title: Checking input type...how?
body: <p>I have the following method:</p>
  
  <pre><code>public void addStudent(){
  
      String fName, lName;
      double mGrade, fGrade;
      System.out.print("\nEnter first name: ");
      Scanner in = new Scanner(System.in);
      fName = in.nextLine();
      System.out.print("\nEnter last name: ");
      lName = in.nextLine();
      System.out.print("\nEnter midterm grade: ");
      mGrade = in.nextDouble();
      System.out.print("\nEnter final grade: ");
      fGrade = in.nextDouble();
      Student toAdd = new Student(fName, lName, mGrade, fGrade);
      students.add(toAdd);
      System.out.println("\nStudent record added.\n");
      System.out.println(students.size());
  }
  </code></pre>
  
  <p>How can I check if the user typed in something other than an integer for midterm grade and final grade? And if they entered a non-integer,  I want the method to just request the user type in that value again. I'm guessing I'll have to use a do-while loop. But I don't don't know how to check the type...</p>
  
  <p>Thanks!</p>