Code with Java 21 is a practical journey through one of the world’s most prolific computer programming languages. It is meant to help readers build up their knowledge of common Java programming constructs, data structures, and engineering paradigms. Filled with real-world examples, this book aims to build the reader’s understanding of building software applications with Java. Seasoned Java developers should buckle in as this book takes a hands-on approach to leveraging popular Java frameworks like Spring and Vaadin to build rich, feature-filled web applications. It also covers building powerful data-driven applications on enterprise-grade databases like PostgreSQL and Apache Cassandra®. This book will also show how to use Java to animate with colorful graphics and even build a simple arcade game.