The document outlines the key features introduced in various Java versions from 5 to 23, detailing enhancements such as generics, lambda expressions, and the module system. Each feature is described with a short overview and a code snippet example. The document also hints at future speculated improvements in performance and programming paradigms.

1. Mohammed Fazuluddin | Technical Architect
Java Version(v5 -v23) Features

2. Feature Short Description Example Code Snippet
Generics
Enables type safety in collections and eliminates type
casting.
List<String> list = new ArrayList<>(); list.add("Hello"); String s =
list.get(0);
Enhanced for Loop Simplifies iteration over collections or arrays. for (String s : list) { System.out.println(s); }
Autoboxing/Unboxing
Automatic conversion between primitives and wrapper
classes.
Integer num = 10; int n = num;
Enums Type-safe constants using enumeration types. enum Day { MONDAY, TUESDAY; } Day today = Day.MONDAY;
Varargs
Enables methods to accept variable numbers of
arguments.
void printArgs(String... args) { for (String s : args) {
System.out.println(s); } }

3. Feature Short Description Example Code Snippet
Scripting API Integration with scripting languages like JavaScript.
ScriptEngine engine = new
ScriptEngineManager().getEngineByName("JavaScript");
engine.eval("print('Hello World');");
Pluggable Annotation API Allows processing custom annotations at compile-time. @interface CustomAnnotation { String value(); }

4. Version-7
Feature Short Description Example Code Snippet
Try-with-resources
Simplifies resource management by auto-closing
resources.
try (BufferedReader br = new BufferedReader(new
FileReader("file.txt"))) { System.out.println(br.readLine()); }
Switch with Strings Adds support for string-based switch statements. switch (value) { case "A": System.out.println("A"); break; }
Diamond Operator Reduces boilerplate code when instantiating generics. List<String> list = new ArrayList<>();
NIO.2 Enhances file handling, including the Path API. Path path = Paths.get("file.txt"); Files.readAllLines(path);

5. Version-8
Feature Short Description Example Code Snippet
Lambda Expressions Adds functional-style programming to Java. list.forEach(item -> System.out.println(item));
Stream API Simplifies processing collections in a functional style. list.stream().filter(s -> s.startsWith("A")).forEach(System.out::println);
Default Methods Enables interface methods with default implementations.
interface MyInterface { default void show() {
System.out.println("Default method"); } }
Date-Time API Introduces a new and improved date-time library. LocalDate date = LocalDate.now();
Optional Avoids NullPointerException by wrapping nullable values.
Optional<String> opt = Optional.ofNullable(value);
opt.ifPresent(System.out::println);

6. Version-9
Feature Short Description Example Code Snippet
Module System Adds modularity for better code organization. module com.example { requires java.base; }
JShell Interactive REPL for Java code execution. jshell> System.out.println("Hello, World!");
Improved Stream API Adds methods like takeWhile, dropWhile, and iterate. Stream.of(1, 2, 3).takeWhile(x -> x < 3).forEach(System.out::println);

7. Version-10
Feature Short Description Example Code Snippet
Local Variable Type Inference Introduces var for inferred variable types. var list = new ArrayList<String>();

8. Version-11
Feature Short Description Example Code Snippet
HTTP Client API Simplifies making HTTP requests.
HttpClient client = HttpClient.newHttpClient(); HttpResponse<String>
response = client.send(request, BodyHandlers.ofString());
String Methods Adds useful string operations like isBlank, lines, and strip. "Hello ".strip();
Running Single File Programs
Simplifies running small Java programs without
compilation.
java HelloWorld.java

9. Version-12
Feature Short Description Example Code Snippet
Switch Expressions (Preview)
Simplifies switch statements by making them
expressions.
String result = switch (day) { case MONDAY -> "Start"; default ->
"End"; };
Compact Number Formatting Formats numbers compactly.
NumberFormat nf =
NumberFormat.getCompactNumberInstance(Locale.US,
Style.SHORT); nf.format(1000);

10. Version-13
Feature Short Description Example Code Snippet
Text Blocks (Preview) Simplifies multiline string literals. String json = """ { "key": "value" } """;

11. Version-14
Feature Short Description Example Code Snippet
Record Classes (Preview) Introduces concise classes for immutable data. record Point(int x, int y) { }
Helpful NullPointerExceptions
Provides detailed error messages for null pointer
exceptions.
obj.method(); with NullPointerException showing context.

12. Version-15
Feature Short Description Example Code Snippet
Sealed Classes (Preview)
Restricts which classes can extend or implement a
class/interface.
sealed class Shape permits Circle, Rectangle { }

13. Version-16
Feature Short Description Example Code Snippet
Records (Finalized) Simplified immutable data carriers finalized from preview. record Point(int x, int y) { }
Pattern Matching (Preview) Simplifies type checks in instanceof. if (obj instanceof String s) { System.out.println(s); }

14. Version-17
Feature Short Description Example Code Snippet
Sealed Classes (Finalized) Finalizes sealed classes. sealed class Shape permits Circle, Rectangle { }
Pattern Matching for Switch Adds pattern matching in switch statements. switch (obj) { case String s -> System.out.println(s); }

15. Version-19
Feature Short Description Example Code Snippet
Virtual Threads (Preview) Lightweight threads for better concurrency. Thread.startVirtualThread(() -> System.out.println("Hello"));
Structured Concurrency
Simplifies multithreaded programming with a structured
approach.
try (var scope = new StructuredTaskScope.ShutdownOnFailure()) { }

16. Version-20
Feature Short Description Example Code Snippet
Scoped Values (Preview) Provides a way to safely share data between threads. ScopedValue.newValue();

17. Version-21
Feature Short Description Example Code Snippet
Generational ZGC
Improves performance of the low-latency garbage
collector.
Internally optimized, no user code changes.
String Templates Allows embedding expressions in strings. String result = STR."Value: #{value}";

18. Version-23
Feature Short Description Example Code Snippet
Future Features (Speculated)
Continued enhancements in performance, native support,
and new programming paradigms.
To be announced.