName("base output dir").hasArg().desc(
            "Base output directory when writing data to local folder (i.e., this is the location of CTdata folder); default = \""
                    + outLoc + "\".")
            .build());
    options.addOption(Option.builder("s").argName("source name").hasArg()
            .desc("Name of source to write data to; default = \"" + srcName + "\".").build());
    options.addOption(Option.builder("b").argName("points per block").hasArg()
            .desc("Number of points per block; UDP output mode will use 1 point/block; default = "
                    + Long.toString(blockPts) + ".")
            .build());
    options.addOption(Option.builder("dt").argName("samp interval msec").hasArg()
            .desc("Sampling period in msec; default = " + Long.toString(sampInterval) + ".").build());
    options.addOption(Option.builder("t").argName("trim time sec").hasArg().desc(
            "Trim (ring-buffer loop) time (sec); this is only used when writing data to local folder; specify 0 for indefinite; default = "
                    + Double.toString(trimTime) + ".")
            .build());
    options.addOption(
            Option.builder("w").argName("write mode").hasArg()
                    .desc("Type of write connection; one of " + possibleWriteModes
                            + "; all but UDP mode write out to CT; default = " + writeMode.name() + ".")
                    .build());
    options.addOption(Option.builder("host").argName("host[:port]").hasArg()
            .desc("Host:port when writing via FTP, HTTP, HTTPS, UDP.").build());
    options.addOption(Option.builder("u").argName("username,password").hasArg()
            .desc("Comma-delimited username and password when writing to CT via FTP or HTTPS.").build());
    options.addOption("x", "debug", false, "Enable CloudTurbine debug output.");

    // 2. Parse command line options
    CommandLineParser parser = new DefaultParser();
    CommandLine line = null;
    try {
        line = parser.parse(options, args);
    } catch (ParseException exp) { // oops, something went wrong
        System.err.println("Command line argument parsing failed: " + exp.getMessage());
        return;
    }

    // 3. Retrieve the command line values
    if (line.hasOption("help")) { // Display help message and quit
        HelpFormatter formatter = new HelpFormatter();
        formatter.setWidth(120);
        formatter.printHelp("CTmousetrack", "", options,
                "NOTE: UDP output is a special non-CT output mode where single x,y points are sent via UDP to the specified host:port.");
        return;
    }

    outLoc = line.getOptionValue("o", outLoc);
    if (!outLoc.endsWith("\\") && !outLoc.endsWith("/")) {
        outLoc = outLoc + File.separator;
    }
    // Make sure the base output folder location ends in "CTdata"
    if (!outLoc.endsWith("CTdata\\") && !outLoc.endsWith("CTdata/")) {
        outLoc = outLoc + "CTdata" + File.separator;
    }

    srcName = line.getOptionValue("s", srcName);

    blockPts = Long.parseLong(line.getOptionValue("b", Long.toString(blockPts)));

    sampInterval = Long.parseLong(line.getOptionValue("dt", Long.toString(sampInterval)));

    trimTime = Double.parseDouble(line.getOptionValue("t", Double.toString(trimTime)));

    // Type of output connection
    String writeModeStr = line.getOptionValue("w", writeMode.name());
    boolean bMatch = false;
    for (CTWriteMode wm : CTWriteMode.values()) {
        if (wm.name().toLowerCase().equals(writeModeStr.toLowerCase())) {
            writeMode = wm;
            bMatch = true;
        }
    }
    if (!bMatch) {
        System.err.println("Unrecognized write mode, \"" + writeModeStr + "\"; write mode must be one of "
                + possibleWriteModes);
        System.exit(0);
    }
    if (writeMode != CTWriteMode.LOCAL) {
        // User must have specified the host
        // If FTP or HTTPS, they may also specify username/password
        serverHost = line.getOptionValue("host", serverHost);
        if (serverHost.isEmpty()) {
            System.err.println(
                    "When using write mode \"" + writeModeStr + "\", you must specify the server host.");
            System.exit(0);
        }
        if (writeMode == CTWriteMode.UDP) {
            // Force blockPts to be 1
            blockPts = 1;
            // User must have specified both host and port
            int colonIdx = serverHost.indexOf(':');
            if ((colonIdx == -1) || (colonIdx >= serverHost.length() - 1)) {
                System.err.println(
                        "For UDP output mode, both the host and port (<host>:<port>)) must be specified.");
                System.exit(0);
            }
            udpHost = serverHost.substring(0, colonIdx);
            String udpPortStr = serverHost.substring(colonIdx + 1);
            try {
                udpPort = Integer.parseInt(udpPortStr);
            } catch (NumberFormatException nfe) {
                System.err.println("The UDP port must be a positive integer.");
                System.exit(0);
            }
        }
        if ((writeMode == CTWriteMode.FTP) || (writeMode == CTWriteMode.HTTPS)) {
            String userpassStr = line.getOptionValue("u", "");
            if (!userpassStr.isEmpty()) {
                // This string should be comma-delimited username and password
                String[] userpassCSV = userpassStr.split(",");
                if (userpassCSV.length != 2) {
                    System.err.println("When specifying a username and password for write mode \""
                            + writeModeStr + "\", separate the username and password by a comma.");
                    System.exit(0);
                }
                serverUser = userpassCSV[0];
                serverPassword = userpassCSV[1];
            }
        }
    }

    debug = line.hasOption("debug");

