Java Int64 Convert int64ToByteArray(long value, int size)

Description

Converts an int64 into a byte array with a maximum size of 8.

License

Open Source License

Declaration

public static byte[] int64ToByteArray(long value, int size) 

Method Source Code

//package com.java2s;
/**/*from  w  ww  .  j a va  2  s.c o m*/
* 
* Copyright (C) 2004-2008 FhG Fokus
*
* This file is part of the FhG Fokus UPnP stack - an open source UPnP implementation
* with some additional features
*
* You can redistribute the FhG Fokus UPnP stack and/or modify it
* under the terms of the GNU General Public License Version 3 as published by
* the Free Software Foundation.
*
* For a license to use the FhG Fokus UPnP stack software under conditions
* other than those described here, or to purchase support for this
* software, please contact Fraunhofer FOKUS by e-mail at the following
* addresses:
*   upnpstack@fokus.fraunhofer.de
*
* The FhG Fokus UPnP stack 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 this program; if not, see <http://www.gnu.org/licenses/>
* or write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/

public class Main {
    /**
     * Converts an int64 into a byte array with a maximum size of 8. Leading digits are filled with zero.
     */
    public static byte[] int64ToByteArray(long value, int size) {
        if (size > 8) {
            return null;
        }
        byte[] tempResult = new byte[8];
        clear(tempResult);

        int offset = 7;
        while (value != 0 && offset != -1) {
            tempResult[offset] = (byte) (value & 0xFF);
            value = value >> 8;
            offset--;
        }
        byte[] result = new byte[size];
        System.arraycopy(tempResult, 8 - size, result, 0, size);

        return result;
    }

    /** Fills a byte array with 0. */
    public static void clear(byte[] array) {
        fill(array, (byte) 0);
    }

    /** Fills a byte array with a value. */
    public static void fill(byte[] array, byte value) {
        if (array == null) {
            return;
        }
        for (int i = 0; i < array.length; i++) {
            array[i] = value;
        }
    }
}

Related

1. int64(Object value)
2. Int642Bytes(long sour)
3. int64_to_buf(byte buf[], int pos, long value)
4. int64d(byte[] buf, int off)
5. int64toInt32(long key)