INRIA/spoon

add support for Java 16

Closed this issue · 11 comments

monperrus commented

What’s coming in Java 16?
https://www.infoworld.com/article/3569150/jdk-16-whats-coming-in-java-16.html#tk.rss_java

MartinWitt commented

https://openjdk.java.net/projects/jdk/16/ as the official link, if somebody wants to read all jeps. From my understanding in December after rampdown phase 1 the feature list is more or less final and we only have to wait for jdt. I would expect records and instanceOf to reach the release state, and a preview for pattern matching (for more about pattern matching you can look at old languages like haskell)

Rohitesh-Kumar-Jain commented

Going through the Java 16 specs, one of the possible changes, I identified is JEP 392: Packaging Tool.

jpackage tool is moved from jdk.incubator.jpackage to jdk.jpackage

slarse commented

Having a quick look at the release notes, it seems like there are only 2 new stable features and 1 new preview feature that require extensions in Spoon. IMO preview features are not worth supporting, though.

Stable features

  • Records (JEP 395)
    • We need a new CtRecord interface to model it
    • Note: This is pure syntactical sugar, it just generates a class with some stuff (e.g. getters for fields, an equals method, a toString, and some other stuff). Pretty much built-in Lombok.
  • instanceof pattern matching (JEP 394)
    • Allows an optional variable to cast to the checked type (if check is successful)
    • E.g. obj instanceof String s instantiates s to (String) obj iff obj is in fact a String
    • May require a new CtInstanceOf interface that subtypes CtBinaryOperator to make sense

Preview features

  • Sealed types (preview 2, JEP 397)
    • Classes and interfaces can restrict how they can be subtyped with the sealed modifier
    • IMO not worth supporting until stable
jakobbraun commented

Can you give an estimation when java 16 support will be available? It would be really great to have this.

  • 👍2
slarse commented

Can you give an estimation when java 16 support will be available? It would be really great to have this.

@jakobbraun Support for type patterns is essentially done in #4020, we just hit a minor snag on finalizing. It should be available in the next beta release this weekend, I think.

The other big thing is records, and for that I can't really say. No one has yet taken it upon themselves to implement that, so I can't give an ETA on it.

raghav-deepsource commented

Note that sealed classes are slated to be stabilized in Java 17 (JEP-409)

monperrus commented

#4020 has added instanceof pattern matching, next step to close this issue is record support.

raghav-deepsource commented

I've created #4132 to discuss records.

  • 👍1
monperrus commented

Now that @MartinWitt's great #4134 is merged, it seems we can close this one.

WDYT?

MartinWitt commented

The last needed step is updating the GitHub page, then all is done.