Choosing the Right Java Version: 8, 11, or 17

Java 8, Java 11, and Java 17 are the most widely used LTS (Long-Term Support) versions of Java. Below is a detailed comparison of these versions in terms of features, performance, and usability.

Quick Summary

Feature	Java 8	Java 11	Java 17
Release Year	2014	2018	2021
LTS (Long-Term Support)	Yes	Yes	Yes
Functional Programming	Introduced (Lambda, Streams)	Enhanced	Enhanced
Garbage Collection (GC)	Parallel GC	G1 GC (default)	G1 & ZGC improvements
Performance	Moderate	Faster	Much faster
Modularization	No	JPMS introduced	Enhanced
String API Enhancements	No	Yes	More Improvements
HttpClient API	No	Introduced	Improved
Switch Expressions	No	No	Introduced
Pattern Matching	No	No	Introduced
Sealed Classes	No	No	Introduced
Removed Deprecated Features	No	Java EE, CORBA removed	More removals

Java 8 (2014) – The Most Popular Version

Java 8 was a revolutionary update that introduced functional programming concepts to Java.

Key Features in Java 8

• Lambda Expressions – Enables functional-style programming.
• Stream API – Efficient collection processing.
• Default & Static Methods in Interfaces – Backward-compatible method additions.
• Optional Class – Helps avoid NullPointerException.
• New Date & Time API (java.time) – Replaces the old java.util.Date.
• Collectors & Reduce Operations – Helps in aggregation operations.

Example – Using Stream API & Lambda

import java.util.Arrays;
import java.util.List;
import java.util.stream.Collectors;

public class Java8Example {
    public static void main(String[] args) {
        List names = Arrays.asList("Alice", "Bob", "Charlie");

        // Convert all names to uppercase using Stream API
        List upperCaseNames = names.stream()
                                           .map(String::toUpperCase)
                                           .collect(Collectors.toList());

        System.out.println(upperCaseNames);
    }
}

Limitations of Java 8

• No built-in HTTP client (Still relies on HttpURLConnection).
• No modularization (Large monolithic JARs).
• Lacks better garbage collection techniques.

Java 11 (2018) – The Next Big LTS Upgrade

Java 11 was the first LTS version after Java 8 and introduced significant improvements.

Key Features in Java 11

• New HTTP Client API (java.net.http) – Supports HTTP/2 and WebSockets.
• String API Enhancements – New methods like isBlank(), lines(), strip(), etc.
• Garbage Collector (G1 GC as Default) – Improved memory management.
• Removed Java EE & CORBA Modules – To make Java more lightweight.
• Local-Variable Type Inference (var) – Introduced in Java 10, continued in Java 11.

Example – Using New HTTP Client API

import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.net.URI;

public class HttpClientExample {
    public static void main(String[] args) throws Exception {
        HttpClient client = HttpClient.newHttpClient();
        HttpRequest request = HttpRequest.newBuilder()
                .uri(URI.create("https://www.example.com"))
                .build();
        
        HttpResponse response = client.send(request, HttpResponse.BodyHandlers.ofString());
        System.out.println(response.body());
    }
}

Performance Enhancements

• Better Garbage Collection (G1 GC as default).
• Startup Performance Improvements.
• Reduced Memory Footprint (Better resource management).

Limitations of Java 11

• Still lacks features like switch expressions and pattern matching.
• JPMS (Java Module System) adoption was complex for legacy projects.

Java 17 (2021) – The Latest LTS Version

Java 17 is the next major LTS release, with improved performance, new features, and better garbage collection.

Key Features in Java 17

• Sealed Classes – Restricts which classes can extend a given class.
• Pattern Matching for Switch – Simplifies conditional statements.
• Better Garbage Collection (ZGC & G1 Enhancements).
• Enhanced Random Number Generators (RandomGenerator).
• MacOS AArch64 Support – Better ARM architecture support.
• Removed Obsolete Features – Deprecated Java 8 and 11 APIs removed.

Example – Using Pattern Matching in Java 17

public class PatternMatchingExample {
    public static void main(String[] args) {
        Object obj = "Hello, Java 17!";

        if (obj instanceof String str) {  // Pattern Matching
            System.out.println(str.toUpperCase());
        }
    }
}

Performance Enhancements

• ZGC & G1 GC Optimized – Faster memory management.
• Better startup time & reduced footprint.
• Supports native memory tracking for better monitoring.

Limitations of Java 17

• Some deprecated APIs are completely removed, breaking backward compatibility.
• Legacy applications need refactoring to leverage new features like modularization.

Java 8 vs Java 11 vs Java 17 – Feature Comparison

Feature	Java 8	Java 11	Java 17
Lambda & Functional Interfaces	Yes	Yes	Yes
Stream API	Yes	Enhanced	Enhanced
Optional Class	Yes	Yes	Yes
String API Enhancements	No	Yes	More Methods
New HTTP Client API	No	Introduced	Improved
Switch Expressions	No	No	Yes
Pattern Matching	No	No	Yes
Sealed Classes	No	No	Yes
Garbage Collection	Parallel GC	G1 GC (default)	G1 & ZGC Optimized
Modularization (JPMS)	No	Yes	Improved
Removed Deprecated Features	No	Java EE, CORBA	More Deprecated APIs Removed

Which Java Version Should You Choose?

• If you are maintaining old applications → Java 8 (but consider upgrading).
• For enterprise stability → Java 11 (LTS) is widely used.
• For the latest features and best performance → Java 17 (LTS) is recommended.

Conclusion

• Java 8 introduced functional programming (Lambda, Streams, etc.).
• Java 11 brought modern APIs (HTTP Client, String Enhancements, GC Improvements, etc.).
• Java 17 is the most efficient LTS version, with sealed classes, pattern matching, and better GC performance.

For new projects, use Java 17 (LTS). For production stability, use Java 11 (LTS). Java 8 is becoming outdated.