Example output: Enter the desired Fibonacci number n: 9 34 Enter the desired Fibonacci number n: bob Error: you must enter a number Enter the desired Fibonacci number n: -2 Error: -2 is not a positive number

1) Below is Java program to read a number from user, validate it and display its Fibonacci number.

• It imports scanner to read user inputs
• In main method of program
  • Create a scanner object to read user input
  • Ask user to enter a number
  • Validate the read number using try catch statement
    • Read integer
    • Check if number is positive
      • Call fibonacci function passing number n as parameter
      • Display the returned fibonacci number 
      •  
    • Else display it is not a positive number
  • On exception, display error message, Error. You must enter a number
• Define method to that calculates the fibonacci number using recursive approach 

2) Save program in Driver.java and run