休眠一對多雙向關聯，不使用Spring Data加載

Question

我有一個雙向映射如下

@Entity
@Table(name = "Stock")
public class StockEntity implements Serializable {


    private String planNum;

    private Set<StockOptionEntity> options = new HashSet<StockOptionEntity>(0);



    @OneToMany(fetch = FetchType.EAGER, mappedBy="stock")
    public Set<StockOptionEntity> getOptions() {
        return Options;
    }

    public void setOptions(Set<StockOptionEntity> Options) {
        this.Options = Options;
    }
}

然后我有另一個映射如下。

@Entity
@Table(name = "StockOption")
@IdClass(StockOptionEntityPK.class)
public class StockOptionEntity implements Serializable {



    private StockEntity stock;

    @ManyToOne(cascade = CascadeType.ALL)
    @JoinColumn(name = "PlanNum", insertable = false, updatable = false)    
    public StockEntity getStock() {
        return Stock;
    }

    public void setStock(StockEntity Stock) {
        this.Stock = Stock;
    }
}

然后，我將Session，Entity和Transaction Manager的Spring Bean聲明如下

@Bean
public DataSource msSqlDataSource() {
    SQLServerConnectionPoolDataSource dataSource = new SQLServerConnectionPoolDataSource();
    ...........
    return dataSource;

}
@Bean
@DependsOn({ "msSqlDataSource"})    
public LocalSessionFactoryBean sessionFactory() {
    LocalSessionFactoryBean sessionFactory = new LocalSessionFactoryBean();
    try {
        sessionFactory.setDataSource(msSqlDataSource());
    } catch (Exception e) {
        log.error("Failed to attach dataSource object to SessionFactory bean. "
                + "Exception: " + e.getMessage());
    }
    sessionFactory
            .setPackagesToScan("com.firstx.db.entity.*");
    sessionFactory.setHibernateProperties(hibernateProperties());

    return sessionFactory;
}
@Bean
@DependsOn({ "sessionFactory","msSqlDataSource"})
public EntityManagerFactory entityManagerFactory() {

    HibernateJpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
    vendorAdapter.setGenerateDdl(true);

    LocalContainerEntityManagerFactoryBean factory = new LocalContainerEntityManagerFactoryBean();
    factory.setJpaVendorAdapter(vendorAdapter);
    factory.setPackagesToScan("com.firstx.db.entity.*");
    try {
        factory.setDataSource(msSqlDataSource());
    } catch (Exception e) {
        log.error("Failed to attach dataSource object to EntityManagerFactor bean. "
                + "Exception: " + e.getMessage());
    }
    factory.afterPropertiesSet();

    return factory.getObject();
}
  @Bean
   public PlatformTransactionManager transactionManager(){
      JpaTransactionManager transactionManager = new JpaTransactionManager();
      transactionManager.setEntityManagerFactory(
              entityManagerFactory() );
      return transactionManager;
   }

最后，我使用Spring數據存儲庫-repository.findOne（...）方法與StockOptions一起提取我的Stock對象。

在這種情況下，即時通訊無法檢索股票期權的集合。 集合為空。

我嘗試了以下方法（將Spring Bean保持不變），

1. 將關系轉換為單向關系（通過刪除mapledBy和相關的東西）。
2. 刪除了Set的初始化。
3. 刪除了StockOption的ID類

以上兩個選項均無效。

在調試中，我看到StockOptions已成功檢索並加載到會話緩存中。 但是，我無法弄清楚為什么它實際上沒有被加載回父對象。

下面是調試...

