vaadin-maven-plugin failed to build-frontend after updating java level to 17

[kyberorg]

Description of the bug

After updating language version to Java 17 vaadin-maven-plugin fails to compile frontend due to reflection error.

[ERROR] Failed to execute goal com.vaadin:vaadin-maven-plugin:23.0.5:build-frontend (default) on project yalsee: Could not execute build-frontend goal: Error occured during goal execution: Cannot invoke "java.lang.Class.isInterface()" because the return value of "org.reflections.Reflections.forClass(String, java.lang.ClassLoader[])" is null

Full stacktrace is here

Expected behavior

Application compile into JAR-file without issues

Minimal reproducible example

• git clone https://github.com/kyberorg/yalsee.git
• cd yalsee
• git checkout 827-java-17-code-adaption
• mvn -Pproduction-mode,noTesting clean package

Versions

• Vaadin / Flow version: 23.0.5
• Java version: 17.0.3 OpenJDK
• OS version: "linux", version: "5.16.14-1-manjaro", arch: "amd64", family: "unix"
• Maven version: 3.8.1
• Browser version (if applicable): N/A
• Application Server (if applicable): N/A
• IDE (if applicable): IDEA

[mcollovati]

Seems like the problem is somehow related to lombok and --enable-preview flag.
The NPE is due to failure in loading class MyLinksPage

Preview features are not enabled for io/kyberorg/yalsee/ui/pages/mylinks/MyLinksPage (class file version 61.65535). Try running with '--enable-preview')

Adding the --enable-preview flag to the main process seems to solve the issue (eg export MAVEN_OPTS="$MAVEN_OPTS --enable-preview")

[kyberorg]

@mcollovati I can confirm, that adding --enable-preview leads to successful compilation. Thanks/Kiitos.

[jcaSteelElec]

Hi everyone, I am new on the github forum and I don't know where I can post my question about this issu.
Where I can add in my project "--enable-preview" ? in the POM ? Thnk you in advance

[ZhukovAlV]

https://stackoverflow.com/questions/72083752/enable-preview-features-in-an-early-access-version-of-java-in-intellij It is written in detail here