Advanced Java theory and code

Implement functional interfaces using lambda expressions to replace anonymous inner classes.

Distinguish and apply the four types of method references (static, instance, constructor, arbitrary object).

Utilize common built-in functional interfaces from java.util.function (e.g., Predicate, Function, Consumer, Supplier).

Analyze the behavior of closures and effectively final variables within lambda expressions.

Create streams from collections, arrays, and generator functions (generate, iterate).

Chain intermediate operations like filter, map, flatMap, and sorted to build a data pipeline.

Apply terminal operations to produce a result, including forEach, collect, and reduce.

Use Collectors to group, partition, and summarize data from a stream.

Use the Optional class to safely handle potentially absent values, especially within stream pipelines.

Create custom checked and unchecked exception hierarchies for domain-specific error handling.

Implement the try-with-resources statement with custom AutoCloseable resources.

Use multi-catch blocks to handle multiple exception types in a single catch clause.

Apply exception chaining to wrap and re-throw exceptions while preserving the original cause.

Compare classic I/O streams with NIO.2 APIs and identify appropriate use cases for each.

Perform common file operations (create, copy, move, delete) using the Path and Files classes.

Traverse directory trees and find files using Files.walk() and Files.find().

Use ByteBuffer and FileChannel for efficient, memory-mapped file I/O operations.

Create and start threads using the Thread class and Runnable interface, and describe the thread lifecycle.

Prevent race conditions in multithreaded code using synchronized blocks and methods.

Implement inter-thread communication using wait(), notify(), and notifyAll().

Explain and resolve a deadlock scenario in a multithreaded application.

Apply the 'volatile' keyword to ensure visibility of variable changes across threads.

Manage thread lifecycle and task execution using the ExecutorService framework.

Submit asynchronous tasks using Callable and retrieve results using Future.

Compose dependent asynchronous tasks using CompletableFuture methods like thenApply and thenCompose.

Combine results from multiple CompletableFutures using allOf or anyOf.

Handle exceptions in an asynchronous pipeline using CompletableFuture.

Use ConcurrentHashMap as a high-performance, thread-safe alternative to synchronized Maps.

Implement the producer-consumer pattern using a BlockingQueue.

Use CountDownLatch to synchronize one or more threads waiting for a set of operations to complete.

Use Semaphore to control concurrent access to a limited number of resources.

Apply ReentrantLock for more flexible locking compared to the synchronized keyword.

Describe the purpose of key JVM memory areas: Heap, Stack, and Metaspace.

Explain the fundamental process of garbage collection, including generational GC.

Demonstrate the Java class loading delegation model with a code example.

Tune basic JVM memory settings using -Xms and -Xmx command-line flags.

Interpret basic garbage collection logs to identify potential performance issues.

Inspect classes, methods, and fields at runtime using the Reflection API.

Create object instances and invoke methods dynamically using reflection.

Define custom annotations with appropriate retention and target policies.

Process custom annotations at runtime to alter program behavior.

Implement a simple object validation framework using a custom annotation and reflection.

Implement a thread-safe Singleton pattern using a static block or enum.

Use the Builder pattern to construct complex objects with immutable state.

Apply the Factory Method pattern to defer object instantiation to subclasses.

Implement the Strategy pattern using functional interfaces and lambdas for flexible algorithms.

Apply the Decorator pattern to dynamically add responsibilities to objects.

Use records to define immutable data carrier classes with minimal boilerplate code.

Apply sealed classes and interfaces to create explicitly restricted class hierarchies.

Simplify code using pattern matching for instanceof.

Write more expressive conditional logic using switch expressions.