Peter Glózik’s Post

🚀 Spring Boot 4 is Changing the Game for Null Safety! As a Java developer, we've all been there - the dreaded NullPointerException 💥  that crashes production at 2 AM. Spring Boot 4 (releasing November 2025) brings a game-changing feature:  JSpecify Null Safety Annotations ✨ 🔍 Here's how it prevents NPEs at COMPILE TIME: // ❌ Old Way (Runtime Explosion) @Service public class UserService {   public String getUserName(User user) {     return user.getName(); // 💣 NPE waiting to happen!   } } // ✅ New Way with JSpecify (Spring Boot 4) import org.jspecify.annotations.Nullable; import org.jspecify.annotations.NonNull; @Service public class UserService {   public @NonNull String getUserName(@Nullable User user) {     if (user == null) {       return "Guest"; // Compiler forces you to handle null!     }     return user.getName();   } } 🎯 What makes this powerful? 1️⃣ Compile-time checks - Catch bugs before deployment 2️⃣ IDE support - IntelliJ/Eclipse shows warnings immediately 3️⃣ Kotlin interop - Seamless null safety with Kotlin projects 4️⃣ Clear contracts - Method signatures tell the truth about nullability 💡 Real Impact: - Reduced production bugs by catching NPEs during development - Better code documentation (nullability is explicit) - Safer API contracts between microservices Spring Boot 4 + JSpecify = Fewer debugging sessions! 😴 Are you ready to upgrade when Spring Boot 4 GA releases this November? #SpringBoot #Java #NullSafety #SoftwareEngineering #BackendDevelopment

Hi Java fellows 👋 and Spring enthusiasts 🌿, The releases of Spring Framework 7 (November 13th) and Spring Boot 4 (November 20th) are just around the corner, and here's what you should know: Spring Framework 7: ✅ Resilience features: RetryTemplate, @Retryable, @ConcurrencyLimit ✅ API Versioning ✅ Null Safety with JSpecify ✅ Programmatic Bean Registration ✅ HTTP Interface Client configuration .... Release note:🔗 https://lnkd.in/g7SfnbBk Spring Boot 4: ✅ HTTP Service Clients ✅ OpenTelemetry starter ✅ Improved Observability ✅ Native Image Improvements ... Release note: 🔗https://lnkd.in/gDcGR3KJ (Draft version) For a deeper dive into what's coming, check out the official "Road to GA Introduction" blog post here: https://lnkd.in/g3gXyEn6 Happy learning! 👨💻🎉 #SpringFramework #SpringBoot #Java #SpringFramework7 #SpringBoot4

🔥 Spring Boot 4: Real Null-Safety at Last! 🚀 For years, null in Java has been a guessing game. When you see a method like: User findUserByEmail(String email) Can it return null? Maybe. Maybe not. You guess, you hope, and sometimes… 💥 boom — a NullPointerException in production. With Spring Boot 4, that uncertainty is finally over. 👉 Thanks to @NullMarked, powered by JSpecify and NullAway, null-safety becomes explicit. Here’s what it means in practice: Add @NullMarked once at the package level Your IDE instantly shows you where nulls are risky The compiler helps you fix issues before they ever hit runtime No more gray areas. Every parameter, return type, and variable clearly tells you whether it can be null or not. Your code becomes more predictable, more readable, and above all — safer. 💡 Daily benefits: ✅ Fewer bugs and production surprises ✅ Clearer method contracts ✅ Self-documenting code ✅ Easier reviews and maintenance It’s a small change in syntax, but a huge leap for Java’s ecosystem. Finally, safety and clarity take the spotlight. Bonus: modern IDEs (IntelliJ, Eclipse, VS Code) already integrate perfectly with JSpecify and NullAway. You see warnings as you type — fix issues before they exist. In short, Spring Boot 4 doesn’t just add features — it upgrades the developer experience and makes your codebase trustworthy again. 💪 If you’re tired of endless Optionals, manual null checks, and unpredictable NPEs… #SpringBoot #Java #CleanCode #NullSafety #DeveloperExperience #SpringBoot4 #JSpecify #NullAway

🚀 Day 2 of 100: Java Developer Journey As I mentioned earlier, I already have experience with Java and have built projects before — but this 100-day journey is about diving deep and solidifying my conceptual understanding. Today, I explored what happens behind the scenes when we run a Java program, where the concepts of JDK, JRE, and JVM come into play. 🧰 JDK (Java Development Kit): It’s the full toolkit for Java developers. It includes tools like javac, java, debuggers, and libraries needed to develop and compile Java programs. ⚙️ JRE (Java Runtime Environment): This provides everything required to run a Java program. It contains the JVM and essential core libraries such as java.util, java.lang, and java.io. 🔥 JVM (Java Virtual Machine): This is the engine inside the JRE that actually executes your compiled bytecode (.class files). Its responsibilities include: ▪️ Loading and verifying bytecode ▪️ Managing memory (via Garbage Collection) ▪️ Providing platform independence 💡 Example: public class Hello {   public static void main(String[] args) {     System.out.println("Hello Java!");   } } ▪️ When we run javac Hello.java, the JDK compiler converts our code into bytecode (Hello.class). ▪️ When we run java Hello, the JRE loads the JVM, which executes that bytecode line by line. ▪️ The output will be: Hello Java! 🧠 Key takeaway: The bytecode (.class file) is platform-independent — it can run on any system (Windows, Linux, or macOS) that has a compatible JVM. #Java#SpringBoot#LearningJourney#Consistency#100DaysOfCode

