Datanucleus 5.2.x 6.0.0-m1 JDO Enum usage, generated code not compiling

Question

I'm trying out ISIS in combination with JDO. I've stumbled upon an issue with Enums that I can reproduce on a direct/simple java JDO project.

The code can be gotten from

curl https://codeload.github.com/apache/isis-app-helloworld/zip/jdo | jar xv

I've added in the pom.xml the lombok dependency:

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.20</version>
        </dependency>

I create a class

package domainapp.modules.hello.dom.hwo;

import javax.jdo.annotations.IdentityType;

import lombok.AllArgsConstructor;
import lombok.Getter;

@javax.jdo.annotations.PersistenceCapable(identityType = IdentityType.DATASTORE, schema = "hello" )
@AllArgsConstructor
@Getter
public enum HelloWorldTypeEnum {
    BIG,
    SMALL;
}

and added in the HelloWorldObject the following member:

    @Getter @Setter
    @Extension(vendorName="datanucleus", key="enum-check-constraint", value="true")
    private HelloWorldTypeEnum type = HelloWorldTypeEnum.BIG;

The generated QHelloWorldObject does not compile:

...
    public QHelloWorldObject(PersistableExpression parent, String name, int depth)
    {
        super(parent, name);
        if (depth > 0)
        {
            this.type = new EnumExpressionImpl(this, "type", depth-1);
        }
        else
        {
            this.type = null;
        }
        this.name = new StringExpressionImpl(this, "name");
        this.notes = new StringExpressionImpl(this, "notes");
    }
...

The line

            this.type = new EnumExpressionImpl(this, "type", depth-1);

has the errors:

- The constructor EnumExpressionImpl(QHelloWorldObject, String, int) is undefined
- EnumExpressionImpl is a raw type. References to generic type EnumExpressionImpl<T> should be parameterized

I've created clean projects, stripping away all the ISIS stuff, and reducing it to only 2 java files, testing this with Datanucleus 5.2.8 and 6.0.0-m1 using OpenJDK 11. The result is always the same.

I'm on an Opensuse 15.2 machine with OpenJDK 11.

According to https://www.datanucleus.org/products/accessplatform/jdo/mapping.html Enums are supported.

Does anyone have a clue about what is going wrong?

Answer 1

It turned out to be as simple as this: don't make the enum Persistable.

Remove the line:

@javax.jdo.annotations.PersistenceCapable(identityType = IdentityType.DATASTORE, schema = "hello" )

from the enum definition.