title: The method is undefined for the type (Array List) Java
body: <p>I'm trying to implement interface methods in separate classes.
  I created two interfaces to calculate Tax and PRSI for FullTimeEmployee and PartTimeEmployee. I implemented the interfaces and extended each class from a class called Employee. 
  I created a new class to implement the methods the class is called Emplyee test I tried to group the FulltimeEmployee as an object into a array list.
  I'm getting the method is undefined for this type when I try to implement the methods from it's class.
  I spent quite a while trying to figure out the cause of the problem but I can't find any. Any help would be greatly appreciated.</p>
  
  <p>I included screen shots to highlight the issue. I know code is preferred, but I decided to show you all my classes as the problem can be lying in a other class.</p>
  
  <pre><code>import java.util.*;
   public class EmployeeTest  
  { 
      public static void main(String[] args){  
  
          ArrayList&lt;FullTimeEmployee&gt; empList = new ArrayList&lt;FullTimeEmployee&gt;();
  
          empList.add(new FullTimeEmployee("Adam", "Male","344667", 20000)); 
  
          empList.display();  
  
          empList.putHoursWorked(25);  
          empList.paySlip(); 
  
  
  
      }  
  
  }  
  </code></pre>