title: Add integer in 27 char hex string in java
body: <p>I have a hex String 240300000800000000000000004.
  I want to add integer in this hex code and get back hex code in java.</p>
  
  <p>As java does not support this muck length of value, so how do we do this?</p>
  
  <p>Thanks 
  Abhishek</p>