Example usage for java.nio ByteBuffer allocate

List of usage examples for java.nio ByteBuffer allocate

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Introduction

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

Prototype

public static ByteBuffer allocate(int capacity)

Source Link

Document

Creates a byte buffer based on a newly allocated byte array.

Usage

From source file:com.sm.store.Utils.java

public static byte[] putInt(int k) {
    return ByteBuffer.allocate(4).putInt(k).array();
}

From source file:Main.java

public static long getCommentLength(final FileChannel fileChannel) throws IOException {
    // End of central directory record (EOCD)
    // Offset    Bytes     Description[23]
    // 0           4       End of central directory signature = 0x06054b50
    // 4           2       Number of this disk
    // 6           2       Disk where central directory starts
    // 8           2       Number of central directory records on this disk
    // 10          2       Total number of central directory records
    // 12          4       Size of central directory (bytes)
    // 16          4       Offset of start of central directory, relative to start of archive
    // 20          2       Comment length (n)
    // 22          n       Comment
    // For a zip with no archive comment, the
    // end-of-central-directory record will be 22 bytes long, so
    // we expect to find the EOCD marker 22 bytes from the end.

    final long archiveSize = fileChannel.size();
    if (archiveSize < ZIP_EOCD_REC_MIN_SIZE) {
        throw new IOException("APK too small for ZIP End of Central Directory (EOCD) record");
    }/*from   www .  j av  a 2  s  . c om*/
    // ZIP End of Central Directory (EOCD) record is located at the very end of the ZIP archive.
    // The record can be identified by its 4-byte signature/magic which is located at the very
    // beginning of the record. A complication is that the record is variable-length because of
    // the comment field.
    // The algorithm for locating the ZIP EOCD record is as follows. We search backwards from
    // end of the buffer for the EOCD record signature. Whenever we find a signature, we check
    // the candidate record's comment length is such that the remainder of the record takes up
    // exactly the remaining bytes in the buffer. The search is bounded because the maximum
    // size of the comment field is 65535 bytes because the field is an unsigned 16-bit number.
    final long maxCommentLength = Math.min(archiveSize - ZIP_EOCD_REC_MIN_SIZE, UINT16_MAX_VALUE);
    final long eocdWithEmptyCommentStartPosition = archiveSize - ZIP_EOCD_REC_MIN_SIZE;
    for (int expectedCommentLength = 0; expectedCommentLength <= maxCommentLength; expectedCommentLength++) {
        final long eocdStartPos = eocdWithEmptyCommentStartPosition - expectedCommentLength;

        final ByteBuffer byteBuffer = ByteBuffer.allocate(4);
        fileChannel.position(eocdStartPos);
        fileChannel.read(byteBuffer);
        byteBuffer.order(ByteOrder.LITTLE_ENDIAN);

        if (byteBuffer.getInt(0) == ZIP_EOCD_REC_SIG) {
            final ByteBuffer commentLengthByteBuffer = ByteBuffer.allocate(2);
            fileChannel.position(eocdStartPos + ZIP_EOCD_COMMENT_LENGTH_FIELD_OFFSET);
            fileChannel.read(commentLengthByteBuffer);
            commentLengthByteBuffer.order(ByteOrder.LITTLE_ENDIAN);

            final int actualCommentLength = commentLengthByteBuffer.getShort(0);
            if (actualCommentLength == expectedCommentLength) {
                return actualCommentLength;
            }
        }
    }
    throw new IOException("ZIP End of Central Directory (EOCD) record not found");
}

From source file:com.fujitsu.dc.test.jersey.bar.BarInstallTestUtils.java

/**
 * bar?.//  w  w w .  ja  va2s . c o  m
 * @param barFile bar?
 * @return ??bar
 */
public static byte[] readBarFile(File barFile) {
    InputStream is = ClassLoader.getSystemResourceAsStream(barFile.getPath());
    ByteBuffer buff = ByteBuffer.allocate(READ_BUFFER_SIZE);
    log.debug(String.valueOf(buff.capacity()));
    try {
        byte[] bbuf = new byte[SIZE_KB];
        int size;
        while ((size = is.read(bbuf)) != -1) {
            buff.put(bbuf, 0, size);
        }
    } catch (IOException e) {
        throw new RuntimeException("failed to load bar file:" + barFile.getPath(), e);
    } finally {
        try {
            is.close();
        } catch (IOException e) {
            throw new RuntimeException("failed to close bar file:" + barFile.getPath(), e);
        }
    }
    int size = buff.position();
    buff.flip();
    byte[] retv = new byte[size];
    buff.get(retv, 0, size);
    return retv;
}

