The Oracle 1Z0-821 exam is a comprehensive assessment designed to evaluate your Java programming skills and knowledge. It covers a wide range of topics, from the fundamentals of Java programming to more advanced concepts like generics, collections, and exception handling. You'll also delve into object-oriented programming principles, including inheritance, polymorphism, and abstraction. The exam tests your understanding of Java's syntax, data types, operators, and control flow structures. Additionally, it assesses your ability to work with classes and objects, create and use methods, and implement basic input/output operations. Advanced topics such as lambda expressions, streams, and functional interfaces are also part of the curriculum. Furthermore, the exam expects you to demonstrate proficiency in designing and implementing algorithms, as well as understanding and applying design patterns. Lastly, you'll need to showcase your skills in debugging and testing Java code, ensuring its reliability and performance.