Example usage for java.nio.channels FileChannel read

List of usage examples for java.nio.channels FileChannel read

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Introduction

In this page you can find the example usage for java.nio.channels FileChannel read.

Prototype

public final long read(ByteBuffer[] dsts) throws IOException

Source Link

Document

Reads a sequence of bytes from this channel into the given buffers.

Usage

From source file:org.hawk.service.api.utils.APIUtils.java

public static File convertJavaFileToThriftFile(java.io.File rawFile) throws FileNotFoundException, IOException {
    try (FileInputStream fIS = new FileInputStream(rawFile)) {
        FileChannel chan = fIS.getChannel();

        /* Note: this cast limits us to 2GB files - this shouldn't
         be a problem, but if it were we could use FileChannel#map
         and call Hawk.Client#registerModels one file at a time. */
        ByteBuffer buf = ByteBuffer.allocate((int) chan.size());
        chan.read(buf);
        buf.flip();/*from ww w .j a  va2  s  .c  o  m*/

        File mmFile = new File();
        mmFile.name = rawFile.getName();
        mmFile.contents = buf;
        return mmFile;
    }
}

From source file:ValidateLicenseHeaders.java

/**
 * Add the default jboss lgpl header//w w  w. j  a v  a 2  s .c om
 */
static void addDefaultHeader(File javaFile) throws IOException {
    if (addDefaultHeader) {
        FileInputStream fis = new FileInputStream(javaFile);
        FileChannel fc = fis.getChannel();
        int size = (int) fc.size();
        ByteBuffer contents = ByteBuffer.allocate(size);
        fc.read(contents);
        fis.close();

        ByteBuffer hdr = ByteBuffer.wrap(DEFAULT_HEADER.getBytes());
        FileOutputStream fos = new FileOutputStream(javaFile);
        fos.write(hdr.array());
        fos.write(contents.array());
        fos.close();
    }

    noheaders.add(javaFile);
}

From source file:password.pwm.util.secure.SecureEngine.java

public static String hash(final File file, final PwmHashAlgorithm hashAlgorithm)
        throws IOException, PwmUnrecoverableException {
    FileInputStream fileInputStream = null;
    try {// w  ww. j  a v a2 s .  c o m
        final MessageDigest messageDigest = MessageDigest.getInstance(hashAlgorithm.getAlgName());
        fileInputStream = new FileInputStream(file);
        final FileChannel fileChannel = fileInputStream.getChannel();
        final ByteBuffer byteBuffer = ByteBuffer.allocateDirect(1024 * 8);

        while (fileChannel.read(byteBuffer) > 0) {
            byteBuffer.flip();
            messageDigest.update(byteBuffer);
            byteBuffer.clear();
        }

        return JavaHelper.byteArrayToHexString(messageDigest.digest());

    } catch (NoSuchAlgorithmException | IOException e) {
        final String errorMsg = "unexpected error during file hash operation: " + e.getMessage();
        final ErrorInformation errorInformation = new ErrorInformation(PwmError.ERROR_CRYPT_ERROR, errorMsg);
        throw new PwmUnrecoverableException(errorInformation);
    } finally {
        IOUtils.closeQuietly(fileInputStream);
    }
}

From source file:ja.lingo.engine.util.EngineFiles.java

private static void appendFile(String fileName, FileOutputStream fos, boolean prependWithLength)
        throws IOException {
    FileInputStream fis = new FileInputStream(fileName);
    FileChannel fic = fis.getChannel();
    FileChannel foc = fos.getChannel();

    ByteBuffer buffer = ByteBuffer.allocate(COPY_BUFFER_SIZE);

    // put header: length (1 int = 4 bytes)
    if (prependWithLength) {
        buffer.putInt((int) new File(fileName).length());
    }//w w w .  j a  v a 2 s.  co  m

    // put body
    do {
        buffer.flip();
        foc.write(buffer);
        buffer.clear();
    } while (fic.read(buffer) != -1);
    fic.close();
    // NOTE: do not close 'foc'

    Files.delete(fileName);
}

From source file:ja.centre.util.io.Files.java

public static void copy(String source, String destination) throws IOException {
    FileInputStream fis = null;//from   w w  w  . j  ava  2s  .c  om
    FileOutputStream fos = null;
    try {
        fis = new FileInputStream(source);
        fos = new FileOutputStream(destination);

        FileChannel fic = null;
        FileChannel foc = null;
        try {
            fic = fis.getChannel();
            foc = fos.getChannel();

            ByteBuffer buffer = ByteBuffer.allocate(COPY_BUFFER_SIZE);
            do {
                buffer.flip();
                foc.write(buffer);
                buffer.clear();
            } while (fic.read(buffer) != -1);
        } finally {
            closeQuietly(fic);
            closeQuietly(foc);
        }
    } finally {
        closeQuietly(fis);
        closeQuietly(fos);
    }
}