1853270 [http-nio-8080-exec-10] TRACE o.h.e.i.DefaultInitializeCollectionEventListener - Initializing collection [com.firstx.db.entity.base.StockEntity.options#d97]
1853270 [http-nio-8080-exec-10] TRACE o.h.e.i.DefaultInitializeCollectionEventListener - Checking second-level cache
1853270 [http-nio-8080-exec-10] TRACE o.h.e.i.DefaultInitializeCollectionEventListener - Collection not cached
1853271 [http-nio-8080-exec-10] DEBUG o.h.l.c.p.AbstractLoadPlanBasedCollectionInitializer - Loading collection: [com.firstx.db.entity.base.StockEntity.options#d97]
1853271 [http-nio-8080-exec-10] DEBUG org.hibernate.SQL - select options0_.PlanNum as PlanNum1_11_0_, options0_.PlanNum as PlanNum1_13_0_, options0_.OptionCode as Optio2_13_0_, options0_.PlanNum as PlanNum1_13_1_ ......... from StockOption options0_ where options0_.PlanNum=?
1853271 [http-nio-8080-exec-10] TRACE o.h.e.j.i.JdbcCoordinatorImpl - Registering statement [SQLServerPreparedStatement:13]
1853271 [http-nio-8080-exec-10] TRACE o.h.e.j.i.JdbcCoordinatorImpl - Registering last query statement [SQLServerPreparedStatement:13]
1853271 [http-nio-8080-exec-10] TRACE o.h.type.descriptor.sql.BasicBinder - binding parameter [1] as [VARCHAR] - [d97]
1853271 [http-nio-8080-exec-10] TRACE o.h.l.p.e.i.AbstractLoadPlanBasedLoader - Bound [2] parameters total
1853305 [http-nio-8080-exec-10] TRACE o.h.e.j.i.JdbcCoordinatorImpl - Registering result set [SQLServerResultSet:68]
1854044 [http-nio-8080-exec-10] DEBUG o.h.l.p.e.p.i.ResultSetProcessorImpl - Preparing collection intializer : [com.firstx.db.entity.base.StockEntity.options#d97]
1854044 [http-nio-8080-exec-10] TRACE o.h.e.loading.internal.LoadContexts - Constructing collection load context for result set [SQLServerResultSet:68]
1854773 [http-nio-8080-exec-10] TRACE o.h.e.l.i.CollectionLoadContext - Starting attempt to find loading collection [[com.firstx.db.entity.base.StockEntity.options#d97]]
1854773 [http-nio-8080-exec-10] TRACE o.h.e.loading.internal.LoadContexts - Attempting to locate loading collection entry [CollectionKey[com.firstx.db.entity.base.StockEntity.options#d97]] in any result-set context
1854774 [http-nio-8080-exec-10] TRACE o.h.e.loading.internal.LoadContexts - Collection [CollectionKey[com.firstx.db.entity.base.StockEntity.options#d97]] not located in load context
1854774 [http-nio-8080-exec-10] TRACE o.h.e.l.i.CollectionLoadContext - Collection not yet initialized; initializing
1854774 [http-nio-8080-exec-10] TRACE o.h.l.p.e.p.i.ResultSetProcessorImpl - Processing result set
1854774 [http-nio-8080-exec-10] DEBUG o.h.l.p.e.p.i.ResultSetProcessorImpl - Starting ResultSet row #0
1854774 [http-nio-8080-exec-10] TRACE o.h.t.descriptor.sql.BasicExtractor - extracted value ([PlanNum1_13_1_] : [VARCHAR]) - [D97]
1854774 [http-nio-8080-exec-10] TRACE o.h.t.descriptor.sql.BasicExtractor - extracted value ([Optio2_13_1_] : [VARCHAR]) - [03]
1854775 [http-nio-8080-exec-10] TRACE o.h.t.descriptor.sql.BasicExtractor - extracted value ([PlanNum1_11_0_] : [VARCHAR]) - [D97]
1854775 [http-nio-8080-exec-10] DEBUG o.h.l.p.e.p.i.CollectionReferenceInitializerImpl - Found row of collection: [com.firstx.db.entity.base.StockEntity.options#D97]
1855453 [http-nio-8080-exec-10] TRACE o.h.e.l.i.CollectionLoadContext - Starting attempt to find loading collection [[com.firstx.db.entity.base.StockEntity.options#D97]]
1855454 [http-nio-8080-exec-10] TRACE o.h.e.loading.internal.LoadContexts - Attempting to locate loading collection entry [CollectionKey[com.firstx.db.entity.base.StockEntity.options#D97]] in any result-set context
1855454 [http-nio-8080-exec-10] TRACE o.h.e.loading.internal.LoadContexts - Collection [CollectionKey[com.firstx.db.entity.base.StockEntity.options#D97]] not located in load context
1855454 [http-nio-8080-exec-10] TRACE o.h.e.l.i.CollectionLoadContext - Collection already initialized; ignoring
1856195 [http-nio-8080-exec-10] DEBUG o.h.l.p.e.p.i.ResultSetProcessorImpl - Starting ResultSet row #1
1856196 [http-nio-8080-exec-10] TRACE o.h.t.descriptor.sql.BasicExtractor - extracted value ([PlanNum1_13_1_] : [VARCHAR]) - [D97]
1856196 [http-nio-8080-exec-10] TRACE o.h.t.descriptor.sql.BasicExtractor - extracted value ([Optio2_13_1_] : [VARCHAR]) - [18]
1856196 [http-nio-8080-exec-10] TRACE o.h.t.descriptor.sql.BasicExtractor - extracted value ([PlanNum1_11_0_] : [VARCHAR]) - [D97]
1856196 [http-nio-8080-exec-10] DEBUG o.h.l.p.e.p.i.CollectionReferenceInitializerImpl - Found row of collection: [com.firstx.db.entity.base.StockEntity.options#D97]
1856819 [http-nio-8080-exec-10] TRACE o.h.e.l.i.CollectionLoadContext - Starting attempt to find loading collection [[com.firstx.db.entity.base.StockEntity.options#D97]]
1856820 [http-nio-8080-exec-10] TRACE o.h.e.loading.internal.LoadContexts - Attempting to locate loading collection entry [CollectionKey[com.firstx.db.entity.base.StockEntity.options#D97]] in any result-set context
1856820 [http-nio-8080-exec-10] TRACE o.h.e.loading.internal.LoadContexts - Collection [CollectionKey[com.firstx.db.entity.base.StockEntity.options#D97]] not located in load context
1856820 [http-nio-8080-exec-10] TRACE o.h.e.l.i.CollectionLoadContext - Collection already initialized; ignoring
