how to use integer in java enum

Question

Is there any way to keep straight integer in Java Enum ?

example: i am working on a Restaurant management system. i want to know what quantity of unit of any food a customer will order (e.g 1,2,5 etc.)

so i added a combo box in my GUI where list of units will be shown as : 1, 2, 3 etc. Now, Java Enum does not allowing me to write the code like this:

   public enum UnitEnum {
      1,2,3,4,5;
   }

What least i can do is writing it as:

   public enum UnitEnum {
      _1,_2,_3,_4,_5;
   }

but it is very much odd looking. Is there any way to make it look like the first one ? ( where there is no under score ).

No, there is not. Names must start with eiter a character, a $ or an _. The question is: why not write them: ONE, TWO,...? — Turing85
– Turing85, Commented Nov 12, 2015 at 14:02
it's just for saving time :p see, one, two, three etc. takes so many letters to type. — Shamin Asfaq
– Shamin Asfaq, Commented Nov 12, 2015 at 14:05
Do you have to use an an enum? Why not Collections.unmodifiableSet(new TreeSet<Integer>(Arrays.asList(1, 2, 5)))? — VGR
– VGR, Commented Nov 12, 2015 at 14:28

thegauravmahawar · Accepted Answer · 2015-11-12 14:10:23Z

6

You can do:

public enum UnitEnum {
  ONE(1),
  TWO(2),
  THREE(3),
  FOUR(4),
  FIVE(5);

  public final int quantity;

  UnitEnum(int q) {
     this.quantity = q;
  }

  public int getQuantity() { return this.quantity; }
}

edited Nov 12, 2015 at 14:10

answered Nov 12, 2015 at 14:03

thegauravmahawar

2,8213 gold badges17 silver badges25 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

Joop Eggen Over a year ago

And display the quantity in the combobox. private UnitEnum(int q) { quantity = q; } you assumed trivial.

Shamin Asfaq Over a year ago

i appreciate. it says constructor UnitEnum in enum UnitEnum cannot be applied to given types. required: no argument found: int reason: actual and formal argument lists differ in length.

dounyy Over a year ago

Why not using ordinal() here instead of defining the field quantity?

Felix Gerber · Accepted Answer · 2015-11-12 14:10:53Z

0

Here is an little tutorial about enums.

The way I would choose for your Problem is something like:

//Your enum
public enum UnitEnum{ONE, TWO, THREE, FOUR, FIVE};
//Using your enum
myENUM = 1; //compilation error  
myENUM = UnitEnum.ONE // works

answered Nov 12, 2015 at 14:10

Felix Gerber

1,6494 gold badges32 silver badges40 bronze badges

Comments

Joop Eggen · Accepted Answer · 2015-11-12 14:18:08Z

0

enum CheeseNuggets { X6, X9 }? Maybe not use an enum, but a class wrapping int[].

public class Ints {
    public final int[] values;

    public Ints(int... values) {
        this.values = Arrays.copyOf(values, values.length);
    }
}

answered Nov 12, 2015 at 14:18

Joop Eggen

110k8 gold badges89 silver badges142 bronze badges

Collectives™ on Stack Overflow

how to use integer in java enum

3 Answers 3

3 Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

3 Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related