16.3. Exercises: Enum Practice¶

1. Fork and clone enumerable-planets.

2. Use the Get from Version Control option to open the project in IntelliJ.

3. In the project, navigate to the data package.

4. Create a new public enum called Planets.

   public enum Planets {
      // list the planets here.
      // Mercury, Venus, Earth, Mars, Jupiter,
      // Saturn, Uranus, Neptune
      // Don't forget to capitalization convention and enum
      // syntax to separate value and end the list
   }
   

5. Before adding any other fields to Planets, go to PlanetController and update the index handler to pass in a Model class argument (eg. Model model).

   Check your solution

6. Use .addAttribute to add the planet values to the model.

7. In templates/index, create a list element and use the template variable you have just defined in the controller to list all of the planet values on the page.

   Check your solution

8. Add a name field to the planets.

   1. Create a name property to display a non-capitalized version of each of the planet names.
   2. Add a constructor with the name field and a getter for the field.

9. Update the template to display the planet names.

   Check your solution

10. Back in the Planets enum, add a new field called yearLength.

    1. The value of each yearLength should be the number of earth days of a year on the given planet.
       1. Number of earth days on each planet:
          1. Mercury: 88
          2. Venus: 225
          3. Earth: 365
          4. Mars: 687
          5. Jupiter: 4333
          6. Saturn: 10759
          7. Uranus: 30687
          8. Neptune: 60200
    2. Update the constructor and add a getter for this field.

11. Change the index template to display a table of each planet name and its year in earth days.

    1. In templates/index, create a table element and add the appropriate bootstrap class.
    2. The table can be styled to your liking.
    3. Add a message to let the users know what data you are displaying with the yearLength field.

    Check your solution

12. If you wish, add another field to Planets. You can find plenty of information on NASA’s web site.

    1. Update the enum with the new field, including changing the constructor and adding a getter method.
    2. Add the field to display in the table, with a message if helpful to convey the information or units of measure.