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Java OOP – Inheritance (Part II)

In the last article we discussed about 6 cases from Inheritance (Part I), one of the main concepts in OOP. Make sure that you have knowledge on those cases before reading of the today article. Let’s go to the rest of the Interface lesson. Case VII When a sub class object is initiated in the […]

August 10, 2020

Design Patterns

Behavioral – Iterator Design Pattern

Iterator pattern is a behavioral pattern that used to provide a standard way to go across a group of objects. This is relatively simple and frequently used design pattern. According to GoF, Iterator pattern provides a way to access the elements of an aggregate object without exposing its underlying representation. Let’s understand iterator pattern with […]

August 10, 2020

JAVA OOP

Java OOP -Inheritance (Part I)

According to the Oracle, In the Java language, classes can be derived from other classes, thereby inheriting fields and methods from those classes is called Inheritance. A class that is derived from another class is called a sub class (also a derived class, extended class, or child class). The class from which the subclass is derived is called a super class (also a base class or a parent class). […]

August 9, 2020

Design Patterns

Behavioral – Interpreter Design Pattern

Interpreter pattern is a behavioral design pattern that used to define a grammatical representation for a language and provides an interpreter to deal with the grammar. This is used in SQL passing, symbol processing engine etc. Let’s see an example of interpreter design pattern. “Expression” is the interface to check the interpreter. For that there […]

August 8, 2020

JAVA OOP

Java OOP – Static variables and methods

All the static members are created in the template and we can access them without an object. Non-static variables and methods cannot access without an object. Static members are common for all the instances(objects) of the class but non-static members are separate for each instance of class. Today we are going to talk about static […]

August 8, 2020

Design Patterns

Behavioral – Command Design Pattern

There are 10 behavioral design patterns and command pattern is one of them. This is used to implement loose coupling in a request-response model. Given below is the process of command pattern. —-request—-> Invoker —-request—> Command object —-request—>Receiver The command object is encapsulated. The client program creates the receiver object after passing the request to […]

August 7, 2020

JAVA OOP

Java OOP – Constructor

A constructor is a block of code that initializes newly created object. This is not a method because this doesn’t have a return type. But before you learn about constructors, make sure that you know about the methods. You can visit the articles of the Java Basics (Java Methods) tutorial. When we create a constructor, […]

August 7, 2020

Design Patterns

Behavioral – Observer Design Pattern

Observer pattern is classified among Behavioral patterns. This pattern is using if there is a many-to-many relationship between the objects inside a program. That means when a behavior of one object is affecting to many other objects inside the program. Let’s check it out from an example in java. This is on a salary […]

August 6, 2020

JAVA OOP

Java OOP – Objects/Classes/Attributes

In the last article we discussed about an Introduction on Java OOP. Today’s article is on the topics Objects, Classes and Attributes. Objects In the real world you can see many objects such as animals, humans, and vehicles etc. All these have a state and a behavior. Software Objects also have a state and a […]

August 6, 2020

Design Patterns

Structural – Flyweight Design Pattern

Flyweight Pattern is a Structural Design Pattern that used when we need to create a large number of similar objects. That means this pattern provides ways to decrease object count thus improving application required object structure. Once flyweight objects have been constructed, they cannot be modified. Let’s see a java program to demonstrate working of […]

August 5, 2020

JAVA OOP

Java OOP – Introduction

Before the using of concept Object Oriented Programming (OOP), people used the structural programming methodology. In structural programming, coding effort is very high and also complex. So to reduce the coding effort and complexity, James Gosling created the concept of Object Oriented Programming. Object oriented system design is another aspect to come up with the […]

August 4, 2020

Design Patterns

Structural – Proxy Design Pattern

Proxy design pattern is a Structural design pattern that provides a class which will limit the access to another class. This is something that authorized to handle the requests on behalf of the original object. Proxy pattern is applicable in four common situations. Virtual proxy – The real object is only created when a client […]

August 4, 2020