🔥 Spring Framework 7 just made bean registration actually elegant. No more messy post processors. No more conditional chaos. The new BeanRegistrar gives you direct access to the bean registry and environment properties — clean, flexible, and perfect for dynamic setups (multi-tenant, feature flags, or conditional services). 🎥 Watch Dan Vega's excellent breakdown: 👉 https://lnkd.in/gbaM_yry Spring Framework 7 & Boot 4 drop this November — this update alone changes how we design Spring apps. 💬 Where could you use dynamic bean registration today? 🔁 Repost to help other Java devs discover this update 👥 Follow Pondurai Madheswaran for more Spring & Java deep dives #SpringBoot4 #SpringFramework7 #Java #Microservices #CleanCode #DanVega #SoftwareEngineering

📊 Java Evolution: A Quick Guide for Developers Understanding Java's journey is crucial for every developer. Here's what each major version brought to the table: Java 8 (2014) - The game changer • Lambdas & Streams revolutionized how we write code • Optional helped us handle nulls elegantly • Date/Time API finally got it right Java 11 (2018) - The LTS favorite • var keyword for local variables • HTTP Client API became standard • Java EE modules removed (leaner JDK) Java 17 (2021) - Modern LTS • Sealed classes for controlled inheritance • Pattern Matching for instanceof • Text Blocks for cleaner multi-line strings Java 21 (2023) - The latest LTS • Virtual Threads (Project Loom) - massive scalability • Pattern Matching for Switch • Record Patterns for cleaner data handling Java 25 (Preview Features) • Performance improvements across the board • Project Panama for native code integration • Valhalla bringing value types to the table 💡 Key Takeaway: If you're still on Java 8, you're missing out on tremendous productivity gains. Java 17 or 21 should be your target for new projects. What Java version is your team using? Share in the comments! 👇 #Java #SoftwareEngineering #Programming #TechCommunity #JavaDevelopment

🚀 Spring Boot 4: Real Null-Safety at Last! For years in Java we’ve played the guessing game around null. When you see a method like: User findUserByEmail(String email) Can it return null? Maybe. Maybe not. You hope it won’t… and sometimes — 💥 boom — a NullPointerException in production. With Spring Boot 4, that uncertainty is finally over. Thanks to the @NullMarked support (via JSpecify & NullAway) the nullability of your APIs becomes explicit. Here’s what it means in practice: Add @NullMarked at the package level → by default, types are non-null unless annotated otherwise. The IDE (IntelliJ, Eclipse, VS Code) immediately shows where nulls are risky. The compiler and build tools (via NullAway) help you fix issues before runtime. Every parameter, return type and field clearly tells you whether it can be null or cannot. Your code becomes more predictable, more readable, and above all — safer. 💡 Daily benefits: ✅ Fewer bugs and production surprises ✅ Clearer method and API contracts ✅ Self-documenting code for teammates and reviewers ✅ Easier code reviews and maintainability ✅ Better interoperability (especially with Kotlin, which understands nullability) But null-safety isn’t the only upgrade in Spring Boot 4.0. Among other improvements: Baseline requirement of Java 17+ — unlocking records, sealed classes, pattern-matching, better performance. Enhanced native image and ahead-of-time (AOT) compilation support, making microservices start faster and use fewer resources. Improved API versioning support, so evolving REST-APIs become easier to maintain side-by-side. In short: Spring Boot 4 doesn’t just add features — it upgrades the developer experience and makes your entire codebase more trustworthy. 💪 If you’re tired of endless Optionals, manual null checks, and unpredictable NPEs — it’s time to take the leap. #SpringBoot #Java #CleanCode #NullSafety #DeveloperExperience #JSpecify #NullAway

Many developers still stop at Java 8! Yes, most people deeply focus on Java 8 features — and that’s absolutely fine, because Java 8 was revolutionary (Streams, Lambdas, Functional Programming, Optional, etc.). However, what surprises me is that many developers don’t even explore the next versions of Java, such as Java 11, Java 17, or the upcoming Java 21/25 LTS versions, which bring significant performance, syntax, and productivity improvements. A quick reality check: Java 8 (2014) – Functional programming, Streams, Lambda expressions, Optional, Date/Time API. Java 11 (2018) – var keyword for local variables, new HTTP Client API, String utility methods, and removal of old APIs. Java 17 (2021, LTS) – Sealed classes, Pattern Matching for instanceof, Records, Switch Expressions, and better performance. Java 21 (2023, LTS) – Virtual Threads (massive boost for concurrency), Pattern Matching for Switch, Sequenced Collections, and Record Patterns. Java 25 (expected 2025, future LTS) – continues to refine performance, memory efficiency, and language simplicity. The takeaway? If you’re still coding only with Java 8 in mind, you’re missing out on features that make your code cleaner, faster, and more scalable. Let’s not just “know Java 8,” Let’s evolve with Java. #Java #JavaDeveloper #Java17 #Java21 #Programming #FullStack #SoftwareDevelopment #LearningEveryday

Ever spent hours debugging a Java app… only to find a tiny typo caused it? 😅 Mastering Java isn’t just coding—it’s solving real world problems. As a Java backend developer, I focus on small habits that make a huge difference: 1. Writing clean, modular code. 2. Building scalable apps with Spring Boot & Spring Security. 3. Catching bugs early with JUnit tests. 4. Optimizing database queries with MySQL. These practices don’t just prevent errors—they save time and reduce stress in the long run. What’s one habit that transformed your workflow? Drop it in the comments— 👇

Don't miss my new blog post in the Road to GA series to learn how the Spring team empowers Spring developers to make their Spring Boot 4 application null-safe, to reduce or remove the risk of NullPointerException and to solve "the billion dollar mistake"! https://lnkd.in/dZ-Tj4FP #spring #java