I am excited to share one of the fundamental Java concepts — Difference between Array and ArrayList💡 *Difference between Array vs ArrayList in Java Understanding the difference between Array and ArrayList is important for every Java developer 🔹 Array: * Fixed size (once created, cannot be changed) * Can store primitive data types (int, char, etc.) * Faster performance * Less flexible 🔹 ArrayList: * Dynamic size (can grow/shrink) * Stores only objects (not primitive directly) * More flexible and easy to use * Part of Java Collection Framework * Conclusion: Use Array when size is fixed and performance is critical. Use ArrayList when flexibility and dynamic resizing are needed. #Java #Programming #Learning #Coding #Developer

MaskMe Java Library: Annotation-BasedData Masking for JAVA Applications 🎭 MaskMe is a lightweight, modern, annotation-based Java library for dynamic masking of sensitive data in objects—supporting both Java classes and records. Framework-agnostic, MaskMe integrates seamlessly with Spring, Quarkus, or pure Java. Enjoy conditional masking based on roles, environment, or custom logic, thread safety for web apps, and flexible field referencing. Secure your data with ease—try MaskMe today! #Java #DataMasking #MaskMe #JavaSecurity #SpringBoot #Quarkus #AnnotationBased #OpenSource #JavaLibrary #Privacy #WebSecurity #epam #EPAMPoland #insidepam #lifeatepam #epamerslifestyle #epamoffice #epamwarsaw #EPAMSystems #warsaw #poland #informationtechnology #programming #workspace #softwareengineer #javadeveloper #europe #computerscience #softwaredeveloper #JavaRAG #JUGLodz #TechEvents #poland #technology #software #engineering #tech #TechTalk #TechDemo #SpringFramework #2026Tech #JavaAI #GenerativeAI #JavaDevelopment #JavaProjects

Polymorphism in Java Polymorphism is one of the core concepts of Object-Oriented Programming (OOP). It allows a single method name to perform different tasks based on the input. Types of Polymorphism in Java: 1. Compile-Time Polymorphism (Static Binding)→ Achieved using Method Overloading. 2. Run-Time Polymorphism (Dynamic Binding)→ Achieved using Method Overriding. Today I Learned: 1. Compile-Time Polymorphism in Java Today I explored the concept of Compile-Time Polymorphism, also known as Method Overloading in Java. It allows a class to have multiple methods with the same name but different parameters (type, number, or order). The method call is resolved at compile time, which makes the execution faster and more efficient. Example: Calculator using Method Overloading. This concept improves code readability and helps in writing flexible and reusable code. #Java #OOP #Polymorphism #MethodOverloading #LearningJourney

Day 11 of Java I/O Journey Today I focused on Exception Handling in Java ⚠️ 🔹 Types of Exceptions • Checked Exceptions → Handled at compile time (e.g., IOException, SQLException) • Unchecked Exceptions → Occur at runtime (e.g., NullPointerException, ArrayIndexOutOfBoundsException) 🔹 Key Keywords • try → Wrap code that may cause an exception • catch → Handle specific exceptions • finally → Executes important code (always runs) 🔹 What I Learned ✔ Use multiple catch blocks for different exceptions ✔ Always log errors for better debugging ✔ Create custom exceptions for cleaner and more meaningful code 💡 Exception handling makes your program more robust and reliable. Learning not just to write code, but to handle errors like a pro ⚡ How do you usually handle exceptions in your projects? #Java #JavaIO #Programming #Coding #SoftwareDevelopment #Developers #LearningInPublic #100DaysOfCode #CodingJourney #JavaDeveloper #BackendDevelopment #TechSkills #Hariom #HariomKumar #Hariomcse

🚀 Java Concept of the Day: ConcurrentHashMap in Java When multiple threads access a normal HashMap simultaneously, it may cause data inconsistency. To solve this issue, Java provides ConcurrentHashMap. ✅ Thread-safe collection ✅ Better performance than Hashtable ✅ Allows concurrent read/write operations ✅ Used in high-performance backend applications 📌 Example: ConcurrentHashMap<Integer, String> map = new ConcurrentHashMap<>(); map.put(1, "User1"); map.put(2, "User2"); System.out.println(map.get(1)); 💡 Real-time Use Case: Used for caching, session management, shared data in multi-threaded applications. 💬 Interview Question: Difference between HashMap, Hashtable, and ConcurrentHashMap? #Java #JavaDeveloper #Multithreading #BackendDevelopment #Programming #Coding

In Java, handling dates and times has evolved significantly. While older versions used java.util.Date and java.util.Calendar, modern development uses the java.time package, which is more robust and easier to use. Formatting and Parsing To convert a date object into a readable String (or vice versa), you use the DateTimeFormatter class. ✅ yyyy-MM-dd → 2026-03-31 ✅ dd/MM/yyyy → 31/03/2026 ✅ hh:mm a → 12:50 PM Always use DateTimeFormatter for thread-safe parsing and formatting. Your future self (and your team) will thank you! Special Thanks to Anand Kumar Buddarapu #JavaTips #CleanCode #Programming #Developers #TechCommunity #JavaDeveloper

🚀 Java Streams Example: Extract First Letter of Each Word Given a string: String input = "Hello Java Program"; Output: HJP Java Stream Solution: import java.util.Arrays; public class FirstLetterOfWords { public static void main(String[] args) { String input = "Hello Java Program"; String result = Arrays.stream(input.split("\\s+")) .map(word->word.substring(0,1)) .collect(Collectors.joining()); System.out.println(result); } } Output: HJP Using Java Streams makes string manipulation clean and readable. #Java #JavaStreams #Coding #Programming #Developers #BackendDevelopment

🚀 Multithreading in Java: Thread vs Runnable Multithreading is a core concept in Java that enables concurrent execution of tasks, improving application performance and responsiveness. What is a Thread? A thread is a lightweight unit of execution within a process. 🔹Creating a Thread using Thread Class This approach involves extending the Thread class and overriding the run() method. Example: class MyThread extends Thread { public void run() { System.out.println("Thread is running"); } } MyThread t1 = new MyThread(); t1.start(); 🔹 Creating a Thread using Runnable Interface This approach involves implementing the Runnable interface and passing it to a Thread object. Example: class MyRunnable implements Runnable { public void run() { System.out.println("Runnable is running"); } } Thread t2 = new Thread(new MyRunnable()); t2.start(); ⚡ Key Differences: ✔ Thread Class Uses inheritance Limits class extension (Java does not support multiple inheritance) ✔ Runnable Interface Uses interface implementation Provides flexibility to extend other classes Preferred in modern Java applications #Java #Multithreading #Thread #Runnable #JavaDeveloper #Programming #SoftwareEngineering #BackendDevelopment #DevelopersIndia #InterviewPreparation #Tech #Coding

🚀 Understanding HashMap Internal Working in Java Ever wondered how Java’s HashMap gives such fast performance? 🤔 Here’s a quick breakdown: 🔹 Every key goes through hashCode() to generate a hash value 🔹 This hash is converted into an index (bucket location) 🔹 Data is stored in an array of buckets 🔹 In case of collision, multiple elements are stored using LinkedList 🔹 From Java 8 onwards, heavy collisions are handled using a Red-Black Tree ⚡ Average Time Complexity: O(1) 📉 Worst Case: O(log n) (after tree conversion) 💡 Important Concepts to Remember: ✔ Load Factor (0.75) ✔ Rehashing & Resizing ✔ Treeify Threshold (8 nodes) Understanding these internals helps in writing efficient code and cracking Java interviews 💯 #Java #HashMap #Programming #JavaDeveloper #InterviewPreparation