Scalable Human Blog

Java 11 brought with it many new features and improvements, but one that caught the attention of many developers was the ability to launch single-file source-code programs directly. This feature simplifies the process of testing and running small Java applications and scripts, without the need to compile them explicitly. Let’s delve into this novel capability and see how it can be leveraged.

Understanding the Feature

Prior to Java 11, running a Java program required you to first compile the source code into bytecode using the javac command, and then execute it using the java command. With Java 11, you can directly run the .java file using the java command. The JVM takes care of compiling and executing it in one step.

This feature is primarily aimed at enhancing the developer’s experience, particularly for scripting or prototyping, where quick execution without intermediate steps is preferred.

How to Use It

Suppose you have a single-file Java program named HelloWorld.java:

public class HelloWorld { public static void main(String[] args) { System.out.println("Hello, World!"); } }

With Java 11, you can directly run this file using:

java HelloWorld.java

The output will be:Copy code

Hello, World!

No explicit compilation step is needed!

Benefits

1. Simplification: This feature simplifies the process of writing and testing small Java programs, making Java more suitable for scripting or rapid prototyping.
2. Enhanced Developer Experience: By reducing the steps required to run a program, this feature provides a smoother development experience, particularly for newcomers to the language.
3. Flexibility: It encourages experimentation and interactive development by allowing you to quickly test snippets of code.

Limitations

• This feature is intended for single-file programs. It’s not suitable for larger projects with multiple interdependent files.
• The executed file must contain the main method, as it acts as the entry point for execution.

Conclusion

Java 11’s ability to launch single-file source-code programs represents a significant stride towards enhancing the developer’s experience and making Java more approachable for scripting and prototyping. While it’s not meant to replace traditional compilation and execution for complex projects, it offers an efficient and hassle-free way to test, debug, and run smaller pieces of code.

Developers keen on quick iterations, learning Java, or those working on small-scale applications can greatly benefit from this feature. So, why not give it a try? It might just change the way you interact with Java!

📚 Further Reading & Related Topics

If you’re exploring Java 11’s feature to launch single-file source code programs, these related articles will provide deeper insights:

• Java 16 and the Standardization of Records: Simplifying Data Classes – Learn how Java’s introduction of records in later versions, including Java 16, complements the simplicity and ease of working with single-file programs in Java.

• Mastering Unit Testing in Spring Boot: Best Practices and Coverage Goals – Discover how Java 11’s simplified approach to running source code can be extended to unit testing and application testing for faster development cycles.