为什么我不能在这里创建抽象类的对象并且我得到了非静态变量的错误，这不能从静态上下文中引用

执行此代码时出现错误。为什么我得到不能从静态上下文中引用的非静态变量？

  class javatest{
     public abstract class Employee {
            public abstract void names();

                 }

      public class Banani extends Employee{
            @Override
            public void names(){
               System.out.println("I am at Banani.");
             }
          }

       public class Shyamoli extends Employee{
              @Override
              public void names(){
              System.out.println("I am at Shyamoli");
       }
   }

        public static void main(String[] args){


           Employee south = new Banani();
           Employee north = new Shyamoli();
           north.names();
           south.names();
        }
       }