title: Java date time subtraction
body: <p>String date1 = "2020/05/08 16.38.37"
  String date2 = "2020/04/08 20.18.10"</p>
  
  <p>I wish to subtract complete date1 with complete date2 (date and time both included) and get the result in hours  in java . 
  How to proceed ?</p>