Example usage for java.nio ByteBuffer clear

List of usage examples for java.nio ByteBuffer clear

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Introduction

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

Prototype

public final Buffer clear()

Source Link

Document

Clears this buffer.

Usage

From source file:org.apache.jxtadoop.hdfs.server.datanode.BlockSender.java

/**
 * Sends upto maxChunks chunks of data./*from   w  w w  .j av  a2 s.c  om*/
 * 
 * When blockInPosition is >= 0, assumes 'out' is a 
 * {@link SocketOutputStream} and tries 
 * {@link SocketOutputStream#transferToFully(FileChannel, long, int)} to
 * send data (and updates blockInPosition).
 */
private int sendChunks(ByteBuffer pkt, int maxChunks, OutputStream out) throws IOException {
    // Sends multiple chunks in one packet with a single write().

    int len = Math.min((int) (endOffset - offset), bytesPerChecksum * maxChunks);
    if (len == 0) {
        return 0;
    }

    int numChunks = (len + bytesPerChecksum - 1) / bytesPerChecksum;
    int packetLen = len + numChunks * checksumSize + 4;
    pkt.clear();

    // write packet header
    pkt.putInt(packetLen);
    pkt.putLong(offset);
    pkt.putLong(seqno);
    pkt.put((byte) ((offset + len >= endOffset) ? 1 : 0));
    //why no ByteBuf.putBoolean()?
    pkt.putInt(len);

    int checksumOff = pkt.position();
    int checksumLen = numChunks * checksumSize;
    byte[] buf = pkt.array();

    if (checksumSize > 0 && checksumIn != null) {
        try {
            checksumIn.readFully(buf, checksumOff, checksumLen);
        } catch (IOException e) {
            LOG.warn(" Could not read or failed to veirfy checksum for data" + " at offset " + offset
                    + " for block " + block + " got : " + StringUtils.stringifyException(e));
            IOUtils.closeStream(checksumIn);
            checksumIn = null;
            if (corruptChecksumOk) {
                if (checksumOff < checksumLen) {
                    // Just fill the array with zeros.
                    Arrays.fill(buf, checksumOff, checksumLen, (byte) 0);
                }
            } else {
                throw e;
            }
        }
    }

    int dataOff = checksumOff + checksumLen;

    if (blockInPosition < 0) {
        //normal transfer
        IOUtils.readFully(blockIn, buf, dataOff, len);

        if (verifyChecksum) {
            int dOff = dataOff;
            int cOff = checksumOff;
            int dLeft = len;

            for (int i = 0; i < numChunks; i++) {
                checksum.reset();
                int dLen = Math.min(dLeft, bytesPerChecksum);
                checksum.update(buf, dOff, dLen);
                if (!checksum.compare(buf, cOff)) {
                    throw new ChecksumException("Checksum failed at " + (offset + len - dLeft), len);
                }
                dLeft -= dLen;
                dOff += dLen;
                cOff += checksumSize;
            }
        }
        //writing is done below (mainly to handle IOException)
    }

    try {
        if (blockInPosition >= 0) {
            //use transferTo(). Checks on out and blockIn are already done. 

            SocketOutputStream sockOut = (SocketOutputStream) out;
            //first write the packet
            sockOut.write(buf, 0, dataOff);
            // no need to flush. since we know out is not a buffered stream. 

            sockOut.transferToFully(((FileInputStream) blockIn).getChannel(), blockInPosition, len);

            blockInPosition += len;
        } else {
            // normal transfer
            out.write(buf, 0, dataOff + len);
        }

    } catch (IOException e) {
        /* exception while writing to the client (well, with transferTo(),
         * it could also be while reading from the local file).
         */
        throw ioeToSocketException(e);
    }

    if (throttler != null) { // rebalancing so throttle
        throttler.throttle(packetLen);
    }

    return len;
}

From source file:cn.ac.ncic.mastiff.io.coding.RLEDecoder.java

@Override
public byte[] ensureDecompressed() throws IOException {
    FlexibleEncoding.ORC.DynamicByteArray dynamicBuffer = new FlexibleEncoding.ORC.DynamicByteArray();
    dynamicBuffer.add(inBuf.getData(), 12, inBuf.getLength() - 12);
    ByteBuffer byteBuf = ByteBuffer.allocate(dynamicBuffer.size());
    dynamicBuffer.setByteBuffer(byteBuf, 0, dynamicBuffer.size());
    byteBuf.flip();//from ww  w.j a  v  a  2s. c  om
    FlexibleEncoding.ORC.InStream instream = FlexibleEncoding.ORC.InStream.create("test", byteBuf, null,
            dynamicBuffer.size());
    RunLengthIntegerReader rlein = new RunLengthIntegerReader(instream, true);
    DataOutputBuffer decoding = new DataOutputBuffer();
    decoding.writeInt(decompressedSize);
    decoding.writeInt(numPairs);
    decoding.writeInt(startPos);
    for (int i = 1; i < numPairs; i++) {
        int tmp = (int) rlein.next();
        decoding.writeInt(tmp);
    }
    byteBuf.clear();
    inBuf.close();
    return decoding.getData();
}

