Yan LI’s Post

🚀 Java Evolution: The Road to Java 26 Java isn't just evolving; it's accelerating. If you're still on Java 8 or 11, you're missing out on a decade of massive performance and developer experience wins. Here is the "Big Picture" from the standard of 2014 to the powerhouse of 2026: 🟢 Java 8 (The Pivot) • Lambdas & Streams: Functional programming became a first-class citizen. • Optional: A cleaner way to handle the 'null' problem. 🔵 Java 11 (The Modern Baseline) • var keyword: Local type inference for cleaner code. • New HTTP Client: Modern, asynchronous, and reactive. 🟣 Java 17 (The Clean Slate) • Sealed Classes & Records: Better data modeling and restricted hierarchies. • Text Blocks: Finally, readable multi-line strings for JSON/SQL. 🟠 Java 21 (The Concurrency Leap) • Virtual Threads (Project Loom): Scalability that rivals Go and Node.js. • Pattern Matching for Switch: Expressive, safe logic. 🔴 Java 25 — LTS (The Efficiency Master) • Compact Object Headers: Significant memory reduction across the JVM. • Flexible Constructor Bodies: Running logic before super(). • Scoped Values: A modern, safe alternative to ThreadLocal. ⚪ Java 26 (The Native & Edge Power) • HTTP/3 Support: Leveraging QUIC for ultra-low latency networking. • AOT Object Caching: Drastically faster startup and warm-up times. • G1 GC Improvements: Higher throughput by reducing synchronization overhead. 💡 The Takeaway: Java 25 is the current LTS (Long-Term Support) gold standard, but Java 26 shows where we are heading—near-instant startup and native-level performance. What version are you running in production? Is 2026 the year you finally move past Java 11? ☕️ #Java #SoftwareEngineering #Java26 #BackendDevelopment #JVM #Coding #ProgrammingLife

♻️ Ever wondered how Java manages memory automatically? Java uses Garbage Collection (GC) to clean up unused objects — so developers don’t have to manually manage memory. Here’s the core idea in simple terms 👇 🧠 Java works on reachability It starts from GC Roots: • Variables in use • Static data • Running threads Then checks: ✅ Reachable → stays in memory ❌ Not reachable → gets removed 💡 Even objects referencing each other can be cleaned if nothing is using them. 🔍 Different types of Garbage Collectors in Java: 1️⃣ Serial GC • Single-threaded • Best for small applications 2️⃣ Parallel GC • Uses multiple threads • Focuses on high throughput 3️⃣ CMS (Concurrent Mark Sweep) • Runs alongside application • Reduces pause time (now deprecated) 4️⃣ G1 (Garbage First) • Splits heap into regions • Balanced performance + low pause time 5️⃣ ZGC • Ultra-low latency GC • Designed for large-scale applications ⚠️ One important thing: If an object is still referenced (even accidentally), it won’t be cleaned → which can lead to memory issues. 📌 In short: Java automatically removes unused objects by checking whether they are still reachable — using different GC strategies optimized for performance and latency. #Java #Programming #JVM #GarbageCollection #SoftwareDevelopment #TechConcepts

Reactive Programming in Java Just spent time getting hands-on with Project Reactor (Mono/Flux), and for projects stuck in older versions of Java (pre-21), the strategy is worth the hype. For years, traditional Java (Spring MVC) followed a simple rule: One request = One thread. While straightforward, it leaves threads idle while waiting for databases or external APIs, specifically when dealing with file upload or large data. Reactive programming (Spring WebFlux) is a whole different idea: * Non-blocking I/O: Instead of waiting idly, threads handle other requests while data is in transit. * Elasticity: Handles high concurrency with fewer hardware resources. * Resilience: Built-in backpressure ensures the system doesn’t crash when traffic spikes, as well as great strategies for handling errors Switching from RestTemplate (blocking) to WebClient (non-blocking) with Mono showed me how to compose asynchronous logic declaratively. It feels strange and confusing at first, but the ability to chain operations without blocking threads is incredibly powerful. Although useful before Java 21's Virtual Threads, Spring WebFlux is now almost obsolete, being useful only in very specific cases. Thanks to all users who pointed it out in the comments. If you also want to learn more: https://projectreactor.io #Java #ReactiveProgramming #SpringBoot #WebFlux #SoftwareEngineering #Coding #AlwaysLearning

