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Answers to Questions and Exercises: Nested Classes

### Questions

> Question 1: The program `Problem.java` doesn't compile. What do you need to do to make it compile? Why?
> Answer 1: Delete `static` in front of the declaration of the `Inner` class. An static inner class does not have access to the instance fields of the outer class. See `ProblemSolved.java`.

> Question 2: Use the Java API documentation for the `Box` class (in the `javax.swing` package) to help you answer the following questions.

> > a. What static nested class does `Box` define?
> > Answer 2a: `Box.Filler
> > ` b. What inner class does `Box` define?
> > Answer 2b: `Box.AccessibleBox
> > ` c. What is the superclass of `Box`’s inner class?
> > Answer 2c:`[java.awt.]Container.AccessibleAWTContainer
> > ` d. Which of `Box`’s nested classes can you use from any class?
> > Answer 2d: `Box.Filler
> > ` e. How do you create an instance of `Box`’s `Filler` class?
> > Answer 2e:`new Box.Filler(minDimension, prefDimension, maxDimension)`

### Exercises

> Exercise 1: Get the file `Class1.java`.

> > a. Compile and run `Class1`. What is the output?
> > Answer:
> > `InnerClass1: getString invoked.
> > InnerClass1: getAnotherString invoked.`

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