Non-Static method cannot be referenced from a static context with methods and variables

Question

In writing a BookStoreApplication which uses Book  Tape  and CD classes to create objects  Although unfinished  the application class should create new BookStoreItems  which are Book  Tape  and CD  They inherit from the BookStoreItems class  In this application class I keep getting the error   error  non-static method printMenu   cannot be referenced from a static context error  non-static method getUserChoice   cannot be referenced from a static context error  non-static variable input cannot be referenced from a static context   I ve changed it to be static and then not to be static  yet I continue to get this error     import java util Scanner   public class BookStoreApp2          constants for options     static final int ADD BOOK   0      static final int ADD TAPE   1      static final int ADD CD   2      static final int QUIT   -1       Scanner input   new Scanner  System in        public static void main String   args              BookStoreItem   item   declaring array          item   new BookStoreItem 10    initializing array          int itemType   -1           printMenu            getUserChoice             for  int i   0  i  lt  item length  i                 System out print   n    i     tEnter 0 for Book  1 for Tape  2 for CD                  itemType   input nextInt                 switch  itemType                    case 0                      item i    new Book                        break                  case 1                      item i    new Tape                        break                  case 2                      item i    new CD                        break                  default                       System out println   nInvalid choice                    end of switch statement             end of for loop          for  int i   0  i  lt  item length  i                  System out println   nAnimal      i                       System out println   n tTitle      item i  getTitle       polymorphic because they can operate on separate objects             System out println   n tAuthor      item i  getAuthor                end of for          end of main method     PRINT MENU----------------------------------------------------------       public void printMenu            System out println   nPress             System out println   t    ADD BOOK     tTo add a book to the book store  n            System out println   t    ADD TAPE     tTo add a tape to the book store  n            System out println   t    ADD CD     tTo add a CD to the book store  n            System out println   t    QUIT     tTo exit n            ---------------------------------------------------------------------   GET USER CHOICE------------------------------------------------------       public int getUserChoice             int choice               System out print  Please enter your choice              choice   input nextInt             return choice         end of getUserChoice   ----------------------------------------------------------------------     end class

User · Answer

You should place Scanner input   new Scanner  System in   into the main method rather than creating the input object outside

User · Answer

Merely for the purposes of making your program work  take the contents of your main   method and put them in a constructor   public BookStoreApp2           Put contents of main method here     Then  in your main   method   Do this   public void main  String   args       new BookStoreApp2

User · Answer

You need to make both your method - printMenu   and getUserChoice   static  as you are directly invoking them from your static main method  without creating an instance of the class  those methods are defined in  And you cannot invoke a non-static method without any reference to an instance of the class they are defined in   Alternatively you can change the method invocation part to   BookStoreApp2 bookStoreApp   new BookStoreApp2    bookStoreApp printMenu    bookStoreApp getUserChoice

User · Answer

You can either  1  Declare printMenu    getUserchoice   and input as static  OR  2  If you want to design it better  move the logic from your main into a separate instance method  And then from the main create a new instance of your class and call your instance method s

[java] Non-Static method cannot be referenced from a static context with methods and variables

Examples related to java

Examples related to methods

Examples related to static

Examples related to compiler-errors