Java 14 - pattern matching and record

[lppedd]

Hi! This plugin should already support pattern matching, we just need to wait for a Gradle release which supports JDK 14 😄
Opened issue so it can be seen by others and closed when it's tested.

[bsideup]

Thanks for reporting! I will find time to check Java 14 (including records) next week and will report in this issue 👍

[lppedd]

@bsideup That's how they get compiled using JDK 14 😄

Pattern matching:

final Object v = "";

if (v instanceof String s) {
  System.out.println(s);
}

is compiled into

Object v = "";
String s;
if (v instanceof String && (s = (String)v) == (String)v) {
  System.out.println(s);
}

---

Record

public record Range(int lo, int hi) {
  public Range {
    if (lo > hi) {
	throw new IllegalArgumentException(String.format("%d, %d", lo, hi));
    }
  }
}

is compiled into

public final class Range extends java.lang.Record {
   private final int lo;
   private final int hi;

   public Range(int lo, int hi) { /* compiled code */ }

   public java.lang.String toString() { /* compiled code */ }

   public final int hashCode() { /* compiled code */ }

   public final boolean equals(java.lang.Object o) { /* compiled code */ }

   public int lo() { /* compiled code */ }

   public int hi() { /* compiled code */ }
}

[lppedd]

@bsideup it seems to use your plugin we'll have to wait the non-EA version of JDK 14.
Can't target class level 52 with enable-preview (to have access to records)

[bsideup]

@lppedd with Jabel, you don't need to enable preview features. Pattern matching is supported in master already, records will follow soon

[lppedd]

@bsideup I was testing with a clone of the project by enabling the RECORDS feature and using JDK 14. It seems that to have access to the Record base-class one must enable preview features.

[bsideup]

unlike other features, Records require some pre/post processing, so you can't just "enable" them.
I have a working prototype (see the screenshot here: https://twitter.com/bsideup/status/1233696266653249537 ), will submit a PR as soon as I feel confident about it.

[lppedd]

@bsideup oh that's good to know! Thanks a lot!

[bsideup]

See #16

[lppedd]

@bsideup thanks! Awesome work. 😁
Now I think a semi blocking issue is #9

[bsideup]

@lppedd you should not enable preview features with Jabel.

[lppedd]

@bsideup but if I don't enable them on Gradle build it will conflict with idea language settings

[bsideup]

@lppedd I just pushed a commit that explains how to configure IDEA & Gradle:
099fdb8

[lppedd]

@bsideup interesting! I'll give it a try, thanks!

[lppedd]

@bsideup works! Although it seems command line and IDEA have different behaviors.

Also see https://youtrack.jetbrains.com/issue/IDEA-235411