Test Java Functional Programming (Lambda & Stream) skills

Based on the comprehensive guide you've provided, here's a structured approach to studying Java's functional programming features, specifically focusing on lambda expressions, method references, and the Stream API:

1. Understand Lambda Expressions:

   • Learn the syntax of lambda expressions.
   • Practice using the arrow (->) operator for concise lambda expressions.
   • Study the requirements for an interface to be a Functional Interface (@FunctionalInterface).
   • Convert anonymous inner class code to Lambda expression for practice.
   • Understand this context differences between anonymous inner classes and lambda expressions.
   • Learn how local variables can be captured by lambda expressions.

2. Master Lambda Expressions:

   • Deep dive into the types of lambda expressions: functional methods, constructor invocations, and instance method calls.
   • Practice writing lambda expressions for various scenarios.

3. Explore Method References:

   • Learn about the double colon (::) operator used in method references.
   • Understand the four types of method references:
     • Method Reference to Constructor
     • Method Reference to Static Method
     • Method reference to an Instance Method of a Particular Object
     • Method Reference to an Instance Method of an Arbitrary Object of a Particular Type
   • Practice distinguishing between static and instance method references.

4. Study Functional Interfaces:

   • Get familiar with the four most important built-in functional interfaces: Supplier, Consumer, Predicate, and Function.
   • Understand the default methods provided by these interfaces, such as chaining (andThen) for Function and Predicate, and operations like or, and, negate for Predicate.

5. Learn Stream API:

   • Understand the Generic Stream interface and its primitive counterparts.
   • Practice creating sequential streams.
   • Learn important methods of the Stream interface, such as filtering, mapping, reducing, sorting, collecting, and terminal operations like forEach, collect, etc.
   • Explore the Generic Optional class and its use with Streams.

6. Utilize Parallel Streams:

   • Understand how to create parallel streams.
   • Practice using stream() and parallelStream() methods of Collection interfaces.
   • Learn about the behavior of different methods like forEach, reduce, forEachOrdered, and findFirst when used with parallel streams.

7. Practice with Examples:

   • Implement examples provided in the guide to reinforce understanding.
   • Experiment with different scenarios and complex use cases.

8. Take Practice Tests:

   • Use the practice tests available in the guide to assess your understanding and identify areas needing improvement.
   • Take advantage of features like pausing, retaking, and marking questions for review.

9. Review and Reflect:

   • After completing each test, review the answers and understand why certain options are correct or incorrect.
   • Revisit sections that were challenging during the test.

10. Stay Updated:

    • Keep up with the latest updates in Java to ensure you're familiar with any new features or changes that could affect functional programming concepts.

By following this structured approach, you can systematically improve your understanding and proficiency in Java's functional programming capabilities. Remember to take your time, practice regularly, and apply these concepts in real-world scenarios to solidify your knowledge.