At least one attribute with a value appears to be required

[brucent]

I wanted to create an object that just keeps a one-to-many association, so I created model classes like these (getters and setters removed):

@Model
public class Student {
    @Id
    private Long id;

    @CollectionSet(of = Pen.class)
    @Indexed
    private Set<Pen> pens;

    //It appears that at least one attribute class is required
    //@Attribute
    //private String name;
}


@Model
public class Pen {
    @Id
    private Long id;

    @Attribute
    private String color;
}

Using these classes generated an error with JOhm 0.5.0 when you add a Pen to the Student's collection. I was able to work around the problem if I added an attribute to Student and gave it a value.

public class JOhmTest {

    public JOhmTest() {
    }

    @Before
    public void setup() throws Exception {
        JedisPool jedisPool = new JedisPool(new GenericObjectPool.Config(), "localhost");
        JOhm.setPool(jedisPool);
    }

    /**
     * Test of main method, of class JOhmTest.
     */
    @Test
    public void testMain() {
        System.out.println("main");

        Pen pen1 = new Pen();
        pen1.setColor("blue");
        JOhm.save(pen1);

        Student student = new Student();
        //student.setName("joe");
        JOhm.save(student);

        Pen pen2 = new Pen();
        pen2.setColor("black");
        JOhm.save(pen2);

        student.getPens().add(pen1);
        student.getPens().add(pen2);

        int id = (int) student.getId().intValue();
        Student foundStudent = JOhm.get(Student.class, id);
        System.out.println(foundStudent);

        assertEquals(2, foundStudent.getPens().size());
    }
}