Live-Coding zu Java 11 Migration und Local Variable Type Inference

Nicolai Parlog


To JAR Hell And Back - A Live Migration to Java 11

I’m sure you’ve heard about compatibility issues with upgrading to Java 9 and beyond, but did you try it yourself yet? This live coding session starts with a typical Java 8 application and runs up against and eventually overcomes the common hurdles:

  • build system configuration
  • dependency analysis with jdeps
  • dependencies on internal APIs and Java EE modules
  • split packages

To get the most out of this talk, you should have a good understanding of the module system basics - afterwards you will know how to approach your application’s migration to Java 9 and the module system.

Fun with var

Since Java 10 you can use var to let the compiler infer a local variable’s type:

var users = new ArrayList<User>()

And that’s pretty much it, right? Surprisingly, no! There are a lot of details to consider…

  • is this JavaScript?!
  • how exactly is the type inferred?
  • where can I use var and what should I look out for?
  • won’t this lead to unreadable code?

After this live-coding deep dive into var, you’ll know all about Java 10’s flagship feature.


Nicolai Parlog (@nipafx) is Java developer, blogger, author, YouTuber and trainer.

Folien / Video(s)

 Folien Teil 1
 Demos Teil 1
 Folien Teil 2

Eine Veranstaltung des iJUG e.V., organisiert durch die JUG Darmstadt.