Datanucleus mongodb引用

Question

我可以通過DBRef獲取字段嗎？ 我不得不單獨收集映射到：

@PersistenceCapable(table = "group") 
public class MyGroup 
{ 
    @PrimaryKey 
    @Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY, column = "_id") 
    private String id; 
    private String name; 
    private Person person; 

    // getters/setters 
    ... 
} 

@PersistenceCapable(table = "people") 
public class Person 
{ 
    @PrimaryKey 
    @Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY, column = "_id") 
    private String id; 
    private String firstName; 
    private String lastName; 

    // getters/setters 
    ... 
} 

我想獲得個人域名（目前我個人爲空）：

MyGroup myGroup = persistenceManager.getObjectById(MyGroup.class, "5230a918ac8c95fd3d9a3dfa") 
myGroup.getPerson().getFirstName(); 

和執行查詢：

Query query = persistenceManager.newQuery(MyGroup.class); 
query.setFilter("persone.firstName == \"Tester\""); 

Answer 1

DataNucleus不支持MongoDB數據存儲上的DBRef： http://www.datanucleus.org/servlet/forum/viewthread_thread,7924#38188