package com.baeldung.maths; import org.junit.Assert; import org.junit.Test; import java.math.BigInteger; public class BigIntegerImplUnitTest { @Test public void givenBigIntegerNumbers_whenAddedTogether_thenGetExpectedResult() { BigInteger numStarsMilkyWay = new BigInteger("8731409320171337804361260816606476"); BigInteger numStarsAndromeda = new BigInteger("5379309320171337804361260816606476"); BigInteger totalStars = numStarsMilkyWay.add(numStarsAndromeda); BigInteger result = new BigInteger("14110718640342675608722521633212952"); Assert.assertEquals(result, totalStars); } }