Ways to implement Proxy Pattern in Node.js

Sometimes we may want to access indirectly to an object, via a substitute. That substitute is called Proxy. The Proxy Pattern helps us deal with a proxy object and talk to the actual object. In this tutorial, we’re gonna look at 2 ways to implement Proxy Pattern in Node.js:

  • Using custom Proxy Class
  • Using Proxy API

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How to implement Dependency Injection in Node.js with Example

Dependency Injection is one form of Inversion of Control technique that supports the Dependency Inversion principle (the last one of SOLID Principles – decoupling software modules). In this tutorial, we’re gonna look at way to implement Dependency Injection pattern in Node.js.

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How to implement Builder Pattern in Node.js

When we want to create complicated object which has multiple parts, we can use Builder Pattern that separates the building of these parts. This creational process does not care about how these parts are assembled.

In this tutorial, we’re gonna look at 2 ways to implement Builder Pattern in Node.js:

  • using Builder function
  • using Builder class

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How to implement simple Factory Pattern in Node.js

Instead of using class constructors or new keyword to create an object of a class, we can abstract this process. So, we can determine the type of object at run-time, by the time of generating that class object. The implementation seems like Factory Method, but simpler than Factory Method. This simple Factory is not treated as a standard GoF design pattern, but the approach is common to any place where we want to separate the code that varies a lot from the code that does not vary.

In this tutorial, grokonez shows you how to do it in NodeJs.

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How to implement Singleton in Node.js

Singleton is object that can have only a single, unique instance, with a single point of access. Node.js module system provides simple way to implement Singleton using module.exports. Module will be cached when it is accessed using require() statement. So our module is merely a cached instance although it behaves like a Singleton.

In this tutorial, we’re gonna look at ways to implement this kind of Singleton in Node.js:

  • Singleton Object
  • Singleton Class

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Java Prototype Pattern tutorial with example

In many cases, creating a new instance is a costly operation. Fortunately, we can copy or clone an instance of an existing one instead of creating from scratch. This approach can be done by using Prototype Pattern, one of Creational Patterns.

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Kotlin Singleton with Object Declaration

In object oriented programming, there is a common situation when you want a class to have only one instance. In Java, we usually implement using the Singleton Design Pattern: define a class with a private constructor and a static field holding the only existing instance of that class. This tutorial shows you a way to implement Singleton with Kotlin Object Declaration.

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Chain of Responsibility Pattern in Java

Chain of Responsibility Pattern is a Behavioral Pattern in which, a Request is sent through a chain of handling Objects without knowing which Object will handle it. With Chain of Responsibility Pattern, we can avoid coupling the Sender of a request to received Objects and create a processing sequence automatically based on type of request.

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