1857454 [http-nio-8080-exec-10] DEBUG o.h.l.p.e.p.i.ResultSetProcessorImpl - Starting ResultSet row #2
1857454 [http-nio-8080-exec-10] TRACE o.h.t.descriptor.sql.BasicExtractor - extracted value ([PlanNum1_13_1_] : [VARCHAR]) - [D97]
1857454 [http-nio-8080-exec-10] TRACE o.h.t.descriptor.sql.BasicExtractor - extracted value ([Optio2_13_1_] : [VARCHAR]) - [42]
1857455 [http-nio-8080-exec-10] TRACE o.h.t.descriptor.sql.BasicExtractor - extracted value ([PlanNum1_11_0_] : [VARCHAR]) - [D97]
1857455 [http-nio-8080-exec-10] DEBUG o.h.l.p.e.p.i.CollectionReferenceInitializerImpl - Found row of collection: [com.firstx.db.entity.base.StockEntity.options#D97]
1858028 [http-nio-8080-exec-10] TRACE o.h.e.l.i.CollectionLoadContext - Starting attempt to find loading collection [[com.firstx.db.entity.base.StockEntity.options#D97]]
1858028 [http-nio-8080-exec-10] TRACE o.h.e.loading.internal.LoadContexts - Attempting to locate loading collection entry [CollectionKey[com.firstx.db.entity.base.StockEntity.options#D97]] in any result-set context
1858028 [http-nio-8080-exec-10] TRACE o.h.e.loading.internal.LoadContexts - Collection [CollectionKey[com.firstx.db.entity.base.StockEntity.options#D97]] not located in load context
1858028 [http-nio-8080-exec-10] TRACE o.h.e.l.i.CollectionLoadContext - Collection already initialized; ignoring
1858628 [http-nio-8080-exec-10] TRACE o.h.l.p.e.p.i.ResultSetProcessorImpl - Done processing result set (3 rows)
1858628 [http-nio-8080-exec-10] TRACE o.h.l.p.e.p.i.AbstractRowReader - Total objects hydrated: 0
1859193 [http-nio-8080-exec-10] TRACE o.h.e.loading.internal.LoadContexts - Attempting to locate loading collection entry [CollectionKey[com.firstx.db.entity.base.StockEntity.options#d97]] in any result-set context
1859193 [http-nio-8080-exec-10] TRACE o.h.e.loading.internal.LoadContexts - Collection [CollectionKey[com.firstx.db.entity.base.StockEntity.options#d97]] located in load context
1861703 [http-nio-8080-exec-10] TRACE o.h.e.l.i.CollectionLoadContext - Removing collection load entry [org.hibernate.engine.loading.internal.LoadingCollectionEntry<rs=SQLServerResultSet:68, coll=[com.firstx.db.entity.base.StockEntity.options#d97]>@8edfd0]
1863159 [http-nio-8080-exec-10] DEBUG o.h.e.l.i.CollectionLoadContext - 1 collections were found in result set for role: com.firstx.db.entity.base.StockEntity.options
1863159 [http-nio-8080-exec-10] TRACE o.h.e.l.i.CollectionLoadContext - Ending loading collection [org.hibernate.engine.loading.internal.LoadingCollectionEntry<rs=SQLServerResultSet:68, coll=[com.firstx.db.entity.base.StockEntity.options#d97]>@8edfd0]
1864512 [http-nio-8080-exec-10] DEBUG o.h.e.l.i.CollectionLoadContext - Collection fully initialized: [com.firstx.db.entity.base.StockEntity.options#d97]
1865190 [http-nio-8080-exec-10] DEBUG o.h.e.l.i.CollectionLoadContext - 1 collections initialized for role: com.firstx.db.entity.base.StockEntity.options
1865190 [http-nio-8080-exec-10] TRACE o.h.e.j.i.JdbcCoordinatorImpl - Releasing result set [SQLServerResultSet:68]
1865190 [http-nio-8080-exec-10] TRACE o.h.e.j.i.JdbcCoordinatorImpl - Closing result set [SQLServerResultSet:68]
1865190 [http-nio-8080-exec-10] TRACE o.h.e.j.i.JdbcCoordinatorImpl - Releasing statement [SQLServerPreparedStatement:13]
1865190 [http-nio-8080-exec-10] TRACE o.h.e.j.i.JdbcCoordinatorImpl - Closing prepared statement [SQLServerPreparedStatement:13]
1865211 [http-nio-8080-exec-10] TRACE o.h.e.j.i.JdbcCoordinatorImpl - Starting after statement execution processing [ON_CLOSE]
1865979 [http-nio-8080-exec-10] DEBUG o.h.l.c.p.AbstractLoadPlanBasedCollectionInitializer - Done loading collection
1865979 [http-nio-8080-exec-10] TRACE o.h.e.i.DefaultInitializeCollectionEventListener - Collection initialized
1866720 [http-nio-8080-exec-10] DEBUG o.h.l.e.p.AbstractLoadPlanBasedEntityLoader - Done entity load : com.firstx.db.entity.base.StockEntity#d97
1866720 [http-nio-8080-exec-10] TRACE org.hibernate.internal.SessionImpl - Setting cache mode to: NORMAL
1866720 [http-nio-8080-exec-10] DEBUG o.h.e.t.spi.AbstractTransactionImpl - committing
1866720 [http-nio-8080-exec-10] TRACE org.hibernate.internal.SessionImpl - before transaction completion
1866740 [http-nio-8080-exec-10] DEBUG o.h.e.t.i.jdbc.JdbcTransaction - committed JDBC Connection
1866740 [http-nio-8080-exec-10] DEBUG o.h.e.t.i.jdbc.JdbcTransaction - re-enabling autocommit
1866763 [http-nio-8080-exec-10] TRACE o.h.e.t.i.TransactionCoordinatorImpl - after transaction completion
1866763 [http-nio-8080-exec-10] TRACE org.hibernate.internal.SessionImpl - after transaction completion
1866763 [http-nio-8080-exec-10] TRACE org.hibernate.internal.SessionImpl - Setting flush mode to: AUTO
1866763 [http-nio-8080-exec-10] TRACE org.hibernate.internal.SessionImpl - Closing session
1866764 [http-nio-8080-exec-10] TRACE o.h.e.j.i.JdbcCoordinatorImpl - Closing JDBC container [org.hibernate.engine.jdbc.internal.JdbcCoordinatorImpl@6dc5a3df]
1866764 [http-nio-8080-exec-10] TRACE o.h.e.j.i.LogicalConnectionImpl - Closing logical connection
1866764 [http-nio-8080-exec-10] DEBUG o.h.e.j.i.LogicalConnectionImpl - Releasing JDBC connection
1866764 [http-nio-8080-exec-10] DEBUG o.h.e.j.i.LogicalConnectionImpl - Released JDBC connection

