Test your knowledge

1. A class that exposes mutable fields will:

   1. Generate immutable instances.

   2. Generate mutable instances.

   3. Generate mutable classes but immutable instances.

2. Which of the following keywords, used within a constructor, allows us to call other constructors with different arguments defined in our class:

   1. self

   2. constructor

   3. this

3. An object that cannot change its state after it has been initialized is known as:

   1. A mutable object.

   2. An immutable object.

   3. An interface object.

4. In Java 9, java.lang.String generates:

   1. An immutable object.

   2. A mutable object.

   3. An interface object.

5. If we call the toUpperCase method for a java.lang.String, the method will:

   1. Convert the existing String to uppercase characters and change its state.

   2. Return a new String with the contents of the original String converted to uppercase characters.

   3. Return a new String with the contents of the original String.