j2ee design pattern interview questions – Software Design Patterns Tutorial PDF for Beginners and Experienced Developers

j2ee design pattern interview questions: A very popular concept among software developers is Design Patterns. BTech Geeks Software Design Patterns Tutorial for Beginners aids in understanding what is a design pattern, types of java software design patterns, benefits of using Design Patterns, and a list of covered tutorials available related to Software Design Patterns, etc.

List of Concepts covered in Software Design Patterns Tutorial

  • Designing a Board Game (Mastermind) in C++ using MVC, State, and Observer Design Patterns
  • Designing Event Handling Framework using Command Design Pattern
  • Need of Factory Method Design Pattern in Frameworks Explained
  • Designing a Multiton: Singleton that returns 5 objects in cycle
  • Design Sorting algorithm using Strategy Design Pattern
  • Learn State Design Pattern by Designing a Simple Music System
  • Task Grouping Using Composite Design Pattern
  • Designing a Configurable Logging framework using Observer Design Pattern
  • Binary Tree Traversal with Strategy design pattern and open-closed principle

What is Software Design Pattern?

Software design pattern represents a few best practices used by experienced Object-oriented software developers. Systematically, design patterns address the general design and provide solutions for the problems occurred in software design.

Basically, Design Patterns are programming language autonomous tactics for solving normal problems means they depict an idea, not a specific implementation. In short, a design pattern is a well-explained solution to the general software problem.

Also Check: STL Tutorials and Interview Questions

Categorization of Software Design Patterns

Generally, the categorization of software design patterns is done in two parts. They are as follows:

  • Core Java (or JSE) Design Patterns.
  • JEE Design Patterns.

Core Java Design Patterns

The list of core java design pattern types is given here clearly. Mainly in Java, there are three types of Design Patterns and they are divided into sub-parts as listed below:

1. Creational Design Pattern

  • Factory Pattern
  • Abstract Factory Pattern
  • Singleton Pattern
  • Prototype Pattern
  • Builder Pattern.

2. Structural Design Pattern

  • Adapter Pattern
  • Bridge Pattern
  • Composite Pattern
  • Decorator Pattern
  • Facade Pattern
  • Flyweight Pattern
  • Proxy Pattern

3. Behavioral Design Pattern

  • Chain Of Responsibility Pattern
  • Command Pattern
  • Interpreter Pattern
  • Iterator Pattern
  • Mediator Pattern
  • Memento Pattern
  • Observer Pattern
  • State Pattern
  • Strategy Pattern
  • Template Pattern
  • Visitor Pattern

JEE or J2EE Design Patterns

The second categorized design pattern is J2EE or JEE Design Pattern which are made to grow the Enterprise Web-based Applications. Also, they are divided into three types of design patterns. In the below list, we have provided the types of JEE Design patterns along with their sub-parts.

1. Presentation Layer Design Pattern

  • Intercepting Filter Pattern
  • Front Controller Pattern
  • View Helper Pattern
  • Composite View Pattern

2. Business Layer Design Pattern

  • Business Delegate Pattern
  • Service Locator Pattern
  • Session Facade Pattern
  • Transfer Object Pattern

3. Integration Layer Design Pattern

  • Data Access Object Pattern
  • Web Service Broker Pattern

Advantages of Design Pattern in Software

Some of the benefits of a software design pattern are furnished here below:

  • In many projects, design patterns are reusable.
  • They capture the software engineering experiences.
  • It helps in providing the solutions to define the system architecture.
  • Also, it gives transparency to the application design.
  • It doesn’t ensure an exact solution to a problem but provides transparency to the system architecture and the feasibility of establishing a reliable system.
  • Design Patterns are well documented and testified solutions as they have been created upon the knowledge and expert software developers’ experiences.

Usage of Design Pattern

Mainly, Design Patterns are used for two usages in software development. They are as fashion:

1. Common platform for developers:

Design patterns give standard terminology and are particular to unique scenarios. For instance, a singleton design pattern means the use of a single object so all developers aware of a single design pattern will practice a single object and they can spread each other that the program is following a singleton pattern.

2. Best Practices:

Design patterns have been developed over a long period of time and they implement the best solutions to real problems encountered at the time of software development. Learning these patterns aids non-experienced developers to understand software design effortlessly & quickly.

Software Design Patterns Interview Questions List

Let’s take a glimpse at the most commonly questioned software design pattern interview questions. These topmost interview questions on Design patterns will aid freshers and beginners in coding interviews also in competitive exams.

  1. What is a design pattern? Have you used any design patterns in your code?
  2. What Is Gang of Four (GOF)?
  3. What are the Creational Patterns?
  4. What is the main benefit of using factory pattern? Where do you use it?
  5. What is the MVC design pattern? Give one example of an MVC design pattern?
  6. Describe in how many ways can you create a singleton pattern?
  7. What is Chain of Responsibility pattern?
  8. Name some of the design patterns which are used in JDK library.
  9. What are the difference between a static class and a singleton class?
  10. Discuss the strategy to describe a design pattern.