Java 8 FAQ: Top Questions

Java 8 is one of the most significant updates in the Java programming language. It introduced a number of new features aimed at making Java more expressive, compact, and functional.

🚀 Key Features Introduced:

• Lambda Expressions: Enables functional programming with concise syntax.
• Functional Interfaces: Interfaces with a single abstract method, used for lambda targets.
• Stream API: Processes collections of data in a functional style.
• Optional Class: Avoids null pointer exceptions by representing optional values.
• Default & Static Methods: Allows interfaces to have default implementations.
• New Date and Time API: Modern, immutable, and timezone-aware date/time handling in java.time.
• Method References: Enables cleaner syntax for calling methods directly.
• CompletableFuture API: Supports asynchronous programming with futures and callbacks.

🧠 Why These Matter:

• Encourages cleaner, more expressive code.
• Reduces boilerplate (especially for collections and threading).
• Improves readability and maintainability.
• Brings Java closer to modern programming paradigms like reactive and functional programming.

📘 Code Snippets:

// Lambda Expression Example
List names = Arrays.asList("Alice", "Bob", "Charlie");
names.forEach(name -> System.out.println(name));

// Stream API Example
List filtered = names.stream()
                             .filter(n -> n.startsWith("A"))
                             .collect(Collectors.toList());

// Optional Example
Optional name = Optional.ofNullable(null);
System.out.println(name.orElse("Default"));

// Date API
LocalDate today = LocalDate.now();
System.out.println(today.getYear());

🛠️ Use Cases:

• Modernizing legacy applications
• Building microservices with less boilerplate
• Writing expressive and safe collection pipelines
• Better handling of asynchronous code

📚 Summary:

Java 8 marked a major shift in how Java code is written. With a strong emphasis on functional programming, clean syntax, and robust APIs, it laid the groundwork for modern enterprise Java applications.