Endian converter java

EndianConverter.java

public static void endianConverter(byte[] buffer, int length) {
	if (buffer.length % length != 0 || length % 2 != 0) {
		throw new IllegalStateException();
	}
	for (int index = 0; index < buffer.length; index += length) {
		for (int endianIndex = 0; endianIndex < length / 2; endianIndex++) {
			final byte temp = buffer[index + endianIndex];
			buffer[index + endianIndex] = buffer[index + length - endianIndex - 1];
			buffer[index + length - endianIndex - 1] = temp;
		}
	}
}