Java Long to Byte Array long2byteArray(final long number, final int length, final boolean swapHalfWord)

Description

Converts a long number to a byte array Halfwords can be swapped by setting swapHalfWord=true.

License

Apache License

Parameter

Parameter	Description
number	the input long number to be converted
length	The length of the returned array
swapHalfWord	Swap halfwords ([0][1][2][3]->[1][0][3][2])

Exception

Parameter	Description
UnsupportedOperationException	if the length is not a positive multiple of two

Return

The long value

Declaration

static byte[] long2byteArray(final long number, final int length, final boolean swapHalfWord) 

Method Source Code

//package com.java2s;
//License from project: Apache License 

public class Main {
    /**//from   w  w  w. jav a 2s  .  co m
     * Converts a long number to a byte array
     * Halfwords can be swapped by setting swapHalfWord=true.
     *
     * @param number       the input long number to be converted
     * @param length       The length of the returned array
     * @param swapHalfWord Swap halfwords ([0][1][2][3]->[1][0][3][2])
     * @return The long value
     * @throws UnsupportedOperationException if the length is not a positive multiple of two
     */
    static byte[] long2byteArray(final long number, final int length, final boolean swapHalfWord) {
        byte[] ret = new byte[length];
        int pos = 0;
        long tmp_number = 0;

        if (length % 2 != 0 || length < 2) {
            throw new UnsupportedOperationException();
        }

        tmp_number = number;
        for (pos = length - 1; pos >= 0; pos--) {
            ret[pos] = (byte) (tmp_number & 0xFF);
            tmp_number >>= 8;
        }

        if (!swapHalfWord) {
            byte tmp = 0;
            for (pos = 0; pos < length; pos++) {
                tmp = ret[pos];
                ret[pos++] = ret[pos];
                ret[pos] = tmp;
            }
        }

        return ret;
    }
}

Related

1. long2byteArray(long k, byte b[], int off)
2. long2ByteArray(long l)
3. long2ByteArray(long srcValue, int len)
4. long2ByteLE(byte[] bytes, long value, int offset)