Remove warning generated on startup "Type [org.hibernate.type.CustomType@6142b9dd] defined no registration keys; ignoring"

[Bas83]

In our Spring Boot application (2.6.6), after updating Hibernate-Types-55 from 2.14.1 to 2.15.1 we are getting the following warning on startup:

Type [org.hibernate.type.CustomType@6142b9dd] defined no registration keys; ignoring

On the logger org.hibernate.type.BasicTypeRegistry

However, we're not creating any custom types, we're only using DecimalArrayType which indeed doesn't seem to have these registration keys.

We have this definition on 2 Entity classes:

@TypeDefs({
    @TypeDef(
        name = "big-decimal-array",
        typeClass = DecimalArrayType.class
    )
})

And then also a custom postgres dialect:

import com.vladmihalcea.hibernate.type.array.DecimalArrayType;
import java.sql.Types;
import org.hibernate.dialect.PostgreSQL95Dialect;

public class PostgreSQL95CustomDialect extends PostgreSQL95Dialect {

    public PostgreSQL95CustomDialect() {
        super();
        // this is not super extendible because now ALL arrays in custom queries are treated as BigDecimal arrays.
        this.registerHibernateType(Types.ARRAY, DecimalArrayType.class.getName());
    }
}

Are we doing anything wrong or is this an issue in the library?

[Bas83]

I just put a breakpoint on the line that actually throws the exception and it seems to be about the type com.vladmihalcea.hibernate.type.basic.NullableCharacterType

[vladmihalcea]

It could be the HibernateTypesContributors that auto-registers some Types, or it could be something else.

You can debug to see why this warning is generated and see whether the call originates in the HibernateTypesContributors. I will need as much context as possible so that I can understand why it's being generated.

[Bas83]

I just debugged, in the previous version this type com.vladmihalcea.hibernate.type.basic.NullableCharacterType was never registered in the BasicTypeRegistry, but now it is. Thus causing the warning there.

It is indeed being registered in the HibernateTypesContributors at the line typeContributions.contributeType(NullableCharacterType.INSTANCE, new String[0]);

(and then through MetadataBuildingProcess.contributeType at line 356)

[vladmihalcea]

Indeed, the issue can be replicated with the existing test cases, so I'll provide a fix for it when I have some time. In the meanwhile, you can simply ignore it as it won't affect the functionality of your application.

[vladmihalcea]

The solution requires the HibernateTypesContributor to provide the registration key.

So instead of:

typeContributions.contributeType(NullableCharacterType.INSTANCE);

it should use something like this:

typeContributions.contributeType(NullableCharacterType.INSTANCE, NullableCharacterType.INSTANCE.getName());

But, this is not just for the NullableCharacterType. All Types that implement UserType require this change.

[vladmihalcea]

Fixed.