hey i need a help with this question

Write a structured program that can accept two integer numbers up to 40 digits and perform the followings:

1. Add the two numbers and display the result.

2. The result number should be separated by commas. For example

If inputs are:

Number1: 236598745632

Number2: 2453254365546764765

The output should be:

236,598,745,632 +

2,453,254,365,546,764,765

-------------------------------------

2,453,254,602,145,510,397

i just want to do it in basic java

Notes:

You must read the two input numbers as string objects, then verify if the input is correct (i.e. all digit characters).

You may assume that your program only works for positive integer numbers.

You cannot use any of BigDecimal / BigInteger / double / long / int types for your calculations.