From source file:com.linkedin.pinot.perf.BenchmarkFileRead.java

@Setup
public void loadData() {
    try {//from ww w .  ja v a2s.  c o m
        file = new File("/Users/jfim/index_dir/sTest_OFFLINE/sTest_0_0/daysSinceEpoch.sv.unsorted.fwd");
        raf = new RandomAccessFile(file, "rw");
        length = (int) file.length();
        byteBuffer = ByteBuffer.allocate(length);
        raf.getChannel().read(byteBuffer);
    } catch (IOException e) {
        throw new RuntimeException(e);
    }
}

From source file:com.datatorrent.contrib.hdht.HDHTWriterTest.java

public static Slice newKey(long bucketId, long sequenceId) {
    byte[] bytes = ByteBuffer.allocate(16).putLong(sequenceId).putLong(bucketId).array();
    return new Slice(bytes, 0, bytes.length);
}

From source file:jsave.Utils.java

public static int read_long(final RandomAccessFile raf) throws IOException {
    byte[] data = new byte[4];
    raf.read(data);/*  w  w  w.  ja  v  a 2 s  . c  om*/
    ByteBuffer bb = ByteBuffer.allocate(data.length);
    bb.put(data);
    return bb.getInt(0);
}

From source file:com.codeabovelab.dm.common.security.token.SignedTokenServiceBackend.java

@Override
public TokenData createToken(TokenConfiguration config) {
    final long creationTime = System.currentTimeMillis();

    byte[] serverSecret = computeServerSecretApplicableAt(creationTime);
    byte[] content = contentPack(creationTime, generateRandom(), serverSecret,
            Utf8.encode(pack(config.getUserName(), config.getDeviceHash())));

    byte[] sign = sign(content);
    ByteBuffer buffer = ByteBuffer.allocate(1 + sign.length + 1 + content.length);
    store(buffer, content);/*  w ww.j a  v  a2s.  c  o  m*/
    store(buffer, sign);
    String key = base32.encodeAsString(buffer.array());

    return new TokenDataImpl(creationTime, TokenUtils.getKeyWithTypeAndToken(TYPE, key), config.getUserName(),
            config.getDeviceHash());
}

From source file:com.github.neoio.net.message.staging.file.TestFileMessageStaging.java

@Test
public void test_tempWrite() {
    ByteBuffer buffer = ByteBuffer.allocate(1024);

    buffer.put("Hello World".getBytes());
    buffer.flip();//  w w  w .jav a  2s  . c o m
    staging.writeTempWriteBytes(buffer);
    Assert.assertTrue(staging.hasTempWriteBytes());

    buffer.clear();
    staging.readTempWriteBytes(buffer);
    Assert.assertEquals("Hello World",
            new String(ArrayUtils.subarray(buffer.array(), 0, "Hello World".getBytes().length)));
    staging.resetTempWriteBytes();

    Assert.assertFalse(staging.hasTempWriteBytes());
}

From source file:com.offbynull.peernetic.debug.actornetwork.messages.TransitMessage.java

/**
 * Constructs a {@link TransitMessage} object.
 * @param source source//from www .j  av a 2s.  c  o  m
 * @param destination destination
 * @param data contents
 * @param departTime time packet departed
 * @param duration duration the packet should stay in transit (before arriving)
 * @throws NullPointerException if any arguments are {@code null}
 * @throws IllegalArgumentException if {@code duration} is negative
 */
public TransitMessage(A source, A destination, ByteBuffer data, Instant departTime, Duration duration) {
    Validate.notNull(source);
    Validate.notNull(destination);
    Validate.notNull(data);
    Validate.notNull(departTime);
    Validate.notNull(duration);
    Validate.isTrue(!duration.isNegative());
    this.source = source;
    this.destination = destination;
    this.data = ByteBuffer.allocate(data.remaining());
    this.data.put(data);
    this.data.flip();
    this.departTime = departTime;
    this.duration = duration;
}

From source file:com.sm.store.Utils.java

public static byte[] putLong(long k) {
    return ByteBuffer.allocate(8).putLong(k).array();
}