另外，我沒有啟用任何緩存選項。

如您在上面所看到的，正在提取stockoption集合，但是沒有將其插入到stock對象中。

---

更新

在我最初的帖子中，大寫的股票和期權是一個發現並替換錯誤。

我寫了一個簡單的類，繞過spring數據，結果是它起作用了！ 該實體已加載，沒有任何問題。

我認為即時通訊在Spring數據配置上做錯了（可能是）。 但不確定。

以下是適用於相同映射的簡單（常規休眠DAO樣式）：

@Repository
public class NewStock {

    @Autowired
    private SessionFactory  sessionFactory;

    public SessionFactory getSessionFactory() {
        return sessionFactory;
    }

    public void setSessionFactory(SessionFactory sessionFactory) {
        this.sessionFactory = sessionFactory;
    }

    public StockEntity retrieveStock(String planNum) {

        Session session = sessionFactory.openSession();
        session.beginTransaction();
        List<StockEntity> stockList = session
                                .createQuery("from StockEntity where planNum = '" +
                                        planNum+ "'")
                                        .list();
        session.close();


        return stockList.get(0);

    }

}

---

請幫助找出根本原因。

Answer 1

請嘗試更改

 private StockEntity Stock;

進入

private StockEntity stock;

Answer 2

聲明字段以及相應的getter和setter方法時，必須遵循Java Bean命名約定 。

在StockEntity.java類中，屬性Options應該是options ，它應該以小寫字母開頭。

同樣適用於您的其他實體StockOptionEntity.java類，屬性Stock應該是stock 。

現在出現問題了，根據日志，它顯示以下消息：

1854774 [http-nio-8080-exec-10] TRACE o.h.e.loading.internal.LoadContexts - 
Collection [CollectionKey[com.firstx.db.entity.base.StockEntity.options#d97]] not 
located in load context

此消息表明，休眠狀態無法在StockEntity類中找到名為options的屬性。 因此，即使休眠狀態獲得了StockOptionEntity的記錄，因為它沒有找到該屬性，它也忽略了它。

要解決此問題，只需遵循Java bean命名約定。