It is the most popular design pattern. It comes under the behavioral pattern category.

Publishers + Subscribers = Observer Pattern

  1. Publisher: Who publishes something.
  2. Subscriber: Who subscribes to a publisher.

Let us understand by taking a real-life example of YouTube. Today everyone uses YouTube. So, I think it will be the best example to explain.


Hey, I’m back with a new design pattern.

It is used when you:

  1. Need to add additional functionality/responsibility to an object dynamically.
  2. Need to remove functionality/responsibility from an object.
  3. Want to avoid too many sub-classes for adding additional functionality/responsibility.

Let’s take an example of everyone’s favorite Pizza shop. Suppose we want to create a pizza…

Do you know how easy it is?

This design pattern is a part of the creational design pattern.

Let us discuss first why to use it?

Problem: You might have face the following issues while passing too many parameters in a method or constructor.

  1. There could be a change in…

In this article, I’m going to explain how to print numbers without using any number in your code using java.

Hack 1: Use ASCII values

Hack 2: Use String length

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In the Software industry quality assurance is a very important term we use. And it must be important as development is. But in some of the middle-level industries, we ignore this thing. We just think about development only. But quality assurance is important as development is.

Quality assurance can strengthen…

Hunny Chawla

Application Developer

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