From source file:org.openhealthtools.openatna.syslog.protocol.ProtocolMessageFactory.java

/**
 * This reads up to 256 characters to read headers (excluding SDs). This limit is arbitrary.
 * It is imposed to reduce the risk/*from w  ww.ja va  2  s.c om*/
 * of badly formed or malicious messages from using too many resources.
 *
 * @param in
 * @return
 * @throws SyslogException
 */
public SyslogMessage read(InputStream in) throws SyslogException {
    try {
        PushbackInputStream pin = new PushbackInputStream(in, 5);
        int priority = readPriority(pin);
        int facility;
        int severity;
        byte c;
        int spaces = 5;
        int count = 0;
        ByteBuffer buff = ByteBuffer.wrap(new byte[256]);

        String timestamp = null;
        String host = "-";
        String app = "-";
        String proc = "-";
        String mid = "-";
        int max = 256;
        int curr = 0;

        while (count < spaces && curr < max) {
            c = (byte) pin.read();
            curr++;
            if (c == ' ') {
                count++;
                String currHeader = new String(buff.array(), 0, buff.position(), Constants.ENC_UTF8);
                buff.clear();
                switch (count) {
                case 1:
                    timestamp = currHeader;
                    break;
                case 2:
                    host = currHeader;
                    break;
                case 3:
                    app = currHeader;
                    break;
                case 4:
                    proc = currHeader;
                    break;
                case 5:
                    mid = currHeader;
                    break;
                }
            } else {
                buff.put(c);
            }
        }
        if (timestamp == null) {
            throw new SyslogException("no timestamp defined");
        }

        c = (byte) pin.read();
        List<StructuredElement> els = new ArrayList<StructuredElement>();
        if (c == '-') {
            c = (byte) pin.read();
            if (c != ' ') {
                throw new SyslogException("not a space");
            }
        } else if (c == '[') {
            pin.unread(c);
            els = StructuredElement.parse(pin);
        } else {
            throw new SyslogException("Illegal Structured data");
        }
        LogMessage logMessage = getLogMessage(mid);
        String encoding = readBom(pin, logMessage.getExpectedEncoding());
        logMessage.read(pin, encoding);
        facility = priority / 8;
        severity = priority % 8;
        ProtocolMessage sm = new ProtocolMessage(facility, severity, timestamp, host, logMessage, app, mid,
                proc);
        for (StructuredElement el : els) {
            sm.addStructuredElement(el);
        }
        return sm;
    } catch (IOException e) {
        e.printStackTrace();
        throw new SyslogException(e);
    }
}

From source file:com.google.cloud.hadoop.gcsio.GoogleCloudStorageIntegrationHelper.java

/**
 * Helper which reads the entire file as a String.
 *///from   w ww  .  j a v a  2 s .  c o m
protected String readTextFile(String bucketName, String objectName) throws IOException {
    SeekableReadableByteChannel readChannel = null;
    ByteBuffer readBuffer = ByteBuffer.allocate(1024);
    StringBuffer returnBuffer = new StringBuffer();

    try {
        readChannel = open(bucketName, objectName);
        int numBytesRead = readChannel.read(readBuffer);
        while (numBytesRead > 0) {
            readBuffer.flip();
            returnBuffer.append(StandardCharsets.UTF_8.decode(readBuffer));
            readBuffer.clear();
            numBytesRead = readChannel.read(readBuffer);
        }
    } finally {
        if (readChannel != null) {
            readChannel.close();
        }
    }
    return returnBuffer.toString();
}

From source file:de.digitalcollections.streaming.euphoria.controller.StreamingController.java

