Spring Boot App Behind the Scenes

Today, I came across one of the rarest of the rarest scenarios of a programmer's life. An algorithm problem in a production app... The problem was to find the index of the first unread message from a list of messages provided by the backend to the Android frontend app written in Kotlin. The unread messages are stored at the end of the list. As the list of messages in a single session is usually very short, the obvious solution is to use a linear search and stop at the index of the first unread message. However, I took it as a challenge and coded a simple binary search algorithm that gets the job done in O(log n) time. (P.S. I will still be using a simple Linear Search. Oftentimes, the better choice is to let your code be more readable and more approachable, rather than saving 0.5 ms in a single session) #leetcode #programming #softwareengineering #android #androiddevelopment #kotlin #java #androidstudio

⚙️ Phase 2: What’s Inside a Spring Boot App? When you add spring-boot-starter-web, something interesting happens… You’re not just getting libraries. You’re getting: ✔️ A web server ✔️ Servlet container ✔️ Auto-configuration ✔️ Production-ready defaults By default, Spring Boot includes an embedded server. That means: 👉 No need to install anything manually 👉 Your app becomes self-contained Even better: You can switch servers easily by changing dependencies. Your app is no longer tied to a single runtime environment. 💡 This abstraction is what makes Spring Boot flexible and production-friendly. Next post: What actually happens when you run your Spring Boot app? #SpringBoot #Java #BackendDevelopment #SoftwareEngineering  #SystemDesign #WebDevelopment #Programming #Developers #SpringFramework #Microservices #JavaBackend #TechDeepDive  #APIDevelopment

🚀 Lambda Functions in Kotlin – Make Your Code Cleaner & Smarter If you’re an Android developer, mastering lambda functions can seriously level up your code quality 💡 👉 What is a Lambda Function? A lambda is basically a short, anonymous function that you can pass around as a value. ✨ Basic Syntax: val sum = { a: Int, b: Int -> a + b } println(sum(5, 3)) // Output: 8 🔥 Why use Lambda? ✔ Less boilerplate code ✔ Improves readability ✔ Perfect for callbacks & listeners ✔ Works great with higher-order functions 📱 Android Example: button.setOnClickListener { Toast.makeText(context, "Clicked!", Toast.LENGTH_SHORT).show() } No need for long anonymous classes 🙌 💡 Pro Tip: Use lambdas with functions like map, filter, forEach to write more expressive and concise code. ⸻ 💬 Are you using lambda functions in your projects? Or still stuck with old-style code? Let’s discuss! #AndroidDevelopment #Kotlin #Programming #CleanCode #Developers #MobileDevelopment

I used to think Android apps run on JVM… until I learned this. Turns out, that’s not really how it works. And most developers never realize this. --- Android doesn’t use the traditional JVM. It uses **ART (Android Runtime)** instead. Which means: ✔ Kotlin/Java code → compiled into DEX ✔ Runs on ART, not JVM ✔ Uses a mix of AOT + JIT compilation --- Once I understood this, everything clicked: • Why app startup behaves differently • Why memory optimization feels different from Java apps • Why some performance tricks don’t work the same --- I think a lot of us come from a Java background… So we naturally assume Android works the same way. But that’s not entirely true. --- 💬 What surprised you the most when you first learned this? #AndroidDevelopment #AndroidDev #Kotlin #MobileDevelopment #AppDevelopment #ARTvsJVM

👉 “Most developers can run a Spring Boot app. Senior developers understand what happens before it starts… and after it fails.” 💡 If you can explain: Bean creation lifecycle Auto-configuration ApplicationContext initialization You’re already ahead of 90% 👀 #SeniorDeveloper #JavaDeveloper #SpringFramework #CleanCode #Architecture #Backend #TechSkills #Programming #DevCommunity #SoftwareDesign

Over the past few months, I’ve been diving deeper into modern Android development. 👨💻 From XML → Jetpack Compose From MVP → Clean Architecture From Java → Kotlin The ecosystem is evolving fast, and honestly… it’s exciting. What I’ve learned so far: ✔ Good architecture saves you later ✔ UI should be declarative, not complicated ✔ Kotlin makes everything cleaner (when used right) Still learning every day. What are you currently exploring in Android? 🚀 #Android #Kotlin #Compose #SoftwareEngineering #MobileDev

