HarmonyOS鸿蒙Next中ORM数据库初始化显示找不到类UserHelper类

HarmonyOS鸿蒙Next中ORM数据库初始化显示找不到类UserHelper类

报错为：

C:\Users\huawei\DevEcoStudioProjects\test3\entry\build\generated\source\annotation\debug\com\example\test\slice\UserHelper.java:28: 错误: 找不到符号

```java
public static MainAbilitySlice.UserHelper getInstance() {
    DatabaseHelper helper = new DatabaseHelper(this.getContext());
    OrmContext context = helper.getOrmContext("BookStore", "BookStore.db", BookStore.class);
    this.getDatabaseDir();
    User user = new User();
    user.setUserId(0);
    user.setFirstName("Zhang");
    user.setLastName("San");
    user.setAge(29);
    user.setBalance(100.51);
    boolean isSuccessed = context.insert(user);
    isSuccessed = context.flush();
    OrmPredicates query = context.where(User.class).equalTo("lastName", "San");
    List<User> users = context.query(query);
}

[@Database](/user/Database)(entities = {User.class, Book.class}, version = 1)
public abstract static class BookStore extends OrmDatabase {
}

[@Entity](/user/Entity)(tableName = "user", ignoredColumns = {"ignoreColumn1", "ignoreColumn2"},
        indices = {@Index(value = {"firstName", "lastName"}, name = "name_index", unique = true)})
public static class User extends OrmObject {
    
    @PrimaryKey(autoGenerate = true)
    private Integer userId;
    private String firstName;
    private String lastName;
    private int age;
    private double balance;
    private int ignoreColumn1;
    private int ignoreColumn2;
}