If there is a no-argument constructor marked as JsonCreator and a constructor reported as DefaultCreator, the DefaultCreator is incorrectly used.

[k163377]

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Describe the bug

If both JsonCreator and DefaultCreator are reported, the JsonCreator should take precedence.
On the other hand, in certain cases, the DefaultCreator may take precedence.

This issue is a Javaized version of the following
FasterXML/jackson-module-kotlin#932
#5040

Version Information

• 2.19.0-SNAPSHOT
• Probably the same for 2.18.3.

Reproduction

import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.cfg.MapperConfig;
import com.fasterxml.jackson.databind.introspect.AnnotatedClass;
import com.fasterxml.jackson.databind.introspect.NopAnnotationIntrospector;
import com.fasterxml.jackson.databind.introspect.PotentialCreator;
import com.fasterxml.jackson.databind.json.JsonMapper;
import org.junit.jupiter.api.Test;

import java.util.List;

public class Kotlin932Java {
    static class User {
        private final int age;

        public User(int age) { this.age = age; }

        @JsonCreator
        public User() { this(0); }

        public int getAge() { return age; }
    }

    static class AI extends NopAnnotationIntrospector {
        @Override
        public PotentialCreator findDefaultCreator(MapperConfig<?> config,
                                                   AnnotatedClass valueClass,
                                                   List<PotentialCreator> declaredConstructors,
                                                   List<PotentialCreator> declaredFactories) {
            if (valueClass.getRawType() != User.class) return null;

            return declaredConstructors.stream()
                    .filter(it -> it.paramCount() != 0)
                    .findFirst()
                    .orElse(null);
        }
    }

    @Test
    public void kotlin932() throws JsonProcessingException {
        ObjectMapper mapper = JsonMapper.builder().annotationIntrospector(new AI()).build();
        String json =
                "{\n" +
                "  \"age\": 25\n" +
                "}";

        User user = mapper.readValue(json, User.class);

        System.out.println(user);
    }
}

Expected behavior

Deserialization should succeed, but in fact has no property name ... is reported.

Additional context

The full stack trace when run on the 2.19 branch of kotlin-module.

com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Invalid type definition for type `com.fasterxml.jackson.module.kotlin.test.github.Kotlin932Java$User`: Argument #0 of Creator [constructor for `com.fasterxml.jackson.module.kotlin.test.github.Kotlin932Java$User` (1 arg), annotations: [null] has no property name (and is not Injectable): can not use as property-based Creator
 at [Source: REDACTED (`StreamReadFeature.INCLUDE_SOURCE_IN_LOCATION` disabled); line: 1, column: 1]

	at com.fasterxml.jackson.databind.exc.InvalidDefinitionException.from(InvalidDefinitionException.java:62)
	at com.fasterxml.jackson.databind.DeserializationContext.reportBadTypeDefinition(DeserializationContext.java:1893)
	at com.fasterxml.jackson.databind.deser.BasicDeserializerFactory._addSelectedPropertiesBasedCreator(BasicDeserializerFactory.java:535)
	at com.fasterxml.jackson.databind.deser.BasicDeserializerFactory._constructDefaultValueInstantiator(BasicDeserializerFactory.java:259)
	at com.fasterxml.jackson.databind.deser.BasicDeserializerFactory.findValueInstantiator(BasicDeserializerFactory.java:209)
	at com.fasterxml.jackson.databind.deser.BeanDeserializerFactory.buildBeanDeserializer(BeanDeserializerFactory.java:263)
	at com.fasterxml.jackson.databind.deser.BeanDeserializerFactory.createBeanDeserializer(BeanDeserializerFactory.java:152)
	at com.fasterxml.jackson.databind.deser.DeserializerCache._createDeserializer2(DeserializerCache.java:472)
	at com.fasterxml.jackson.databind.deser.DeserializerCache._createDeserializer(DeserializerCache.java:416)
	at com.fasterxml.jackson.databind.deser.DeserializerCache._createAndCache2(DeserializerCache.java:318)
	at com.fasterxml.jackson.databind.deser.DeserializerCache._createAndCacheValueDeserializer(DeserializerCache.java:285)
	at com.fasterxml.jackson.databind.deser.DeserializerCache.findValueDeserializer(DeserializerCache.java:175)
	at com.fasterxml.jackson.databind.DeserializationContext.findRootValueDeserializer(DeserializationContext.java:669)
	at com.fasterxml.jackson.databind.ObjectMapper._findRootDeserializer(ObjectMapper.java:5102)
	at com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:4972)
	at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:3887)
	at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:3855)
	at com.fasterxml.jackson.module.kotlin.test.github.Kotlin932Java.kotlin932(Kotlin932Java.java:50)
	at java.base/java.lang.reflect.Method.invoke(Method.java:569)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)

[cowtowncoder]

Ok. Looks like possible bug, although usage is bit odd -- if 0-args Constructor is expected to be used (I think?), how should age be passed?

Also, instead of

System.out.println(user);

it'd be better to assert (I know, there's now exception instead, but eventually this should work).

I think the problem probably has to do with special handling of "default" (0-args) construct (note: "findDefaultCreator()" is bad name, renamed in 3.0 as "findPreferredCreator".
It should be recognized, I suppose, as Properties-based one.
But unfortunately there is some specific code for use of default constructors.

ONe quick thing: does addition of mode = Mode.PROPERTIES on @JsonCreator help?

[k163377]

if 0-args Constructor is expected to be used

This is the state of affairs for minimum reproduction.
Originally, additional properties were registered from the setter after initialization with a 0-args constructor.

Also, instead of

Oops, I forgot to correct that.

mode = Mode.PROPERTIES on @JsonCreator help?

I tried all valid modes, but unfortunately they did not seem to work.