💡 What I Learned About Java Interfaces (OOP Concept) I explored Interfaces in Java, and realized that they are not just about rules — they play a key role in achieving abstraction, flexibility, and clean design in applications. 🔹 Interfaces & Inheritance Interfaces are closely related to inheritance, where classes implement interfaces to follow a common structure. 🔹 Abstraction Interfaces enable abstraction. Before Java 8, they supported 100% abstraction, but now they can also include additional method types. 🔹 Polymorphism & Loose Coupling Interface references can point to different objects → making code more flexible, scalable, and maintainable. 🔹 Multiple Inheritance Java supports multiple inheritance through interfaces, allowing a class to implement multiple interfaces. 🔹 Functional Interface A functional interface contains only one abstract method. It can be implemented using: 1️⃣ Regular class 2️⃣ Inner class 3️⃣ Anonymous class 4️⃣ Lambda expression 🔹 Java 8 Enhancements Interfaces became more powerful with: ✔️ default methods (with implementation) ✔️ static methods ✔️ private methods ✔️ private static methods 🔹 Variables in Interface All variables are implicitly public static final (constants). 🔹 No Object Creation Interfaces cannot be instantiated, but reference variables can be created. 🚀 Conclusion: Interfaces are a core part of Java OOP that help build scalable, maintainable, and loosely coupled systems. #Java #OOPS #Interfaces #Programming #Learning #Java8 #Coding

In Java versions below 24 virtual threads can pin their carrier platform threads during synchronized blocks or native calls. This prevents the carrier from executing other tasks leading to thread starvation and sub-optimal resource usage. Interesting article on differences between Java 21 and Java 24 in terms how they handle virtual thread pinning. https://lnkd.in/dPpsDYHH

🚀 Day 18 – Java Streams: Writing Cleaner & Smarter Code Today I started exploring Java 8 Streams—a powerful way to process collections. Instead of writing traditional loops: List<Integer> nums = Arrays.asList(1, 2, 3, 4, 5); for (int n : nums) { if (n % 2 == 0) { System.out.println(n); } } 👉 With Streams: nums.stream() .filter(n -> n % 2 == 0) .forEach(System.out::println); --- 💡 What I liked about Streams: ✔ More readable and expressive ✔ Encourages functional style programming ✔ Easy to chain operations (filter, map, reduce) --- ⚠️ Important insight: Streams don’t store data—they process data pipelines 👉 Also: Streams are lazy → operations execute only when a terminal operation (like "forEach") is called --- 💡 Real takeaway: Streams are not just about shorter code—they help write clean, maintainable logic when working with collections. #Java #BackendDevelopment #Java8 #Streams #LearningInPublic

🚀 Exploring the Game-Changing Features of Java 8 Released in March 2014, Java 8 marked a major shift in how developers write cleaner, more efficient, and scalable code. Let’s quickly walk through some of the most impactful features 👇 🔹 1. Lambda Expressions Write concise and readable code by treating functions as data. Perfect for reducing boilerplate and enabling functional programming. names.forEach(name -> System.out.println(name)); 🔹 2. Stream API Process collections in a functional style with powerful operations like filter, map, and reduce. names.stream() .filter(name -> name.startsWith("P")) .collect(Collectors.toList()); 🔹 3. Functional Interfaces Interfaces with a single abstract method, forming the backbone of lambda expressions. Examples: Predicate, Function, Consumer, Supplier 🔹 4. Default Methods Add method implementations inside interfaces without breaking existing code—great for backward compatibility. 🔹 5. Optional Class Avoid NullPointerException with a cleaner way to handle null values. Optional.of("Peter").ifPresent(System.out::println); 💡 Why it matters? Java 8 introduced a functional programming style to Java, making code more expressive, maintainable, and parallel-ready. 👉 If you're preparing for interviews or working on scalable systems, mastering these concepts is a must! #Java #Java8 #Programming #SoftwareDevelopment #Coding #BackendDevelopment #Tech