/**
 * Stream the given input to the given output via NIO {@link Channels} and a directly allocated NIO
 * {@link ByteBuffer}. Both the input and output streams will implicitly be closed after streaming, regardless of
 * whether an exception is been thrown or not.
 *
 * @param input The input stream.//w  w w  .  j  a v  a 2 s.com
 * @param output The output stream.
 * @return The length of the written bytes.
 * @throws IOException When an I/O error occurs.
 */
private long stream(InputStream input, OutputStream output) throws IOException {
    try (ReadableByteChannel inputChannel = Channels.newChannel(input);
            WritableByteChannel outputChannel = Channels.newChannel(output)) {
        ByteBuffer buffer = ByteBuffer.allocateDirect(DEFAULT_STREAM_BUFFER_SIZE);
        long size = 0;

        while (inputChannel.read(buffer) != -1) {
            buffer.flip();
            size += outputChannel.write(buffer);
            buffer.clear();
        }

        return size;
    }
}

From source file:cn.ac.ncic.mastiff.io.coding.RunLengthEncodingIntReader.java

@Override
public byte[] ensureDecompressed() throws IOException {
    FlexibleEncoding.ORC.DynamicByteArray dynamicBuffer = new FlexibleEncoding.ORC.DynamicByteArray();
    dynamicBuffer.add(inBuf.getData(), 12, inBuf.getLength() - 12);
    ByteBuffer byteBuf = ByteBuffer.allocate(dynamicBuffer.size());
    dynamicBuffer.setByteBuffer(byteBuf, 0, dynamicBuffer.size());
    byteBuf.flip();/*w  ww  .ja va2s.  c  om*/
    FlexibleEncoding.ORC.InStream instream = FlexibleEncoding.ORC.InStream.create("test", byteBuf, null,
            dynamicBuffer.size());
    RunLengthIntegerReader rlein = new RunLengthIntegerReader(instream, true);
    DataOutputBuffer decoding = new DataOutputBuffer();
    decoding.writeInt(decompressedSize);
    decoding.writeInt(numPairs);
    decoding.writeInt(startPos);
    for (int i = 0; i < numPairs; i++) {
        int tmp = (int) rlein.next();
        decoding.writeInt(tmp);
    }
    byteBuf.clear();
    inBuf.close();
    return decoding.getData();

}

From source file:net.jenet.Host.java

/**
 * @param buffer/*from   ww  w.ja va2s.  c  o m*/
 * @return
 */
int receive(ByteBuffer buffer) {
    try {
        buffer.clear();
        receivedAddress = (InetSocketAddress) communicationChannel.receive(buffer);
        buffer.flip();
        if (receivedAddress != null)
            LOG.debug("Host.receive:" + address + ". Received " + buffer.limit() + " bytes  from "
                    + receivedAddress);
        return buffer.limit();
    } catch (Exception e) {
        LOG.error("Host.receive: Error reading buffers.", e);
        return -1;
    }
}

From source file:cn.ac.ncic.mastiff.io.coding.RunLengthEncodingByteReader.java

public byte[] CompressensureDecompressed() throws IOException {
    FlexibleEncoding.ORC.DynamicByteArray dynamicBuffer = new FlexibleEncoding.ORC.DynamicByteArray();
    dynamicBuffer.add(inBuf.getData(), 0, inBuf.getLength());
    ByteBuffer byteBuf = ByteBuffer.allocate(dynamicBuffer.size());
    dynamicBuffer.setByteBuffer(byteBuf, 0, dynamicBuffer.size());
    byteBuf.flip();//from  www .ja  v a2s  . c  o m
    FlexibleEncoding.ORC.InStream instream = FlexibleEncoding.ORC.InStream.create("test", byteBuf, null,
            dynamicBuffer.size());
    RunLengthByteReader rlein = new RunLengthByteReader(instream);
    DataOutputBuffer decoding = new DataOutputBuffer();
    decoding.writeInt(decompressedSize);
    decoding.writeInt(numPairs);
    decoding.writeInt(startPos);
    for (int i = 0; i < numPairs; i++) {
        byte tmp = rlein.next();
        decoding.writeByte(tmp);
    }
    byteBuf.clear();
    inBuf.close();
    return decoding.getData();
}

