ByteUtils.java

package com.beowulfe.hap.impl.pairing;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.math.BigInteger;
import java.util.Arrays;

class ByteUtils {

	public static byte[] joinBytes(byte[]... piece) {
		int pos = 0;
		int length = 0;
		for(int i=0; i<piece.length; i++) {
			length += piece[i].length;
		}
		byte[] ret = new byte[length];
		for (int i=0; i<piece.length; i++) {
			System.arraycopy(piece[i], 0, ret, pos, piece[i].length);
			pos += piece[i].length;
		}
		return ret;
	}
	
	public static byte[] toByteArray(BigInteger i) {
		byte[] array = i.toByteArray();
		if (array[0] == 0) {
			array = Arrays.copyOfRange(array, 1, array.length);
		}
		return array;
	}
	
	public static void copyStream(InputStream input, OutputStream output, int length) throws IOException {
	    byte[] buffer = new byte[length];
	    int remaining = length;
	    int bytesRead;
	    while ((bytesRead = input.read(buffer, 0, remaining)) != -1 && remaining > 0)
	    {
	        output.write(buffer, 0, bytesRead);
	        remaining -= bytesRead;
	    }
	}
}