Java 17 Sealed Classes for Stronger Domain Modeling

One subtle difference between #Java and #Rust: in Java, mutating a Map inside computeIfAbsent can compile fine and fail at runtime with a ConcurrentModificationException (or worse, silent issues in older JDKs). In Rust, the same pattern doesn’t even compile — the borrow checker stops you. This is what “safe by design” really means: entire classes of bugs are eliminated before your code ever runs.

This insight from my good friend Andres Santana comes from first-hand experience working at Amazon Web Services (AWS) on large-scale systems. It demonstrates that #Rust has been mistakenly and repeatedly compared to C++, when it should instead be considered as a replacement for higher-level languages like #TypeScript, #Java, #Python and #Go.

🚀 Day 24/180 | #180DaysOfCode 📍 LeetCode | 💻 Java Solved: 2859. Sum of Values at Indices With K Set Bits Used bit manipulation to count the number of set bits in each index and summed the values whose index contains exactly k set bits. ⏱️ Time Complexity: O(n log n) 📦 Space Complexity: O(1) Strengthening understanding of bitwise operations and binary representation through consistent practice. 💪 Consistency continues 🚀 #DSA #LeetCode #Java #CodingJourney #Consistency

Day 84/365 ✔️ Solved LeetCode 26 – Remove Duplicates from Sorted Array using Java. A classic two-pointer problem that looks simple but really tests how well you handle in-place updates. Key takeaways from today: • Leveraged the two-pointer technique • Modified the array in-place with O(1) extra space • Preserved the relative order of elements • Reinforced how sorted arrays simplify logic Consistency > intensity. One problem a day, building strong fundamentals. On to the next 🚀 #Day84 #365DaysOfCode #LeetCode #Java #DSA #TwoPointers #ProblemSolving #Consistency

Today I revised and hand-written detailed notes on some of the most powerful features introduced in Java 8. Java 8 completely changed the way we write code by introducing functional programming concepts, cleaner syntax, and better APIs. Writing notes by hand helps me understand concepts more deeply rather than just reading them. Consistency > Motivation 💪 #Java #Java8 #BackendDevelopment #MCA #LearningJourney 🔹 Lambda Expressions reduce boilerplate code and make implementation of Functional Interfaces concise. 🔹 @FunctionalInterface annotation provides compile-time safety. 🔹 Stream API allows clean data processing using filter(), map(), reduce(), collect() without traditional loops. 🔹 Optional class helps avoid NullPointerException and improves code safety. 🔹 New Date & Time API (java.time) is immutable and thread-safe.

Records in Java are used to create immutable data objects with minimal code. They automatically generate constructors, getters, equals(), hashCode(), and toString(). Unlike traditional bean classes, they eliminate boilerplate and improve readability.Records are best suited for DTOs and data carriers in modern applications. Java 14 → Preview Java 15 → Preview (second iteration) Java 16 → Official release #java #java16 #java17

𝗧𝗵𝗿𝗲𝗮𝗱𝘀 𝗶𝗻 𝗝𝗮𝘃𝗮 Link -> https://lnkd.in/gYBYyshF 🚀 Multithreading in Java – Powering Concurrent Applications Threads in Java enable concurrent execution, allowing multiple tasks to run simultaneously within a single program. By leveraging: Thread class Runnable interface ExecutorService Synchronization & Locks Concurrent utilities We can build high-performance, responsive, and scalable applications. Understanding concepts like race conditions, deadlocks, thread lifecycle, and synchronization is key to writing efficient concurrent code. Multithreading isn’t just about speed — it’s about smart resource utilization. But it also demands careful handling of: ❗ Shared resources ❗ Synchronization ❗ Memory visibility (JMM) Concurrency done right = Performance + Stability.

Spawning more threads doesn’t always mean more performance. Inside a process, Java threads must ultimately run as kernel threads managed by the OS. For years, Java used a 1:1 mapping: one user-level thread per kernel thread. Easy to reason about, but expensive, limited, and painful at scale. Virtual threads change the game onwards version.21 They’re lightweight, JVM-managed and multiplexed over a small pool of kernel threads. Same blocking code, Massive concurrency and Minimal OS load. This is how Java finally made Threads cheap.

Java 17 Pattern Matching in Switch is a Game Changer 🎯 Type casting in switch statements used to be verbose and error-prone. 1- Pattern Matching for Switch You can now switch on the type of an object, not just its value. This eliminates verbose instanceof checks and explicit casting. 2- Guarded Patterns (The when clause) Refine your patterns by adding conditional logic directly to the case label. Note: This specific syntax was refined to when in later versions, but in Java 17, it technically arrived via pattern matching capabilities #Java #Java17 #PatternMatching #CleanCode #JVM

Today, I’m reflecting on Java constructors.These special methods let us initialize objects. There are two main types: default constructors, which have no parameters and provide a baseline setup, and parameterized constructors, which take arguments so we can set values upfront. Constructors really help keep our code organized and expressive. In short, constructor is a special function, which is called implicitly (automatically) at the time of object creation. #JavaConcepts #Constructors #LearningJava #CodeNewbie #TechLearning #DeveloperJourney #ComputerScience