Key topics covered include object-oriented programming (OOP) principles such as inheritance, polymorphism, encapsulation, and abstraction. Candidates must demonstrate expertise in designing modular and reusable software architectures using abstract classes, interfaces, and design patterns like Singleton, Factory, and Dependency Injection.

The test also focuses on memory management and garbage collection, where candidates are assessed on heap and stack allocation, garbage collection strategies, and performance optimization techniques to prevent memory leaks and improve application efficiency.

Advanced topics include functional programming and Java Streams, where candidates are tested on lambda expressions, functional interfaces, and stream operations for efficient data processing. The test may also include reflection and annotations, evaluating candidates' ability to inspect and manipulate classes, methods, and fields dynamically.

The test further assesses knowledge of JVM internals and performance tuning, covering Just-In-Time (JIT) compilation, class loading, and profiling tools used for optimizing Java applications. Understanding network programming and RESTful APIs is also crucial for building modern web-based and distributed applications.