CrewMember.java

@Entity
public class CrewMember
{
    @Identifier(generator = IdentifierGenerator.SEQUENCE)
    @Attribute
    public long id;

    @Attribute
    public String firstName;

    @Attribute
    public String lastName;

    @Relationship(type = RelationshipType.MANY_TO_ONE,
            inverseClass = Sailboat.class,
            inverse = "crew",
            cascadePolicy = CascadePolicy.NONE)
    public Sailboat sailboat;

    // getters and setters
}