𝐒𝐄𝐀𝐒𝐎𝐍 1 · 𝐄𝐏𝐈𝐒𝐎𝐃𝐄 5 𝐓𝐡𝐞 𝐒𝐃𝐊 𝐀𝐰𝐚𝐤𝐞𝐧𝐬 — 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐞𝐫𝐬 𝐄𝐧𝐭𝐞𝐫 𝐭𝐡𝐞 𝐀𝐫𝐞𝐧𝐚 It was a deliberate bet: get developers building before the phone even exists. If the apps are ready on launch day, users will follow. It worked beyond anyone's expectations. The Android SDK gave developers something they'd never had before: a complete, free, open platform with a clear architecture, a familiar language (Java), and zero permission required to publish. No carrier approval. No $99 developer fee. No 14-day review queue. Within 14 months, the Android Market had 50,000 apps. Within two years, 100,000+ developers had registered. What this episode breaks down: • The 5-layer Android architecture stack and what each layer does for developers • Why choosing Java was a stroke of genius: millions of devs already knew it • Java vs Kotlin vs C++, the full language breakdown for Android development • The SDK release timeline: from beta to 50,000 apps in under 2 years • How Android's "publish instantly" model compared to Apple's 14-day review process The phone was the hardware. The SDK was the invitation. And developers RSVPed in the hundreds of thousands. #AndroidSDK #AndroidDev #Java #Kotlin #MobileDevelopment #OpenSource #TechHistory #AndroidChronicles #SoftwareDevelopment #Programming

🚀 I just built a fully functional Quiz App in Android Studio using Java! After learning Android development, I created this Quiz App that tests users on Networking and Software Development concepts. 📱 Key Features: - User Registration with Name & Registration Number - Specialization Selection (Network Quiz / Software Quiz) - 10 Questions per category with multiple-choice answers - Countdown Timer (10 minutes per quiz) - Real-time score tracking - Detailed Results Page (Score %, Correct/Wrong Answers, Time Taken) - Satisfaction Rating with SeekBar - Thank You screen 🛠 Tech Stack: - Language: Java - Framework: Android SDK - Components: RadioButtons, SeekBar, CountDownTimer, Intents 📂 GitHub Repository: https://lnkd.in/eXbQGUyr This project helped me understand Android lifecycle, event handling, and building real-world applications. #AndroidDev #Java #QuizApp #MobileAppDevelopment #AndroidStudio #CodingProjects #SoftwareEngineering #LearningByBuilding

🚀 Kotlin Extension Functions — Clean Code Made Easy In day-to-day Android development, writing clean and maintainable code is essential. One powerful feature in Kotlin that helps achieve this is Extension Functions. 👉 What are Extension Functions? Extension functions allow you to add new functionality to an existing class without modifying its original code. fun String.addExclamation(): String { return this + "!" } Usage: val text = "Hello".addExclamation() // Hello! 💡 Why use Extension Functions? ✅ Improves Readability Call functions directly on objects, making code more natural and expressive. ✅ Reduces Boilerplate Code Avoid creating unnecessary utility or helper classes. ✅ Enhances Existing Classes Add your own behavior to built-in classes like "String", "Int", or Android views. ✅ Better Code Organization Keep related logic in one place, making your project easier to manage. 🔥 Real-world Android Example: fun View.show() { visibility = View.VISIBLE } fun View.hide() { visibility = View.GONE } Usage: button.show() textView.hide() ✨ Extension functions are small, but they make a big impact on code quality and developer productivity. 💬 Do you use extension functions in your projects? What’s your favorite use case? #Kotlin #AndroidDevelopment #CleanCode #JetpackCompose #SoftwareEngineering

🚀 Project 18: Android News App 📰 (With Demo) Just built a simple and clean News App using Java in Android Studio. 📽️ In the video below, you can see: Grid layout of newspapers Smooth UI interaction One-tap opening of news websites 🔑 Key Features: ✔️ GridView-based UI with logos ✔️ One-click access to top Bangladeshi newspapers ✔️ Live date display ✔️ Fast & lightweight 🛠️ Tech Stack: Java Android Studio GridView + Custom Adapter Intent (for opening URLs) 📚 What I Learned: Handling GridView item clicks Using implicit intents Structuring UI components Managing resources efficiently 💡 Next Plan: Add search 🔍 Favorite list ⭐ Offline reading 📶 Notification system 🔔 🎯 Still learning and building step by step. 🔗 GitHub: https://lnkd.in/gMcfM7zW #AndroidDevelopment #Java #MobileApp #100DaysOfCode #Learning #AppDevelopment