Java SE 21 Developer Study Guide

This is the e-book version of the book that you can read online. Prepare for the Java 21 certification exam (Exam 1Z0-830) with this comprehensive study guide. This book will give you the knowledge and skills necessary to pass the exam and gain a deep understanding of Java's core features and advanced topics. Each chapter provides in-depth explanations, practical examples, and best practices to reinforce your learning and help you grasp the key concepts. Additionally, at the end of each chapter, you'll find a summary of key points and practice questions designed to test your understanding and prepare you for the certification exam. With this guide, you will: Develop a solid foundation in object-oriented programming concepts, including classes, objects, inheritance, and polymorphism Learn how to effectively use records and enums to create immutable data carriers and predefined constants Understand Java's data handling capabilities, including primitive types, reference types, and the Collections Framework Explore control flow structures and techniques for managing program execution flow efficiently Discover functional programming with lambda expressions, method references, and the Stream API Understand Java's concurrency and multithreading capabilities, including thread creation, synchronization, virtual threads, and the Concurrency API Become proficient in the Date/Time API for handling dates, times, and durations with ease Learn how to perform efficient file I/O operations using the NIO.2 API Explore the Java Platform Module System (JPMS) for creating modular and encapsulated applications Discover Java's localization capabilities for creating internationalized applications By the end of this book, you will be well-prepared to tackle the Java 21 certification exam (Exam 1Z0-830) with confidence.