quarkus: REST Reactive Client: PartFilename annotation doesn't work if member is anything else than java.io.File

Describe the bug

I have tested the new @PartFilename annotation in the REST Reactive client (Quarkus 2.7.0.CR1). See issue #22658 However, the annotation seems to work only if the respective annotated member is of type java.io.File. I tested with java.nio.Buffer and java.lang.String. If one of these two types is used, the file name is not transferred.

Works as expected:

public class OurForm {
  @FormParam("files")
  @PartFilename("document.txt")
  @PartType(MediaType.TEXT_PLAIN)
  private File documentFile;
}

Doesn’t work:

public class OurForm {
  @FormParam("files")
  @PartFilename("document.txt")
  @PartType(MediaType.TEXT_PLAIN)
  private String documentFile;
}

public class OurForm {
  @FormParam("files")
  @PartFilename("document.txt")
  @PartType(MediaType.TEXT_PLAIN)
  private Buffer documentFile;
}

Expected behavior

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Actual behavior

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How to Reproduce?

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Output of uname -a or ver

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Output of java -version

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GraalVM version (if different from Java)

2.7.0.CR1

Quarkus version or git rev

No response

Build tool (ie. output of mvnw --version or gradlew --version)

No response

Additional information

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