One feature of Scala is it reuse Java's Exception class hierarchies, but much easier to use. For one thing, it treats Exception as "unchecked" just like RuntimeException, which I think one of the reason it causes Java to be unnecessary verbose. For example when opening a file stream, one way Java can do it is:

public void doFile(File file) throws FileNotFoundException, IOException {  
  FileInputStream fins = null;
try{
fins = new FileInputStream(file);
//process it.
}finally{
if(fins != null){ fins.close(); }
}
}

But in Scala equivalent can be done as follow:
def doFile(file: File): Unit = {  
  val fins = new FileInputStream(file)
try{
//process it.
}finally{
fins.close
}
}

In Scala, you don't need to predefine the "fins" to null then try it, and then check to close in finally block, because if FileInputStream failed, an FileNotFoundException instance will be thrown out of the method, before reaching to the try block. In addition, the Scala user of the doFile method do NOT need to invoke it inside a try/catch block, while Java requires it. This is possible because Exception, or any subclasses are "uncheck" as default in Scala. This mean that the exception will keep throw to next stack frame until it finds a "catcher". If none are found, it will exit main at the end.

Views: 40

Happy 10th year, JCertif!

Notes

Welcome to Codetown!

Codetown is a social network. It's got blogs, forums, groups, personal pages and more! You might think of Codetown as a funky camper van with lots of compartments for your stuff and a great multimedia system, too! Best of all, Codetown has room for all of your friends.

When you create a profile for yourself you get a personal page automatically. That's where you can be creative and do your own thing. People who want to get to know you will click on your name or picture and…
Continue

Created by Michael Levin Dec 18, 2008 at 6:56pm. Last updated by Michael Levin May 4, 2018.

Looking for Jobs or Staff?

Check out the Codetown Jobs group.

 

Enjoy the site? Support Codetown with your donation.



InfoQ Reading List

Pinecone Brings AI Agents Directly to Enterprise Data with Microsoft OneLake Integration

Pinecone has announced a new integration between its Nexus knowledge engine and Microsoft OneLake, aiming to fundamentally change how enterprise AI agents access and reason over corporate data.

By Craig Risi

Run Untrusted AI Agent Code Safely with Azure Container Apps Sandboxes

Microsoft has announced the public preview of Azure Container Apps Sandboxes. This new ARM resource type is Microsoft.App/SandboxGroups, runs untrusted code generated by agents in hardware-isolated environments. Each sandbox starts from an OCI disk image in less than a second. It can scale to thousands of instances at once and costs nothing when idle.

By Claudio Masolo

Presentation: Moving Mountains: Migrating Legacy Code in Weeks instead of Years

David Stein shares how to rethink large-scale architectural migrations using AI. He discusses ServiceTitan's "assembly line" pattern, explaining how decomposing legacy codebase refactoring into standardized tasks can achieve massive parallelization. He highlights the critical role of programmatically rigid validation loops to eliminate LLM hallucinations and accelerate engineering agility.

By David Stein

Podcast: Craig McLuckie on Culture as a Team's Operating System in the AI Era

In this podcast, Shane Hastie, Lead Editor for Culture & Methods spoke to Craig McLuckie, co-creator of Kubernetes and CEO of Stacklok, about the impact of AI coding tools on open source communities and engineering teams, designing deliberate organisational culture, and navigating evolving career paths for engineers in the age of AI.

By Craig McLuckie

Oracle's OpenJDK Bans Generative AI Contributions While Oracle's GraalVM Allows Them

Two related, Oracle-backed projects published opposing policies on open-source contributions created with generative AI: The OpenJDK Governing Board approved an interim policy prohibiting such contributions, while the Coding Assistants policy from GraalVM permits them. Both projects require contributors to sign the same Oracle Contributor Agreement (OCA) for intellectual property.

By Karsten Silz

© 2026   Created by Michael Levin.   Powered by

Badges  |  Report an Issue  |  Terms of Service