Example usage for java.nio ByteBuffer allocate

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:Main.java

/**
 * Converts a given integer to byte, in little endian
 * @param i An integer to be converted to byte
 * @return A byte array stores byte representation of given integer
 *//* w ww  . j a  v a 2  s. c  om*/
public static byte[] intToByte(int i) {
    ByteBuffer b = ByteBuffer.allocate(4);
    b.order(ByteOrder.LITTLE_ENDIAN);
    b.putInt(i);
    byte buf[] = b.array();
    return buf;
}

From source file:Main.java

/**
 * convert int to byte array//from w  w w .j  a v  a2s.c  o m
 * 
 * @param value
 *            integer value
 * @return byte array
 */
public static byte[] convertIntToByte(int value) {
    byte[] temp = new byte[4];
    byte[] result = ByteBuffer.allocate(4).putInt(value).array();
    temp[0] = result[3];
    temp[1] = result[2];
    temp[2] = result[1];
    temp[3] = result[0];
    return temp;
}

From source file:Main.java

/**
 * bytes tp chars/*from w w  w  . ja v a  2 s.  c  o m*/
 * 
 * @param bytes
 * @return
 */
public static char[] getChars(byte[] bytes) {
    Charset cs = Charset.forName("UTF-8");
    ByteBuffer bb = ByteBuffer.allocate(bytes.length);
    bb.put(bytes);
    bb.flip();
    CharBuffer cb = cs.decode(bb);
    return cb.array();
}

From source file:Main.java

public static ByteBuffer cloneByteBuffer(final ByteBuffer original) {
    // Create clone with same capacity as original.
    final ByteBuffer clone = (original.isDirect()) ? ByteBuffer.allocateDirect(original.capacity())
            : ByteBuffer.allocate(original.capacity());

    // Create a read-only copy of the original.
    // This allows reading from the original without modifying it.
    final ByteBuffer readOnlyCopy = original.asReadOnlyBuffer();

    // Flip and read from the original.
    readOnlyCopy.flip();//from   ww w .jav a 2s.  co m
    clone.put(readOnlyCopy);
    clone.position(original.position());
    clone.limit(original.limit());
    clone.order(original.order());
    return clone;
}

From source file:Main.java

/**
 * Converts bitmap to the byte array without compression
 * @param bitmap source bitmap//  www  .j  a  va 2  s.c  o  m
 * @return result byte array
 */
public static byte[] convertBitmapToByteArrayUncompressed(Bitmap bitmap) {
    ByteBuffer byteBuffer = ByteBuffer.allocate(bitmap.getByteCount());
    bitmap.copyPixelsToBuffer(byteBuffer);
    byteBuffer.rewind();
    return byteBuffer.array();
}

From source file:Main.java

/**
 * Create a message from an array, first field of the message is the size of the array
 * @param array/*from   www .ja  va  2 s  .com*/
 * @return
 */
public static byte[] createMessageFromArray(ArrayList<byte[]> array) {

    byte[] buffer1 = new byte[4];
    System.arraycopy(ByteBuffer.allocate(4).putInt(array.size()).array(), 0, buffer1, 0, 4);

    byte[] buffer2 = compileMessages(array);

    return concatenateMessages(buffer1, buffer2);
}

From source file:Main.java

public static byte[] uuidToBytes(String uuidStr) {
    UUID uuid = stringToUuid(uuidStr);

    ByteBuffer bb = ByteBuffer.allocate(16);
    bb.order(ByteOrder.LITTLE_ENDIAN);
    bb.putLong(uuid.getLeastSignificantBits());
    bb.putLong(uuid.getMostSignificantBits());
    return bb.array();
}

From source file:Main.java

public static byte[] bitmapToBytes(Bitmap b) {
    //calculate how many bytes our image consists of.
    int bytes = b.getByteCount();
    //or we can calculate bytes this way. Use a different value than 4 if you don't use 32bit images.
    //int bytes = b.getWidth()*b.getHeight()*4;

    ByteBuffer buffer = ByteBuffer.allocate(bytes); //Create a new buffer
    b.copyPixelsToBuffer(buffer); //Move the byte data to the buffer

    byte[] array = buffer.array();

    return array;
}

From source file:Main.java

public static byte[] toArray(int value) {
    ByteBuffer buffer = ByteBuffer.allocate(4);
    buffer.order(ByteOrder.LITTLE_ENDIAN);
    buffer.putInt(value);//ww  w.  ja va  2  s  .  com
    return buffer.array();
}

From source file:Main.java

public static byte[] createDigest(String passcode, long t1, double q1)
        throws IOException, NoSuchAlgorithmException {
    MessageDigest md = MessageDigest.getInstance("SHA");
    md.update(passcode.getBytes());// w w  w  . j ava2  s . co m
    ByteBuffer bb = ByteBuffer.allocate(16); //8 bytes for long and double each
    bb.putLong(t1);
    bb.putDouble(q1);
    md.update(bb);
    return md.digest();
}