如何使用datanucleus-appengine 2.0.0-final的JDOQL查询应用获取组

时间:2012-02-21 23:27:33

标签: google-app-engine jdo fetch datanucleus jdoql

升级到2.0版最终版本的datanucleus-appengine后,在通过查询API使用JDOQL查询时,现在似乎忽略了获取组。我不确定它是否是库中的错误或我做错了。

我定义了一个'User'实体,其中包含对其他实体的多个1:M List引用。我们通过提取组来控制这些引用的获取,例如:

@PersistenceCapable(identityType = IdentityType.APPLICATION, detachable="true")
@FetchGroups({@FetchGroup(name="bits",
                       members=@Persistent(name="userHistory"),
@Persistent(name="userBranding")}),
             @FetchGroup(name="content", members={@Persistent(name="userContent")})})

public class User implements Serializable {

    @PrimaryKey
    @Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
    private String username;

    @Persistent
    private String email;

    @Persistent(mappedBy = "contentUser", defaultFetchGroup = "false")
    @Element(dependent = "true")
    @Order(extensions = @Extension(vendorName = "datanucleus", key = "list-ordering",value="contentKey asc"))
    private List<Content> userContent;

    @Persistent(mappedBy = "historyUser", defaultFetchGroup = "false")
    @Element(dependent = "true")
    @Order(extensions = @Extension(vendorName = "datanucleus", key = "list-ordering", value = "createdDate asc"))
    private List<History> userHistory;

    @Persistent(mappedBy = "brandingUser", defaultFetchGroup = "false")
    @Element(dependent = "true")
    private List<MediaBranding> userBranding;
...
}

根据上述定义,我的理解是:

  • 仅使用默认提取组时,不会获取任何关系。
  • 如果指定了'bits'获取组,则应该获取userHistory和userBranding。
  • 如果指定了'content'获取组,则应该获取userContent。

使用JDOQL通过电子邮件字段获取用户时,无论指定哪个获取组,都不会获取任何关系。如果我使用getById()来获取用户,则会按预期应用提取组。

我已关闭L2缓存(在jdoquery.xml中设置为NONE)。

我用来获取的测试用例如下所示(使用版本2.0.0-final失败,通过版本1.0.10)。

@SuppressWarnings("unchecked")
    @Test
    public void testAddRetrieveUserByJDOQLQueryFetchGroups() {
        PersistenceManager pm;
        User u = persistUserAndFriends();

        pm = getPMF().getPersistenceManager();

        User result = null;
        try {
            pm.getFetchPlan().addGroup("bits");
            pm.getFetchPlan().addGroup("content");
            log.info("Groups in fetch plan: " + pm.getFetchPlan().getGroups());
            Query query = pm.newQuery(User.class);           
            query.setFilter("email == emailParam");
            query.declareParameters("java.lang.String emailParam");
            List<User> results = (List<User>) query.execute("hello@site.net");
            assertEquals(1, results.size());
            result = results.get(0);
            pm.makeTransient(result, true);
        } finally {
            pm.close();
        }
        assertNotNull("User history should be fetched", result.getUserHistory());
        assertNotNull("User branding should be fetched", result.getUserBranding());
        assertEquals("Should be two history children", 2, result.getUserHistory().size());
        assertEquals("Should be two branding children", 2, result.getUserBranding().size());
        assertEquals("Should be a content child", 1, result.getUserContent().size());
    }

我是以错误的方式解决这个问题吗?

0 个答案:

没有答案