Avoid Field Injection in Spring Boot

⚙️ 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

Spent 20 minutes wondering why my Spring Boot app was starting slow. Checked everything. Database connections. External APIs. Nothing obvious. Then I found this: @SpringBootApplication @ComponentScan(basePackages = "com") Scanning "com" means Spring scans every package starting with com. Including third party libraries. The fix: @SpringBootApplication @ComponentScan(basePackages = "com.myapp") Be specific. Only scan your packages. Startup time dropped from 45 seconds to 12 seconds. Small change. Big difference. #SpringBoot #Java #Performance #BackendDevelopment #Programming

My system was getting slower every single day… Apps lagging, memory overloaded, productivity dropping 😤 So instead of complaining, I decided to build a solution. I was constantly facing: • High memory usage • Cache buildup over time • Slower performance after long usage And then I thought — this isn’t just my problem. Many of us deal with this daily. So I built an NPM package: 🔗 https://lnkd.in/gGuwbm2F 🏠 https://lnkd.in/gs7p5QZC It’s a simple tool that helps you: ✔️ Clean system cache ✔️ Free up memory ✔️ Speed up your system quickly No complex setup. Just install and run. This is my small attempt to solve a real-world problem using code 💻 Now I’d love your help to make it better 🙌 Try it out, share your feedback, suggest improvements, or contribute to the project. If you find it useful, feel free to share it with others 🚀 Because sometimes the best products come from solving your own problems. #opensource #npm #javascript #nodejs #developers #webdev #buildinpublic #productivity #programming #codinglife #devtools #techinnovation #indiedev #softwaredevelopment #github

Your Spring Boot app works perfectly… Until it doesn’t in production. Same code. Different behavior. Why? 𝗣𝗿𝗼𝗳𝗶𝗹𝗲𝘀 This is one of the most underrated features in Spring Boot. When you build an application, you don’t run it in just one environment. You usually have:  • Development (dev)  • Testing (test)  • Production (prod) And here’s the problem: Each environment needs different configurations. Different databases Different APIs Different logging levels You can’t hardcode all of this. That’s where Spring Boot Profiles come in. What do profiles do? They let you 𝘀𝘄𝗶𝘁𝗰𝗵 𝗰𝗼𝗻𝗳𝗶𝗴𝘂𝗿𝗮𝘁𝗶𝗼𝗻𝘀 based on the environment — without changing your code. Spring boot lets you manage this using .𝗽𝗿𝗼𝗽𝗲𝗿𝘁𝗶𝗲𝘀 or .𝘆𝗺𝗹 files, where each profile has its own dedicated configurations And you just activate it like: spring.profiles.active=prod Done. Your entire app behaves differently. Why this is powerful: No more “it works on my machine” issues Clean separation of environments Safer deployments Easy testing without breaking production Profiles are a small feature… But they solve a big real-world problem. Next time you build a Spring Boot app, Don’t just run it — run it with the right profile. #CoreJava #JavaDeveloper #SpringFramework #SpringBoot #Profiles #BackEndDevelopment #SoftwareEngineering #Programing #Developers #WebDevelopment #Environments #Microservices #aswintech

Most Spring Boot developers ship to production without knowing if their app is truly healthy. 🩺 You test your endpoints. Your CI passes. You deploy. But the moment something silently breaks, a database connection drops, an external API becomes unreachable, disk space runs out , your application keeps running, no errors, no alerts, just quietly serving failures to your users. That's the problem Health Checks solve. And Spring Boot makes it almost too easy to get right. 🩺 What is a Health Check? A simple mechanism that answers one question on a schedule: "Is this service actually ready to serve traffic?" Not just "is the JVM running?" — but "are all the pieces this app depends on working?" ⚡ Spring Boot Actuator , built-in and ready Add one dependency and you instantly get a /actuator/health endpoint that checks your database, MongoDB, disk space and more, automatically. UP ➡️ all good, serve traffic. DOWN ➡️ something is wrong, alert immediately. No custom code needed to get started. 🔧 But the real power is in custom indicators The default tells you if the app is alive. Custom health indicators tell you if your app is useful. You can write checks for anything: an external payment API, a message queue, a critical cache, if that dependency is down, your health endpoint reflects it, and your infrastructure reacts automatically. 💡 Two checks every production app needs: Liveness ➡️Is the app alive? Should it be restarted? Readiness➡️ Is the app ready to receive traffic? These two signals are especially critical in Kubernetes, they drive automatic restarts and traffic routing without any manual intervention. Are you using custom health indicators in your Spring Boot apps? Or just relying on the defaults? 👇 #Java #SpringBoot #HealthCheck #BackendDevelopment #SoftwareArchitecture #LearningInPublic #Kubernetes #Programming

