public class packet {

	public int getByte(int start,byte b[]) {
		byte mb = b[start];
        	return mb<0 ? (int)mb + 256 : (int)mb;       
	}
 
	public int getWord(int start,byte b[]) {
		return (getByte(start,b) << 8) | getByte(start+1,b);
	}
   
	public long getLong(int start,byte b[]) {
		return ((long)getByte(start,b) << 24) | ((long)getByte(start+1,b) << 16) | ((long)getByte(start+2,b) << 8) | (long)getByte(start+3,b);
	}

}