Here you can find the source of chop(BigInteger in, int bits)
private static BigInteger[] chop(BigInteger in, int bits)
//package com.java2s; //License from project: Open Source License import java.math.BigInteger; public class Main { private static BigInteger[] chop(BigInteger in, int bits) { BigInteger left = in.shiftRight(bits); BigInteger right = in.subtract(left.shiftLeft(bits)); return new BigInteger[] { left, right }; }//ww w .j ava 2 s . c om }