🚀 Most developers misuse `FirstOrDefault` and `SingleOrDefault`… and it can break your logic. I’ve seen this mistake so many times in .NET codebases. Both look similar. Both return one item (or null). But they behave VERY differently 👇 Here’s what I learned 👇 ✔ `FirstOrDefault` Returns the **first match** it finds Does NOT care if multiple records exist ✔ `SingleOrDefault` Expects **ONLY one match** Throws an exception if multiple records exist ✔ Performance matters `FirstOrDefault` stops early `SingleOrDefault` scans full data to ensure uniqueness ✔ Use case matters Use `FirstOrDefault` → when multiple results are OK Use `SingleOrDefault` → when data MUST be unique 👉 Choosing the wrong one can hide bugs… or crash your app. Are you using `SingleOrDefault` correctly, or just hoping your data is clean? 🤔 #dotnet #csharp #softwaredevelopment #backend #programming #webdevelopment

🚀 Spring Configuration — The Backbone of Every Spring Boot App When I first started learning Spring Boot, I thought configuration was just “setup stuff.” Turns out… it’s the brain behind everything 🧠 🔹 What is Spring Configuration? It’s how you tell Spring: ✔️ What objects (beans) to create ✔️ How they connect (Dependency Injection) ✔️ How your app should run 🔹 3 Ways to Configure in Spring Boot 1️⃣ Annotation-Based (Most Common) Use "@Component", "@Service", "@Autowired" 👉 Clean, simple, and widely used 2️⃣ Java-Based Configuration Use "@Configuration" + "@Bean" 👉 Gives you full control when needed 3️⃣ application.properties / application.yml 👉 Configure ports, DB, and custom values 🔹 The Magic Annotation ✨ "@SpringBootApplication" It combines: - "@Configuration" - "@EnableAutoConfiguration" - "@ComponentScan" 👉 That’s why Spring Boot feels so easy! 🔹 Realization 💡 Spring Configuration is not just setup… It’s what makes your app: ✔️ Scalable ✔️ Maintainable ✔️ Production-ready 💬 My Take: If you truly understand configuration, you stop “using Spring” …and start thinking like Spring. #SpringBoot #Java #BackendDevelopment #LearnInPublic #Developers #CodingJourney

🚀 Redux Tutorial with Vite 2026 | Basic to Pro Level (Real Project) If you're learning React or preparing for frontend interviews, understanding Redux is a must 💯 In this video, I’ve explained Redux with Vite from Basic to Pro Level in a simple and practical way 👇 👉 What you’ll learn: ✅ Counter App (Hands-on Example) ✅ User List Project ✅ Redux Store, Reducers & Actions ✅ useSelector & useDispatch Hooks ✅ Complete Setup with Vite + React This tutorial is beginner-friendly and also covers important concepts needed to build scalable React applications 🚀 🎯 Perfect for: • React Developers • Frontend Interview Preparation • Beginners learning state management 📌 Watch the full video here: https://lnkd.in/g63TaNt9 ⏱️ Chapters: 00:00 Intro 01:15 Redux + Interview Questions 10:00 Setup of React & Redux 💬 Let me know your thoughts in the comments! #ReactJS #Redux #Vite #FrontendDevelopment #WebDevelopment #JavaScript #Coding #Programming #InterviewPreparation

🚨 Ever wondered what actually happens when a Spring Boot app starts? Most developers just run the app and move on. But understanding this helped me debug startup issues faster. Here’s the simplified flow 👇 Spring Boot initializes the ApplicationContext Auto-configuration kicks in (based on classpath) Beans are created and wired Embedded server (Tomcat) starts Application is ready to serve requests 💥 Real issue I faced: A misconfigured bean was slowing startup by ~20 seconds. Root cause? Unnecessary component scanning + heavy initialization logic inside a bean. ✅ Fix: Reduced scan scope Moved heavy logic to lazy initialization 💡 Takeaway: Startup time matters more than you think in microservices. Have you ever debugged a slow Spring Boot startup? #Java #SpringBoot #BackendDevelopment #SoftwareEngineering  #Microservices #RESTAPI #SystemDesign  #DeveloperLife #100DaysOfCode