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Google App Engine JDO Relationships

Schema : 1 user has 1 GeneralData and GeneralData cannot exist without user

@PersistenceCapable
public class User implements Serializable{

private static final long serialVersionUID = 1L;

@PrimaryKey
@Persistent
    private String key;

@Persistent(defaultFetchGroup = "true")
@Element(dependent = "true")
private GeneralData data;

public void setKey(String key) {
    this.key = key;
}

public String getKey() {
    return key;
}

pub开发者_如何学Golic void setData(GeneralData data) {
    this.data = data;
}

public GeneralData getData() {
    return data;
}
     }

    @PersistenceCapable
    public class GeneralData implements Serializable{
private static final long serialVersionUID = 1L;



@PrimaryKey
@Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
    private Long key;

@Persistent
private String name;

@Persistent(mappedBy = "data")
    private User user;

public void setName(String name) {
    this.name = name;
}

public String getName() {
    return name;
}

public void setKey(Long key) {
    this.key = key;
}

public Long getKey() {
    return key;
}


public void setUser(User user) {
    this.user = user;
}


public User getUser() {
    return user;
}

      }

I have 2 questions,Did I do correctly?

1) (Schema between User and GeneralData)

2) (To add instance to the google datastorage)


            PersistenceManager pm = PMF.get().getPersistenceManager();      
    User onUser = new User();
    GeneralData gd = new GeneralData();
    gd.setName(usrname);
    onUser.setKey(usrname);
    onUser.setData(gd);

    try {
        pm.makePersistent(onUser);
    } finally {
        pm.close();
    }
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