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An item contains a limited number of constants.

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Using enum to ensure something can only be a limited number of values.

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In this lesson, you're going to create an enum.

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An enum defines a collection of static final constants.

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Using Inam to ensure a variable can only be a limited number of values.

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The size of a shirt should be limited to three values, small, medium or large.

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But what if the caller writes something like Wambo?

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They surely can assizes of type string so it can be anything.

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Then you might think that's OK.

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We could just apply exception handling if the caller writes anything bad.

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Yeah, but why do any of that?

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From the start, we just use an item to insure this variable can only be a limited number of values.

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So inside the shirt class, we're going to create a public item called size that defines three static

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final constants, small, medium, large.

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This is how you create an item.

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All you have to do is make sure to always capitalize constants inside of an item now by default, every

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value inside of an enormous final.

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These values can never be changed.

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Basically, an item is just a collection of final values.

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OK, now the problem with the size is that it's a strength, which means it can be any type of value,

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we're going to make it an enum type so that it's limited to only three.

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And now the constructor needs to receive an item constant.

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And now you're going to have to regenerate the getters and setters.

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Now, back in Maine, an enum is implicitly static, that means we can access it directly from the class.

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And now I can only give the shirt one of three values, small, medium or large, I'm going to give

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it a size of small.

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And now I can print the object.

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And everything works beautifully.

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You limited the size field to three possible values.

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Use an enum to ensure something can only be a limited number of values.