Question

我在查询我的Google数据存储区实例时遇到了NucleusUserException。我正在查询扩展它的类MappedSuperclass上存在的字段。这是我的抽象类，包含我感兴趣的字段：

@Entity
@MappedSuperclass
@JsonIgnoreProperties({ "password" })
public abstract class AbstractUser implements User {
  @Persistent
  protected String emailAddress;

  public void setEmailAddress(String email) {
     this.emailAddress = email;
  }

  public String getEmailAddress() {
    return this.emailAddress;
  }

  @Id
  @GeneratedValue(strategy = GenerationType.IDENTITY)
  private Long key;

  //Other stuff.
}

具体实例如下所示：

@Entity
public class Client extends AbstractUser {
//Things that only clients have.
}

我失败的查询如下所示：

List existingUsersWithEmail = manager
                              .createQuery(
                             "SELECT c from Client AS c WHERE c.emailaddress = :mail")
                             .setParameter("mail", request.getEmailAddress())
                             .getResultList();

例外是：

Cannot access field emailaddress on type org.workouthound.user.Client
org.datanucleus.exceptions.NucleusUserException: Cannot access field emailaddress on type org.workouthound.user.Client
at org.datanucleus.query.compiler.JavaQueryCompiler.getType(JavaQueryCompiler.java:552)
at org.datanucleus.query.compiler.JavaQueryCompiler.getType(JavaQueryCompiler.java:529)
at org.datanucleus.query.symbol.SymbolTable.getType(SymbolTable.java:118)
at org.datanucleus.query.expression.PrimaryExpression.bind(PrimaryExpression.java:118)
at org.datanucleus.query.expression.DyadicExpression.bind(DyadicExpression.java:85)
at org.datanucleus.query.compiler.JavaQueryCompiler.compileFilter(JavaQueryCompiler.java:299)
at org.datanucleus.query.compiler.JPQLCompiler.compile(JPQLCompiler.java:75)
at org.datanucleus.store.query.AbstractJPQLQuery.compileInternal(AbstractJPQLQuery.java:246)
at org.datanucleus.store.query.Query.setImplicitParameter(Query.java:690)
at org.datanucleus.jpa.JPAQuery.setParameter(JPAQuery.java:428)
at org.workouthound.rest.client.UserResources.emailIsRegistered(UserResources.java:55)
at org.workouthound.rest.client.UserResources.createClient(UserResources.java:33)

我是DataNucleus和Google Data Store的新手。我试图按照here概述的教程，但我很可能错过了一些东西。请告诉我，因为有必要提供更多信息。

更新
如果我将字段名称更改为email以及getter，setter和query，它的工作原理......为什么？

NucleusUserException：无法访问实体扩展映射的超类的字段

0 个答案: