Online Java Compiler and Runner Core Java java Java 21 by devs5003 - May 31, 2025June 16, 20250 Looking for a quick way to compile and execute Java code online without installing JDK? Our free Online Java Compiler lets you write, run, and debug Java programs instantly in your browser: supports Java 21 (latest LTS version)! 👨💻 Try It Now: Online Java Compiler Below 📢 Bookmark this page for quick access whenever you need to test Java code! Why Use This Online Java Compiler? ✅ No Installation RequiredYou don’t need to download JDK or set up IDEs like Eclipse or IntelliJ. Just open your browser and start coding! ✅ Supports Latest Java Version (Java 21)Write and test code with the newest Java features like: Pattern Matching for switch Record Classes, Sealed Classes/Interfaces Virtual Threads (Project Loom) ✅ Beginner-Friendly InterfaceThe simple and clean interface is perfect for learning and
System Design Concepts Tutorial java Microservices System Design by devs5003 - May 25, 2025January 5, 20261 System Design Concepts: A Beginner's Guide Have you ever thought how websites like Facebook handle millions of users at once, or how Netflix streams videos without constant buffering? The secret lies in solid system design. System design is the art and science of building software that can grow, adapt, and survive in the real world. It's about making smart choices when deciding how different parts of a system should work together. Whether you are creating a simple app or the next big social platform, good system design makes the difference between success and failure. I remember when I first tackled system design. It seemed like an overwhelming mix of technical jargon and abstract concepts. But breaking it down into fundamental principles makes it
System Design Interview Questions Practice MCQs java MCQ Microservices System Design by devs5003 - May 14, 2025August 10, 20250 System design interviews have become a critical component of the technical hiring process at top tech companies, especially for mid-level to senior software engineering roles. Unlike coding interviews that focus on algorithms and data structures, system design interviews evaluate a candidate's ability to architect scalable, efficient, and maintainable software systems. In today’s world, where applications must support millions of users, handle large volumes of data, and provide high availability, companies look for engineers who understand distributed systems, microservices architecture, database sharding, caching, message queues, and more. These interviews help assess whether candidates can balance trade-offs between scalability, reliability, performance, and cost. If you want to refresh concepts of System Design first, kindly visit a series of articles on System Design Tutorials. In this
Spring Boot Annotations MCQs Annotations Interview java MCQ Spring Spring Boot Spring Boot 3 by devs5003 - May 7, 2025February 16, 20260 Spring Boot Annotations MCQs Understanding annotations in Spring Boot is essential for any Java developer working on enterprise-grade applications. These annotations simplify configuration, reduce boilerplate code, and help in building robust applications faster. Whether you're preparing for technical interviews, certification exams, or just aiming to solidify your Spring Boot foundation, mastering Spring Boot annotations is non-negotiable. Need to revise annotations first? Read "Spring Boot Annotations Guide." In this article, we will explore a set of Spring Boot Annotations MCQs that cover: Concept-based questions to test your theoretical knowledge Code-based questions to check your practical understanding Scenario-based questions to simulate real-world use cases Each question is carefully created with detailed explanations and covers both correct and incorrect options to help you learn and revise effectively. So,
Java Design Patterns Interview Questions Practice Test MCQs Core Java Design Patterns Interview java Java MCQ by devs5003 - April 22, 2025November 13, 20250 Practice tests are essential to mastering any technology. They help us review topics thoroughly and understand the concepts clearly. In this article, we’ll focus on a Java Design Patterns Interview Questions Practice Test MCQs, including different question types like: Concept-based (testing our theory knowledge), Code-based (checking our coding skills), and Scenario-based (applying knowledge to real-world problems). Each question comes with detailed explanations for both correct and incorrect answers, so we will learn not just what’s right, but also why the other options are wrong. Sometimes, even incorrect answers teach us something useful! Let's go through Java Design Patterns Interview Questions Practice Test MCQs. Java Design Patterns Interview Questions Practice Test MCQs Q#1. (Scenario-Based Question, Single-Select) You have different types of notification systems (Email, SMS,
