Creational Design Patterns
- Design Patterns - Factory Pattern
- Abstract Factory Pattern
- Design Patterns - Singleton Pattern
- Design Patterns - Builder Pattern
- Design Patterns - Prototype Pattern
Structural Design Patterns
- Design Patterns - Adapter Pattern
- Design Patterns - Bridge Pattern
- Design Patterns - Filter Pattern
- Design Patterns - Composite Pattern
- Design Patterns - Decorator Pattern
- Design Patterns - Facade Pattern
- Design Patterns - Flyweight Pattern
- Design Patterns - Proxy Pattern
- Chain of Responsibility Pattern
Behavioral Design Patterns
- Design Patterns - Command Pattern
- Design Patterns - Interpreter Pattern
- Design Patterns - Iterator Pattern
- Design Patterns - Mediator Pattern
- Design Patterns - Memento Pattern
- Design Patterns - Observer Pattern
- Design Patterns - State Pattern
- Design Patterns - Strategy Pattern
- Design Patterns - Template Pattern
- Design Patterns - Visitor Pattern
J2EE Design Patterns
- Design Patterns - Null Object Pattern
- Design Patterns - MVC Pattern
- Business Delegate Pattern
- Composite Entity Pattern
- Data Access Object Pattern
- Front Controller Pattern
- Intercepting Filter Pattern
- Service Locator Pattern
- Transfer Object Pattern
Design Patterns Useful Resources
Design Patterns Online Quiz
Following quiz provides Multiple Choice Questions (MCQs) related to Design Patterns Framework. You will have to read all the given answers and click over the correct answer. If you are not sure about the answer then you can check the answer using Show Answer button. You can use Next Quiz button to check new set of questions in the quiz.
Q 1 - Which of the following is correct about Singleton design pattern.
A - This type of design pattern comes under creational pattern.
Answer : D
Explanation
Singleton pattern is one of the simplest design patterns in Java. This type of design pattern comes under creational pattern as this pattern provides one of the best ways to create an object.This pattern involves a single class which is responsible to create an object while making sure that only single object gets created. This class provides a way to access its only object which can be accessed directly without need to instantiate the object of the class.
Answer : B
Explanation
true. Integer.valueOf() returns a Integer instance representing the specified int value.
Q 3 - Which of the following pattern is used when we need to decouple an abstraction from its implementation so that the two can vary independently?
Answer : A
Explanation
Bridge pattern is used when we need to decouple an abstraction from its implementation so that the two can vary independently.
Q 4 - Which of the following describes the Interpreter pattern correctly?
A - In this pattern a class represents functionality of another class.
B - This pattern creates a chain of receiver objects for a request.
C - This pattern provides a way to evaluate language grammar or expression.
D - In this pattern a request is wrapped under an object as command and passed to invoker object.
Answer : C
Explanation
Interpreter pattern provides a way to evaluate language grammar or expression. This type of pattern comes under behavioral pattern. This pattern involves implementing an expression interface which tells to interpret a particular context.
Q 5 - Which of the following describes the Memento pattern correctly?
B - This pattern is used to reduce communication complexity between multiple objects or classes.
C - This pattern is used to restore state of an object to a previous state.
Answer : C
Explanation
This pattern is used to restore state of an object to a previous state.
Q 6 - Which of the following describes the Visitor pattern correctly?
B - This pattern is used to separate application's concerns.
C - This pattern is used to decouple presentation tier and business tier.
Answer : A
Explanation
In Visitor pattern, a visitor class is used which changes the executing algorithm of an element class.
Q 7 - Which of the following pattern is used to to decouple presentation tier and business tier?
Answer : C
Explanation
Business Delegate pattern is used to decouple presentation tier and business tier.
Q 8 - Which of the following pattern is used when we want to do some pre-processing / post-processing with request or response of the application?
Answer : C
Explanation
Intercepting Pattern is used when we want to do some pre-processing / post-processing with request or response of the application.
Q 9 - Which of the following describes the Creational pattern correctly?
C - This type of pattern are specifically concerned with communication between objects.
D - This type of pattern are specifically concerned with the presentation tier.
Answer : A
Explanation
Creational Design Patterns provide a way to create objects while hiding the creation logic, rather than instantiating objects directly using new opreator.
Q 10 - Which of the following is the correct list of entities of Business Delegate pattern?
A - Business Delegate, LookUp Service, Business Service
B - Client, Business Delegate, LookUp Service, Business Service
Answer : B
Explanation
Client, Business Delegate, LookUp Service, Business Service are the entities of Business Delegate Pattern.