Java Byte Array Create toByteArray(int[] data)

Description

Convenience method to transform an int[] array to a byte array for serialization.

License

Open Source License

Parameter

Parameter	Description
data	the int[] to convert

Return

the resulting byte[] 4 times in size (4 bytes per int)

Declaration

public static byte[] toByteArray(int[] data)

Method Source Code

//package com.java2s;
/*/*from   w ww  .  ja  v  a 2  s .  c om*/
 * This file is part of the LIRe project: http://www.semanticmetadata.net/lire
 * LIRe is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * LIRe is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with LIRe; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * We kindly ask you to refer the following paper in any publication mentioning Lire:
 *
 * Lux Mathias, Savvas A. Chatzichristofis. Lire: Lucene Image Retrieval ?
 * An Extensible Java CBIR Library. In proceedings of the 16th ACM International
 * Conference on Multimedia, pp. 1085-1088, Vancouver, Canada, 2008
 *
 * http://doi.acm.org/10.1145/1459359.1459577
 *
 * Copyright statement:
 * --------------------
 * (c) 2002-2011 by Mathias Lux (mathias@juggle.at)
 *     http://www.semanticmetadata.net/lire
 */

public class Main {
    /**
     * Convenience method to transform an int[] array to a byte array for serialization.
     *
     * @param data the int[] to convert
     * @return the resulting byte[] 4 times in size (4 bytes per int)
     */
    public static byte[] toByteArray(int[] data) {
        byte[] tmp, result = new byte[data.length * 4];
        for (int i = 0; i < data.length; i++) {
            tmp = toBytes(data[i]);
            System.arraycopy(tmp, 0, result, i * 4, 4);
        }
        return result;
    }

    /**
     * Convenience method for creating a byte array from a float array.
     *
     * @param data the input float array
     * @return a byte array for serialization.
     */
    public static byte[] toByteArray(float[] data) {
        byte[] tmp, result = new byte[data.length * 4];
        for (int i = 0; i < data.length; i++) {
            tmp = toBytes(data[i]);
            System.arraycopy(tmp, 0, result, i * 4, 4);
        }
        return result;
    }

    /**
     * Convenience method for creating a byte array from a double array.
     *
     * @param data the input float array
     * @return a byte array for serialization.
     */
    public static byte[] toByteArray(double[] data) {
        byte[] tmp, result = new byte[data.length * 8];
        for (int i = 0; i < data.length; i++) {
            tmp = toBytes(data[i]);
            System.arraycopy(tmp, 0, result, i * 8, 8);
        }
        return result;
    }

    /**
     * Converts an int to a byte array with 4 elements. Used to put ints into a byte[] payload in a convenient
     * and fast way by shifting without using streams (which is kind of slow). <br/>
     * Taken from http://www.daniweb.com/code/snippet216874.html
     *
     * @param data the int to convert
     * @return the resulting byte[] array
     * @see net.semanticmetadata.lire.utils.SerializationUtils#toInt(byte[])
     */
    public static byte[] toBytes(int data) {
        return new byte[] { (byte) ((data >> 24) & 0xff),
                (byte) ((data >> 16) & 0xff), (byte) ((data >> 8) & 0xff),
                (byte) ((data >> 0) & 0xff), };
    }

    /**
     * Converts a long to a byte[] array.<br/>
     * Taken from http://www.daniweb.com/software-development/java/code/216874
     *
     * @param data the long to convert
     * @return the resulting byte[] array
     * @see #toLong(byte[])
     */
    public static byte[] toBytes(long data) {
        return new byte[] { (byte) ((data >> 56) & 0xff),
                (byte) ((data >> 48) & 0xff), (byte) ((data >> 40) & 0xff),
                (byte) ((data >> 32) & 0xff), (byte) ((data >> 24) & 0xff),
                (byte) ((data >> 16) & 0xff), (byte) ((data >> 8) & 0xff),
                (byte) ((data >> 0) & 0xff), };
    }

    /**
     * Converts a float to a byte array with 4 elements. Used to put floats into a byte[] payload in a convenient
     * and fast way by shifting without using streams (which is kind of slow). Use
     * {@link net.semanticmetadata.lire.utils.SerializationUtils#toFloat(byte[])} to decode.
     *
     * @param data the float to convert
     * @return the resulting byte array
     * @see net.semanticmetadata.lire.utils.SerializationUtils#toFloat(byte[])
     */
    public static byte[] toBytes(float data) {
        return toBytes(Float.floatToRawIntBits(data));
    }

    /**
     * Converts a double to a byte array with 4 elements. Used to put doubles into a byte[] payload in a convenient
     * and fast way by shifting without using streams (which is kind of slow). Use
     * {@link net.semanticmetadata.lire.utils.SerializationUtils#toDouble(byte[])} to decode. Note that there is a loss
     * in precision as the double is converted to a float in the course of conversion.
     *
     * @param data the double to convert
     * @return the resulting byte array
     * @see net.semanticmetadata.lire.utils.SerializationUtils#toDouble(byte[])
     */
    public static byte[] toBytes(double data) {
        return toBytes(Double.doubleToLongBits(data));
    }
}

Java Byte Array Create toByteArray(int[] data)

Description

License

Parameter

Return

Declaration

Method Source Code

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