Java using enum with switch statement

by

The part you’re missing is converting from the integer to the type-safe enum. Java will not do it automatically. There’s a couple of ways you can go about this:

  1. Use a list of static final ints rather than a type-safe enum and switch on the int value you receive (this is the pre-Java 5 approach)
  2. Switch on either a specified id value (as described by heneryville) or the ordinal value of the enum values; i.e. guideView.GUIDE_VIEW_SEVEN_DAY.ordinal()

  3. Determine the enum value represented by the int value and then switch on the enum value.

    enum GuideView {
    SEVEN_DAY,
    NOW_SHOWING,
    ALL_TIMESLOTS
}

// Working on the assumption that your int value is 
// the ordinal value of the items in your enum
public void onClick(DialogInterface dialog, int which) {
    // do your own bounds checking
    GuideView whichView = GuideView.values()[which];
    switch (whichView) {
        case SEVEN_DAY:
            ...
            break;
        case NOW_SHOWING:
            ...
            break;
    }
}

    You may find it more helpful / less error prone to write a custom valueOf implementation that takes your integer values as an argument to resolve the appropriate enum value and lets you centralize your bounds checking.

More Related Contents:

  1. Why is default required for a switch on an enum?
  2. Switch over type in java
  3. Maximum number of enum elements in Java
  4. New to Java and having issues writing and example
  5. How to get an enum value from a string value in Java
  6. Why do we need break after case statements?
  7. Switch without break
  8. Map enum in JPA with fixed values?
  9. How can I lookup a Java enum from its String value?
  10. Coding Conventions – Naming Enums
  11. Convert from enum ordinal to enum type
  12. Compile and execute a JDK preview feature with Maven
  13. Enum in Java. Advantages?
  14. Getting enum associated with int value
  15. What’s the best way to implement `next` and `previous` on an enum type?
  16. Java switch statement multiple cases
  17. How to ensure completeness in an enum switch at compile time?
  18. Use Enum type as a value parameter for @RolesAllowed-Annotation
  19. Enum in Hibernate, persisting as an enum
  20. How thread-safe is enum in java?
  21. switch expression can’t be float, double or boolean
  22. Java Enums: Two enum types, each containing references to each other?
  23. Kotlin ‘when’ statement vs Java ‘switch’
  24. Lambdas in the classical Operation enum example
  25. What are switch expressions and how are they different from switch statements?
  26. Java: Check if enum contains a given string?
  27. Using nested enum types in Java
  28. Using Integer in Switch Statement
  29. Why Java does not allow overriding equals(Object) in an Enum?
  30. Java Enum getDeclaringClass vs getClass

Leave a Comment