Test your knowledge

1. When Java executes the code within a constructor:
   1. We cannot access any members defined in the class.
   2. There is already a live instance of the class. We can access methods defined in the class but we cannot access its fields.
   3. There is already a live instance of the class and we can access its members.
2. Constructors are extremely useful to:
   1. Execute setup code and properly initialize a new instance.
   2. Execute cleanup code before the instance is destroyed.
   3. Declare methods that will be accessible to all the instances of the class.
3. Java 9 uses one of the following mechanisms to automatically deallocate the memory used by instances that aren't referenced anymore:
   1. Instance map reduce.
   2. Garbage compression.
   3. Garbage collection.
4. Java 9 allows us to define:
   1. A main constructor and two optional secondary constructors.
   2. Many constructors with different arguments.
   3. Only one constructor per class.
5. Any new class we create that doesn't specify a superclass will be a subclass of:
   1. java.lang.Base
   2. java.lang.Object
   3. java.object.BaseClass
6. Which of the following lines create an instance of the Rectangle class and assign its reference to the rectangle variable:
   1. var rectangle = new Rectangle(50, 20);
   2. auto rectangle = new Rectangle(50, 20);
   3. Rectangle rectangle = new Rectangle(50, 20);
7. Which of the following lines access the width field for the rectangle instance:
   1. rectangle.field
   2. rectangle..field
   3. rectangle->field