Interface validation is ran twice (Kotlin)

Hibernate Validator
1

Hello,

I am not sure if this is a Kotlin issue, but my problem can be reproduced by a simple test

interface Foo {
    @AssertTrue
    fun isValid() = false
}

class FooBean : Foo

class FooTest {

    @Test
    fun test() {

        val factory = Validation.buildDefaultValidatorFactory()
        val validator = factory.validator

        val errors = validator.validate(FooBean())

        assertThat(errors.size).isEqualTo(1)
    }
}

Expected :1
Actual :2

It seems that metadata that is created has property “valid” for both Foo and FooBean “declaring classes” so validation is run twice and resulting duplicate errors if not valid.

image
image.png1168×571 54.5 KB

See also https://paste.pics/44b73408ded6ebd46440fc80058a4e91

Kotlin decompiled

// Foo.java
package fi.foo;

import javax.validation.constraints.AssertTrue;
import kotlin.Metadata;

@Metadata(
   mv = {1, 1, 13},
   bv = {1, 0, 3},
   k = 1,
   d1 = {"\u0000\u0010\n\u0002\u0018\u0002\n\u0002\u0010\u0000\n\u0000\n\u0002\u0010\u000b\n\u0000\bf\u0018\u00002\u00020\u0001J\b\u0010\u0002\u001a\u00020\u0003H\u0017¨\u0006\u0004"},
   d2 = {"Lfi/foo/Foo;", "", "isValid", "", "foo"}
)
public interface Foo {
   @AssertTrue
   boolean isValid();

   @Metadata(
      mv = {1, 1, 13},
      bv = {1, 0, 3},
      k = 3
   )
   public static final class DefaultImpls {
      @AssertTrue
      public static boolean isValid(Foo $this) {
         return false;
      }
   }
}
// FooBean.java
package fi.foo;

import javax.validation.constraints.AssertTrue;
import kotlin.Metadata;

@Metadata(
   mv = {1, 1, 13},
   bv = {1, 0, 3},
   k = 1,
   d1 = {"\u0000\f\n\u0002\u0018\u0002\n\u0002\u0018\u0002\n\u0002\b\u0002\u0018\u00002\u00020\u0001B\u0005¢\u0006\u0002\u0010\u0002¨\u0006\u0003"},
   d2 = {"Lfi/foo/FooBean;", "Lfi/foo/Foo;", "()V", "foo"}
)
public final class FooBean implements Foo {
   @AssertTrue
   public boolean isValid() {
      return Foo.DefaultImpls.isValid(this);
   }
}

Any ideas?

EDIT: Using Kotlin @JvmDefault annotation for interface method fixes this issue, but it is not very nice workaround…