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How to Group Data and Find Maximums by Group in Angular using RxJS Have you ever faced an interview question where you need to take a flat list of employee records and group them by department to find the highest earner? While it sounds straightforward, doing this reactively with RxJS can quickly lead to tricky bugs if operators are chained out of order. In this post, we will look at a common broken snippet, dissect why it fails, and implement two clean ways to solve it. The Problem Scenario Imagine you have the following flat dataset inside an Angular component: employees = [ { id : 0 , name : "Mani" , dept : "IT" , salary : 12000 }, { id : 1 , name : "Lava" , dept : "IT" , salary : 1200 }, { id : 2 , name : "Nila" , dept : "Medical" , salary : 12000 }, { id : 3 , name : "Test" , dept : "IT" , salary : 12000 }, { id : 4 , name : "JHi" , dept : "Medical" , salary : 12000 }, {...

  JavaScript Fundamentals Every Angular Developer Must Know for Interviews (2026) If you're preparing for an Angular interview, especially for a Senior Angular Developer role, strong JavaScript fundamentals are essential. Many interviewers spend a significant portion of the interview testing JavaScript concepts because Angular is built on top of JavaScript and TypeScript. In this article, we'll cover the most important JavaScript interview topics with practical examples. 1. var vs let vs const These are used to declare variables, but they behave differently. var name = "Manikandan"; let age = 35; const country = "India"; Feature var let const Scope Function Block Block Reassign Yes Yes No Hoisted Yes Yes Yes Example if (true) { var a = 10; let b = 20; } console.log(a); // 10 console.log(b); // Error 2. Hoisting JavaScript moves declarations to the top during execution. console.log(name); var name = "Mani"; Output: undefined Internally, JavaSc...

JavaScript remains the foundation of modern web and hybrid mobile application development. Whether you're preparing for a Technical Lead, Senior Developer, Angular, Ionic, React, or Full Stack interview, mastering these core JavaScript concepts is essential. This guide covers the most frequently asked JavaScript interview questions along with concise professional answers. 1. What is the difference between var, let, and const? Feature| var| let| const Scope| Function| Block| Block Reassignment| Yes| Yes| No Redeclaration| Yes| No| No Hoisting| Yes| Yes| Yes Best Practice: Prefer "const" by default and use "let" only when reassignment is required. --- 2. What is Hoisting? Hoisting is JavaScript's behavior of moving variable and function declarations to the top of their scope during compilation. console.log(a); var a = 10; Output: undefined --- 3. What is a Closure? A closure allows a function to access variables from its outer scope even after the outer functi...

  Capacitor vs Cordova: Which Native Bridge Should Power Your Ionic App in 2025? Introduction For years, Apache Cordova was the foundation of hybrid mobile app development in the Ionic ecosystem. It enabled developers to build iOS and Android applications using web technologies such as HTML, CSS, and JavaScript. However, the mobile development landscape has evolved significantly. Modern operating systems, native APIs, TypeScript adoption, and developer experience requirements have pushed the ecosystem toward a newer solution: Capacitor . Today, Capacitor is the default native runtime for Ionic applications, while Cordova is primarily used to maintain legacy projects. In this article, we'll compare Capacitor and Cordova and help you decide which solution is right for your next Ionic project. What is Capacitor? Capacitor is a modern cross-platform native runtime created and maintained by the Ionic team. It allows developers to build applications using web technologies while...

✅  Tight Coupling Two classes/components are tightly coupled when they depend on each other directly. If one changes, the other must also change. It reduces flexibility and reusability. 📌 Example (Bad Practice – Tight Coupling) class UserRepository { fun getUser() = "Android Developer" } class UserViewModel { private val repository = UserRepository() // Direct object creation → TIGHT COUPLING fun printUser() { println(repository.getUser()) } } 🔴 Problems: UserViewModel cannot work without UserRepository Hard to unit test (cannot inject mock repo) If repository changes, viewmodel breaks Not reusable ✅ Loose Coupling Two classes are loosely coupled when they depend on abstractions (interfaces) instead of concrete classes. You can replace dependency without modifying main logic → more flexible. 📌 Example (Good Practice – Loose Coupling with DI) interface UserRepository { fun getUser(): String } class UserRepository...

If you’ve started learning Java, you’ve probably heard people say things like: “That variable is stored on the stack,” or “The object lives in the heap.” And then there’s something called the String Pool — sounds confusing, right? Don’t worry 😄 — this post will make everything super simple to understand. 🧩 Let’s start with: What happens when you run a Java program? When your Java code runs, the JVM (Java Virtual Machine) divides memory into different sections . The two most important ones are: Stack Memory Heap Memory Let’s see what each one does 👇 🥞 1. Stack Memory — for short-term data Think of Stack Memory as a temporary notebook 📒 that the JVM uses to store small, short-lived data. ✳️ Used for: Primitive variables ( int , char , boolean , etc.) References to objects (not the objects themselves) Method calls and local variables Every time a method is called, the JVM creates a stack frame for it. When the method finishes, its frame is r...