How do I initialize and increment a byte array in Java?

Question

I need to increment a 32 bit value each time I enter a certain loop. However, eventually it must be in a byte array (byte[]) form. What is the best way to go about it?

Option 1:

byte[] count = new byte[4];
//some way to initialize and increment byte[]

Option 2:

int count=0;
count++;
//some way to convert int to byte

Option 3: ??

Answer 1

You would convert your int to byte[] as follows:

ByteBuffer b = ByteBuffer.allocate(4);
//b.order(ByteOrder.BIG_ENDIAN); // optional, the initial order of a byte buffer is always BIG_ENDIAN.
b.putInt(0xAABBCCDD);

byte[] result = b.array();  

source: Convert integer into byte array (Java)

Now comes the increment part. You can increment your integer the same way you would do. using ++ or whatever the need be. Then, clear the ByteBuffer, put in the number again, flip() the buffer and get the array