Java System Design- Hospital Management System Design java Microservices Spring Boot System Design by devs5003 - April 17, 2025February 3, 20263 Java System Design- Hospital Management System The integration of technology through a popular Hospital Management System (HMS) can be a good example that offers a digital solution to automate processes such as patient registration, appointment scheduling, billing, inventory management, and staff coordination. This article talks about the comprehensive system design of a modern HMS, leveraging Java, Spring Boot, and a microservices architecture. This combination ensures scalability, flexibility, and resilience, that makes it an ideal choice for addressing the complex and ever-growing demands of healthcare institutions. With a primary focus on system design, we will explore the architecture, individual components, data management strategies, security measures, deployment considerations, performance optimization, future scalability, and practical implementation details, all with essential diagrams. The Importance of a Modern Hospital
Java 21 Coding Example- Hospital Management System Core Java java Java 21 jdk 20 Programming by devs5003 - April 10, 2025August 21, 20250 This article presents an implementation of a Hospital Management System using Java 21. If we say using Java 21, it means we are free to use all the final features that are available till Java 21. It doesn't matter whether a particular feature belongs to Java 8 or Java 21. The used feature should be available till Java 21. Our focus would be on some progressive features such as sealed classes, records, pattern matching in switch, immutable collections, and formatted string output. Along the way, we’ll also explore how these features simplify code design, improve safety, and enhance readability. The primary target of this article is to practice the most important & latest features of Java in a real world use
Java 21 vs Java 17 vs Java 8 Implementation – Hotel Room Booking System Core Java java Java 17 Java 21 Java 8 by devs5003 - April 3, 2025August 16, 20250 Java 21 vs Java 17 vs Java 8 Implementation Java has offered powerful features with each new version significantly over the years, that enhance developer productivity, code readability, and performance. In this analysis based article, we will explore the Hotel Room Booking System implemented in Java 8, Java 17, and Java 21, and compare how modern Java features simplify development while maintaining backward compatibility. This comparison should also helpful as a practical guide for developers considering migration or simply wanting to leverage modern Java effectively. The Hotel Booking System is a real-world use case that involves Dynamic pricing (room types, discounts), Business rules (membership benefits, seasonal offers) & Concurrency (parallel processing for bulk bookings). In this implementation we will Compare coding styles – from verbose Java 8 to concise
How to Sort List by Date in Java 8 ? java Core Java Java 8 by devs5003 - March 31, 2025January 29, 20260 Sorting a List by Date sometimes becomes a bit tricky. One of the tricky part is how to handle date format and then perform the sorting. In this article 'How to Sort List by Date in Java 8 ?', we will discuss sorting of three types of Dates. These are java.util.Date, java.time.LocalDate and java.time.LocalDateTime. Further, in order to sort the list, we will use three approaches. Using these approaches, we will utilize the new concepts introduced in Java 8. Moreover, these concepts are Lambda Expressions, Method References and Stream API. Additionally, if you want to know how to sort a general list in Java 8, we have separate article on 'How To Sort the List In Java 8?'. Here we will
What are Preview Features in Java? Core Java java by devs5003 - March 24, 2025March 27, 20250 In every new version of Java, one word is definitely seen and that is 'Preview Feature'. Some of us know about it, but some people like beginners don't know. Even if one who knows, there is no proper clarity about it. Therefore, in this article, we will discuss in detail all about 'Preview Features in Java'. Learning Preview Features in Java helps developers stay updated with new improvements before they become permanent. It allows early testing, reduces future migration efforts, and improves coding efficiency. Developers can also provide feedback to shape Java’s future. Understanding these features ensures better decision-making and keeps you ahead in the Java ecosystem. What are Preview Features in Java? Preview features are new functionalities introduced in Java that are