REVATURE COMPREHENSIVE TEST PAPER
2026 QUESTIONS AND CORRECT ANSWERS
GRADED A+
●● Class.
Answer: Blueprint/prototype from which objects are created
●● Inheritance.
Answer: subclasses can inherit states/behaviors of superclasses
●● interface.
Answer: contract between class and outside world; when a class
implements an interface, it promises to provide the behavior published
by that interface
●● package.
Answer: a namespace for organizing classes & interfaces in a logical
manner; makes large software projects easier to manage
●● Encapsulation.
Answer: Hiding the internal state of an object and requiring all
interaction to be performed through an object's methods (accessors and
mutators).
,Example: In a Bicycle class, method changeGear() could be
implemented so as to only accept values between 1 and 6
●● Benefits of Objects.
Answer: Modularity
Information-Hiding
Code re-use
Pluggability and debugging ease
●● Modularity.
Answer: source code for an object can be written/maintained
independently of source code for other objects. objects can be easily
passed around the system once they've been created.
●● Information-Hiding.
Answer: By interacting only with object's methods, details of internal
implementation stay secret from outside world.
●● Code re-use.
Answer: Complex objects only need to be coded once; you can use
classes that have already been created by others.
,●● Pluggability/Debugging Ease.
Answer: If an object is causing problems, you can easily remove it and
put something else in its place.
Example: replace a bolt that is broken, not the whole machine.
●● How to use the changeGear() method on a Bicycle bike1?.
Answer: bike1.changeGear();
●● How many superclasses can a subclass have?.
Answer: ONLY ONE
●● How many subclasses can inherit from the same superclass?.
Answer: Infinitely many
●● What is the main benefit of using inheritance?.
Answer: The subclass contains all of the methods/fields of the
superclass, but the subclass' code focuses on the unique aspects, making
code simpler and easier to read.
●● Why must the superclass' code be carefully documented?.
Answer: Because that code is not physically in the subclass.
, ●● Interface.
Answer: the methods that a class is required to contain; empty methods
that are related
●● Should the methods in an interface be public or private?.
Answer: MUST be public
●● Packages.
Answer: organizes a set of related classes/interfaces; like a folder on
your computer
●● class library.
Answer: a set of packages
●● API.
Answer: Application Programming Language: Java's library of classes
that you can use in your own applications.
●● What do the Java API's packages represent? Give examples..
Answer: tasks for general purpose programming: String, File, Socket,
some for developing GUIs.
●● What is a benefit of using packages?.
2026 QUESTIONS AND CORRECT ANSWERS
GRADED A+
●● Class.
Answer: Blueprint/prototype from which objects are created
●● Inheritance.
Answer: subclasses can inherit states/behaviors of superclasses
●● interface.
Answer: contract between class and outside world; when a class
implements an interface, it promises to provide the behavior published
by that interface
●● package.
Answer: a namespace for organizing classes & interfaces in a logical
manner; makes large software projects easier to manage
●● Encapsulation.
Answer: Hiding the internal state of an object and requiring all
interaction to be performed through an object's methods (accessors and
mutators).
,Example: In a Bicycle class, method changeGear() could be
implemented so as to only accept values between 1 and 6
●● Benefits of Objects.
Answer: Modularity
Information-Hiding
Code re-use
Pluggability and debugging ease
●● Modularity.
Answer: source code for an object can be written/maintained
independently of source code for other objects. objects can be easily
passed around the system once they've been created.
●● Information-Hiding.
Answer: By interacting only with object's methods, details of internal
implementation stay secret from outside world.
●● Code re-use.
Answer: Complex objects only need to be coded once; you can use
classes that have already been created by others.
,●● Pluggability/Debugging Ease.
Answer: If an object is causing problems, you can easily remove it and
put something else in its place.
Example: replace a bolt that is broken, not the whole machine.
●● How to use the changeGear() method on a Bicycle bike1?.
Answer: bike1.changeGear();
●● How many superclasses can a subclass have?.
Answer: ONLY ONE
●● How many subclasses can inherit from the same superclass?.
Answer: Infinitely many
●● What is the main benefit of using inheritance?.
Answer: The subclass contains all of the methods/fields of the
superclass, but the subclass' code focuses on the unique aspects, making
code simpler and easier to read.
●● Why must the superclass' code be carefully documented?.
Answer: Because that code is not physically in the subclass.
, ●● Interface.
Answer: the methods that a class is required to contain; empty methods
that are related
●● Should the methods in an interface be public or private?.
Answer: MUST be public
●● Packages.
Answer: organizes a set of related classes/interfaces; like a folder on
your computer
●● class library.
Answer: a set of packages
●● API.
Answer: Application Programming Language: Java's library of classes
that you can use in your own applications.
●● What do the Java API's packages represent? Give examples..
Answer: tasks for general purpose programming: String, File, Socket,
some for developing GUIs.
●● What is a benefit of using packages?.