From source file:cn.ac.ncic.mastiff.io.coding.RunLengthEncodingByteReader.java

@Override
public byte[] ensureDecompressed() throws IOException {
    //  byte[]  bytes=inBuf.getData() ;
    FlexibleEncoding.ORC.DynamicByteArray dynamicBuffer = new FlexibleEncoding.ORC.DynamicByteArray();
    dynamicBuffer.add(inBuf.getData(), 12, inBuf.getLength() - 12);
    ByteBuffer byteBuf = ByteBuffer.allocate(dynamicBuffer.size());
    dynamicBuffer.setByteBuffer(byteBuf, 0, dynamicBuffer.size());
    byteBuf.flip();/*  www .j  a v a2 s  .  c o m*/
    FlexibleEncoding.ORC.InStream instream = FlexibleEncoding.ORC.InStream.create("test", byteBuf, null,
            dynamicBuffer.size());
    RunLengthByteReader rlein = new RunLengthByteReader(instream);
    DataOutputBuffer decoding = new DataOutputBuffer();
    decoding.writeInt(decompressedSize);
    decoding.writeInt(numPairs);
    decoding.writeInt(startPos);
    for (int i = 0; i < numPairs; i++) {
        byte tmp = rlein.next();
        decoding.writeByte(tmp);
    }
    byteBuf.clear();
    inBuf.close();
    return decoding.getData();
}

From source file:org.apache.hadoop.hdfs.server.datanode.RaidBlockSender.java

/**
 * Sends upto maxChunks chunks of data./*from w w  w.  ja va  2s .  c  o  m*/
 * 
 * When blockInPosition is >= 0, assumes 'out' is a 
 * {@link SocketOutputStream} and tries 
 * {@link SocketOutputStream#transferToFully(FileChannel, long, int)} to
 * send data (and updates blockInPosition).
 */
private int sendChunks(ByteBuffer pkt, int maxChunks, OutputStream out) throws IOException {
    // Sends multiple chunks in one packet with a single write().

    int len = (int) Math.min(endOffset - offset, (((long) bytesPerChecksum) * ((long) maxChunks)));
    int numChunks = (len + bytesPerChecksum - 1) / bytesPerChecksum;
    int packetLen = len + numChunks * checksumSize + 4;
    boolean lastDataPacket = offset + len == endOffset && len > 0;
    pkt.clear();

    PacketHeader header = new PacketHeader(packetLen, offset, seqno, (len == 0), len);
    header.putInBuffer(pkt);

    int checksumOff = pkt.position();
    int checksumLen = numChunks * checksumSize;
    byte[] buf = pkt.array();

    if (checksumSize > 0 && checksumIn != null) {
        try {
            checksumIn.readFully(buf, checksumOff, checksumLen);
        } catch (IOException e) {
            LOG.warn(" Could not read or failed to veirfy checksum for data" + " at offset " + offset
                    + " for block " + block + " got : " + StringUtils.stringifyException(e));
            IOUtils.closeStream(checksumIn);
            checksumIn = null;
            if (corruptChecksumOk) {
                if (checksumOff < checksumLen) {
                    // Just fill the array with zeros.
                    Arrays.fill(buf, checksumOff, checksumLen, (byte) 0);
                }
            } else {
                throw e;
            }
        }

        // write in progress that we need to use to get last checksum
        if (lastDataPacket && lastChunkChecksum != null) {
            int start = checksumOff + checksumLen - checksumSize;
            byte[] updatedChecksum = lastChunkChecksum.getChecksum();

            if (updatedChecksum != null) {
                System.arraycopy(updatedChecksum, 0, buf, start, checksumSize);
            }
        }
    }

    int dataOff = checksumOff + checksumLen;

    if (blockInPosition < 0) {
        //normal transfer
        IOUtils.readFully(blockIn, buf, dataOff, len);

        if (verifyChecksum) {
            int dOff = dataOff;
            int cOff = checksumOff;
            int dLeft = len;

            for (int i = 0; i < numChunks; i++) {
                checksum.reset();
                int dLen = Math.min(dLeft, bytesPerChecksum);
                checksum.update(buf, dOff, dLen);
                if (!checksum.compare(buf, cOff)) {
                    long failedPos = offset + len - dLeft;
                    throw new ChecksumException("Checksum failed at " + failedPos, failedPos);
                }
                dLeft -= dLen;
                dOff += dLen;
                cOff += checksumSize;
            }
        }
        //writing is done below (mainly to handle IOException)
    }

    try {
        if (blockInPosition >= 0) {
            //use transferTo(). Checks on out and blockIn are already done. 

            SocketOutputStream sockOut = (SocketOutputStream) out;
            //first write the packet
            sockOut.write(buf, 0, dataOff);
            // no need to flush. since we know out is not a buffered stream. 

            sockOut.transferToFully(((FileInputStream) blockIn).getChannel(), blockInPosition, len);

            blockInPosition += len;
        } else {
            // normal transfer
            out.write(buf, 0, dataOff + len);
        }

    } catch (IOException e) {
        /* exception while writing to the client (well, with transferTo(),
         * it could also be while reading from the local file).
         */
        throw ioeToSocketException(e);
    }

    return len;
}