    System.err.println("CTmousetrack parameters:");
    System.err.println("\toutput mode = " + writeMode.name());
    if (writeMode == CTWriteMode.UDP) {
        System.err.println("\twrite to " + udpHost + ":" + udpPort);
    } else {
        System.err.println("\tsource = " + srcName);
        System.err.println("\ttrim time = " + trimTime + " sec");
    }
    System.err.println("\tpoints per block = " + blockPts);
    System.err.println("\tsample interval = " + sampInterval + " msec");

    try {
        //
        // Setup CTwriter or UDP output
        //
        CTwriter ctw = null;
        CTinfo.setDebug(debug);
        if (writeMode == CTWriteMode.LOCAL) {
            ctw = new CTwriter(outLoc + srcName, trimTime);
            System.err.println("\tdata will be written to local folder \"" + outLoc + "\"");
        } else if (writeMode == CTWriteMode.FTP) {
            CTftp ctftp = new CTftp(srcName);
            try {
                ctftp.login(serverHost, serverUser, serverPassword);
            } catch (Exception e) {
                throw new IOException(
                        new String("Error logging into FTP server \"" + serverHost + "\":\n" + e.getMessage()));
            }
            ctw = ctftp; // upcast to CTWriter
            System.err.println("\tdata will be written to FTP server at " + serverHost);
        } else if (writeMode == CTWriteMode.HTTP) {
            // Don't send username/pw in HTTP mode since they will be unencrypted
            CThttp cthttp = new CThttp(srcName, "http://" + serverHost);
            ctw = cthttp; // upcast to CTWriter
            System.err.println("\tdata will be written to HTTP server at " + serverHost);
        } else if (writeMode == CTWriteMode.HTTPS) {
            CThttp cthttp = new CThttp(srcName, "https://" + serverHost);
            // Username/pw are optional for HTTPS mode; only use them if username is not empty
            if (!serverUser.isEmpty()) {
                try {
                    cthttp.login(serverUser, serverPassword);
                } catch (Exception e) {
                    throw new IOException(new String(
                            "Error logging into HTTP server \"" + serverHost + "\":\n" + e.getMessage()));
                }
            }
            ctw = cthttp; // upcast to CTWriter
            System.err.println("\tdata will be written to HTTPS server at " + serverHost);
        } else if (writeMode == CTWriteMode.UDP) {
            try {
                udpServerSocket = new DatagramSocket();
            } catch (SocketException se) {
                System.err.println("Error creating socket for UDP:\n" + se);
                System.exit(0);
            }
            try {
                udpServerAddress = InetAddress.getByName(udpHost);
            } catch (UnknownHostException uhe) {
                System.err.println("Error getting UDP server host address:\n" + uhe);
                System.exit(0);
            }
        }
        if (writeMode != CTWriteMode.UDP) {
            ctw.setBlockMode(blockPts > 1, blockPts > 1);
            ctw.autoFlush(0); // no autoflush
            ctw.autoSegment(1000);
        }

        // screen dims
        Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
        double width = screenSize.getWidth();
        double height = screenSize.getHeight();

        // use Map for consolidated putData
        Map<String, Object> cmap = new LinkedHashMap<String, Object>();

        // loop and write some output
        for (int i = 0; i < 1000000; i++) { // go until killed
            long currentTime = System.currentTimeMillis();
            Point mousePos = MouseInfo.getPointerInfo().getLocation();
            float x_pt = (float) (mousePos.getX() / width); // normalize
            float y_pt = (float) ((height - mousePos.getY()) / height); // flip Y (so bottom=0)
            if (writeMode != CTWriteMode.UDP) {
                // CT output mode
                ctw.setTime(currentTime);
                cmap.clear();
                cmap.put("x", x_pt);
                cmap.put("y", y_pt);
                ctw.putData(cmap);
                if (((i + 1) % blockPts) == 0) {
                    ctw.flush();
                    System.err.print(".");
                }
            } else {
                // UDP output mode
                // We force blockPts to be 1 for UDP output mode, i.e. we "flush" the data every time
                // Write the following data (21 bytes total):
                //     header = "MOUSE", 5 bytes
                //     current time, long, 8 bytes
                //     2 floats (x,y) 4 bytes each, 8 bytes
                int len = 21;
                ByteBuffer bb = ByteBuffer.allocate(len);
                String headerStr = "MOUSE";
                bb.put(headerStr.getBytes("UTF-8"));
                bb.putLong(currentTime);
                bb.putFloat(x_pt);
                bb.putFloat(y_pt);
                // Might be able to use the following, but not sure:
                //     byte[] sendData = bb.array();
                byte[] sendData = new byte[len];
                bb.position(0);
                bb.get(sendData, 0, len);
                DatagramPacket sendPacket = new DatagramPacket(sendData, sendData.length, udpServerAddress,
                        udpPort);
                try {
                    udpServerSocket.send(sendPacket);
                } catch (IOException e) {
                    System.err.println("Test server caught exception trying to send data to UDP client:\n" + e);
                }
                System.err.print(".");
            }
            try {
                Thread.sleep(sampInterval);
            } catch (Exception e) {
            }
            ;
        }
        if (writeMode != CTWriteMode.UDP) {
            ctw.flush(); // wrap up
        }
    } catch (Exception e) {
        System.err.println("CTmousetrack exception: " + e);
        e.printStackTrace();
    }
}

From source file:Main.java

public static byte[] bufferToBytes(ByteBuffer byteBuffer) {
    byte[] bytes = new byte[byteBuffer.remaining()];
    byteBuffer.get(bytes, 0, bytes.length);
    return bytes;
}

From source file:de.zalando.spring.cloud.config.aws.kms.KmsTextEncryptor.java

private static String extractString(final ByteBuffer bb) {
    if (bb.hasRemaining()) {
        final byte[] bytes = new byte[bb.remaining()];
        bb.get(bytes, bb.arrayOffset(), bb.remaining());
        return new String(bytes);
    } else {//from w w w .ja  va2 s .  c  o  m
        return EMPTY_STRING;
    }
}