@MappedCollection => allow to configure table name?

[rdehuyss]

First of all, thanks again for this great project/product!

I have a suggestion to be able to reuse classes when using @MappedCollection. Currently, when using @MappedCollection for referencing sub-entities, a table name cannot be specified.

This results in classes that can not be reused as the table name needs to specified on the sub-entity. Due to the volume/amount of rows, I would like to have each @MappedCollection sub-entity in a separate table, per entity.

Problem description

Imagine the following Link class that I would like to reuse in different Spring Data JDBC Entities.

public class Link {

    private final String module;
    private final UUID id;

    public Link(String module, UUID id) {
        this.module = module;
        this.id = id;
    }

    public String getModule() {
        return module;
    }

    public UUID getId() {
        return id;
    }

    public String asString() {
        return module + ":" + id;
    }

    @Override
    public String toString() {
        return asString();
    }
}

The only way to embed this in multiple entities is by creating subclasses:

@Table(name = "task_links")
public class TaskLink extends Link {

    public TaskLink(String link) {
        super(link);
    }

    public TaskLink(String module, UUID id) {
        super(module, id);
    }
}

This way, it can be used using a @MappedCollection in the Task entity.

@Table(name = "tasks")
public class Task {

    @Id
    private final UUID id;

    @Version
    private final int version;

    @MappedCollection(idColumn = "task_id")
    private final List<TaskLink> taskLinks;

    ...
}

For another entity, the same approach is needed.

Proposed solution

Instead of the subclass, I would like to suggest the following approach, which would remove the need for the subclassing:

@Table(name = "tasks")
public class Task {

    @Id
    private final UUID id;

    @Version
    private final int version;

    @MappedCollection(idColumn = "task_id", tableName="task_links")
    private final List<Link> taskLinks;

    ...
}

Extra context

I also tried with a custom NamingStrategy but I do not have enough context when the getTableName is called as it does not provide any information whether this is called from a MappedCollection and if so, from which entity.