}
/**
- * Converts a long to 6 bytes array for mac addresses
- * @param addr
- * @return
+ * Converts a 6 bytes array into a long number MAC addresses.
+ *
+ * @param ba
+ * The 6 bytes long byte array.
+ * @return The long number.
+ * Zero is returned if {@code ba} is {@code null} or
+ * the length of it is not six.
*/
+ public static long byteArray6ToLong(byte[] ba) {
+ if (ba == null || ba.length != MACAddrLengthInBytes) {
+ return 0L;
+ }
+ long num = 0L;
+ int i = 0;
+ do {
+ num <<= NumBitsInAByte;
+ num |= 0xff & ba[i];
+ i++;
+ } while (i < MACAddrLengthInBytes);
+ return num;
+ }
+ /**
+ * Converts a long number to a 6 bytes array for MAC addresses.
+ *
+ * @param addr
+ * The long number.
+ * @return The byte array.
+ */
public static byte[] longToByteArray6(long addr){
- byte[] mac = new byte[6];
- for(int i = 0; i < 6; i++){
- mac[i] = (byte) (addr >> (i*8));
- }
+ byte[] mac = new byte[MACAddrLengthInBytes];
+ int i = MACAddrLengthInBytes - 1;
+ do {
+ mac[i] = (byte) addr;
+ addr >>>= NumBitsInAByte;
+ i--;
+ } while (i >= 0);
return mac;
}
-
/**
* Converts an integer number into a 4 bytes array
*