Why Java 8 (JDK 1.8) Introduced Default, Static & Private Methods in Interfaces Before Java 8, interfaces were purely abstract — We could only declare methods, not define them. But this created a problem If we added a new method to an interface, all implementing classes would break. * Solution in Java 8: Default Methods * Now interfaces can have method bodies using "default" * These methods are automatically inherited by implementing classes 👉 This ensures backward compatibility Example idea: If we add a new method like "communicate()" to an interface, we don’t need to update 100+ existing classes — the default implementation handles it. ⚡ Static Methods in Interfaces ✔ Defined using "static" ✔ Called directly using interface name ✔ Not inherited or overridden 👉 Used when functionality belongs to the interface itself * Private Methods (Java 9 addition) ✔ Used inside interfaces to avoid code duplication ✔ Helps reuse common logic between default/static methods ✔ Not accessible outside the interface *Why all this was introduced? 👉 To make interfaces more flexible 👉 To avoid breaking existing code (backward compatibility) 👉 To reduce duplication and improve code design * Bonus: Functional Interface ✔ Interface with only one abstract method (SAM) ✔ Enables use of Lambda Expressions *Java evolved from “only abstraction” → “smart abstraction with flexibility” #Java #Java8 #OOP #Programming #SoftwareDevelopment #Backend #Coding #TechConcepts

🚀 Day 17/100: Securing & Structuring Java Applications 🔐🏗️ Today was a Convergence Day—bringing together core Java concepts to understand how to build applications that are not just functional, but also secure, scalable, and well-structured. Here’s a snapshot of what I explored: 🛡️ 1. Access Modifiers – The Gatekeepers of Data In Java, visibility directly impacts security. I strengthened my understanding of how access modifiers control data exposure: private → Restricted within the same class (foundation of encapsulation) default → Accessible within the same package protected → Accessible within the package + subclasses public → Accessible from anywhere This reinforced the idea that controlled access = better design + safer code. 📋 2. Class – The Blueprint A class defines the structure of an application: Variables → represent state Methods → define behavior It’s a logical construct—a blueprint that doesn’t occupy memory until instantiated. 🚗 3. Object – The Instance Objects are real-world representations of a class. Using the new keyword, we create instances that: Occupy memory Hold actual data Perform defined behaviors One class can create multiple objects, each with unique states—this is the essence of object-oriented programming. 🔑 4. Keywords – The Building Blocks of Java Syntax Java provides 52 reserved keywords that define the language’s structure and rules. They are predefined and cannot be used as identifiers, ensuring consistency and clarity in code. 💡 Key Takeaway: Today’s learning emphasized that writing code is not enough—designing it with proper structure, access control, and clarity is what makes it professional. 📈 Step by step, I’m moving from writing programs to engineering solutions. #Day17 #100DaysOfCode #Java #OOP #Programming #SoftwareDevelopment #LearningJourney #Coding#10000coders

Is your Java knowledge still stuck in 2014? ☕ Java has evolved massively from version 8 to 21. If you aren't using these modern features, you’re likely writing more boilerplate code than you need to. I’ve been diving into the "Modern Java" era, and here is a quick roadmap of the game-changers: 🔹 Java 8 (The Foundation) 1. Lambda Expressions 2. Stream API 3. Optional 🔹 Java 11 (The Cleanup) 1.New String Methods – isBlank() and repeat() are life-savers. 2.HTTP Client – Finally, a modern, native way to handle REST calls. 3.Var in Lambdas – Cleaner syntax for your functional code 🔹 Java 17 (The Architect's Favorite) 1.Records – One-line immutable data classes. No more boilerplate! 2.Sealed Classes – Take back control of your inheritance hierarchy. 3.Text Blocks – Writing SQL or JSON in Java is no longer a nightmare. 🔹 Java 21 (The Performance King) 1.Virtual Threads – High-scale concurrency with zero overhead. 2.Pattern Matching – Use switch like a pro with type-based logic. 3.Sequenced Collections – Finally, a standard way to get first() and last(). Java isn't "old"—it's faster, more concise, and more powerful than ever. If you're still on 8 or 11, it’s time to explore what 17 and 21 have to offer. #Java #SoftwareEngineering #Backend #Coding #ProgrammingTips #Java21