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The Java™ Tutorials
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Annotations
Annotations Basics
Declaring an Annotation Type
Predefined Annotation Types
Type Annotations and Pluggable Type Systems
Repeating Annotations
Questions and Exercises
Trail: Learning the Java Language
Lesson: Annotations
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# Questions and Exercises: Annotations

## Questions

1. What is wrong with the following interface?

       public interface House {
           @Deprecated
           void open();
           void openFrontDoor();
           void openBackDoor();
       }

2. Consider this implementation of the `House` interface, shown in Question 1.

       public class MyHouse implements House {
           public void open() {}
           public void openFrontDoor() {}
           public void openBackDoor() {}
       }

   If you compile this program, the compiler produces a warning because `open` was deprecated (in the interface). What can you do to get rid of that warning?

3. Will the following code compile without error? Why or why not?

       public @interface Meal { ... }

       @Meal("breakfast", mainDish="cereal")
       @Meal("lunch", mainDish="pizza")
       @Meal("dinner", mainDish="salad")
       public void evaluateDiet() { ... }

## Exercises

1. Define an annotation type for an enhancement request with elements `id`, `synopsis`, `engineer`, and `date`. Specify the default value as `unassigned` for engineer and `unknown` for date.

Check your answers.

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