From source file:com.igormaznitsa.jcp.utils.PreprocessorUtils.java

@Nonnull
public static byte[] readFileAsByteArray(@Nonnull final File file) throws IOException {
    checkFile(file);/*www. ja  va2s. c  o m*/

    int len = (int) file.length();

    final ByteBuffer buffer = ByteBuffer.allocate(len);
    final FileChannel inChannel = new FileInputStream(file).getChannel();

    try {
        while (len > 0) {
            final int read = inChannel.read(buffer);
            if (read < 0) {
                throw new IOException("Can't read whole file [" + getFilePath(file) + '\'');
            }
            len -= read;
        }
    } finally {
        IOUtils.closeQuietly(inChannel);
    }

    return buffer.array();
}

From source file:jext2.Superblock.java

/**
 * Read superblock using a FileChannel. This is intended for testing and code
 * that just needs the superblock not any file system access.
 *//*from   ww  w .  j a  va2 s  .  c o  m*/
public static Superblock fromFileChannel(FileChannel chan) throws IoError {

    Superblock sb = new Superblock(-1);
    ByteBuffer buf = ByteBuffer.allocate(Constants.EXT2_MIN_BLOCK_SIZE);
    try {
        chan.position(1024);
        chan.read(buf);
    } catch (IOException e) {
        throw new IoError();
    }
    sb.read(buf);

    Superblock.instance = sb;
    return sb;
}

From source file:org.cloudata.core.commitlog.pipe.CommitLogFileChannel.java

public static long readLastIndex(FileChannel ch) throws IOException {
    ByteBuffer buf = ByteBuffer.allocate(Long.SIZE / 8);
    long chSize = ch.size();

    if (chSize > 0) {
        ch.position(chSize > (Long.SIZE / 8) ? chSize - (Long.SIZE / 8) : 0);
        ch.read(buf);
        buf.flip();/*  w  ww. jav a  2 s  . c om*/
        return buf.getLong();
    } else {
        return 0;
    }
}

From source file:me.carpela.network.pt.cracker.tools.ttorrent.Torrent.java

private static String hashFiles(List<File> files, int pieceLenght)
        throws InterruptedException, IOException, NoSuchAlgorithmException {
    int threads = getHashingThreadsCount();
    ExecutorService executor = Executors.newFixedThreadPool(threads);
    ByteBuffer buffer = ByteBuffer.allocate(pieceLenght);
    List<Future<String>> results = new LinkedList<Future<String>>();
    StringBuilder hashes = new StringBuilder();

    long length = 0L;
    int pieces = 0;

    long start = System.nanoTime();
    for (File file : files) {

        length += file.length();//from  www  . j  av a  2  s.c  o  m

        FileInputStream fis = new FileInputStream(file);
        FileChannel channel = fis.getChannel();
        int step = 10;

        try {
            while (channel.read(buffer) > 0) {
                if (buffer.remaining() == 0) {
                    buffer.clear();
                    results.add(executor.submit(new CallableChunkHasher(buffer)));
                }

                if (results.size() >= threads) {
                    pieces += accumulateHashes(hashes, results);
                }

                if (channel.position() / (double) channel.size() * 100f > step) {
                    step += 10;
                }
            }
        } finally {
            channel.close();
            fis.close();
        }
    }

    // Hash the last bit, if any
    if (buffer.position() > 0) {
        buffer.limit(buffer.position());
        buffer.position(0);
        results.add(executor.submit(new CallableChunkHasher(buffer)));
    }

    pieces += accumulateHashes(hashes, results);

    // Request orderly executor shutdown and wait for hashing tasks to
    // complete.
    executor.shutdown();
    while (!executor.isTerminated()) {
        Thread.sleep(10);
    }
    long elapsed = System.nanoTime() - start;

    int expectedPieces = (int) (Math.ceil((double) length / pieceLenght));
    return hashes.toString();
}

From source file:Main.java

public static boolean fileCopy(File srcFile, File dstFile) {
    int length = 1048891;
    FileChannel inC = null;
    FileChannel outC = null;/* ww  w.ja  v  a  2  s.com*/
    try {
        FileInputStream in = new FileInputStream(srcFile);
        FileOutputStream out = new FileOutputStream(dstFile);
        inC = in.getChannel();
        outC = out.getChannel();
        ByteBuffer b = null;
        while (inC.position() < inC.size()) {
            if ((inC.size() - inC.position()) < length) {
                length = (int) (inC.size() - inC.position());
            } else {
                length = 1048891;
            }
            b = ByteBuffer.allocateDirect(length);
            inC.read(b);
            b.flip();
            outC.write(b);
            outC.force(false);
        }

        return true;
    } catch (IOException e) {
        e.printStackTrace();
        return false;
    } finally {
        try {
            if (inC != null && inC.isOpen()) {
                inC.close();
            }
            if (outC != null && outC.isOpen()) {
                outC.close();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}