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我在我的项目中使用 Java8、Hibernate 5.2.10Final 和 MySQL 5.7。但是我在使用时遇到了一些问题java.time.LocalDate。有两个实体类：

TradeDay.class:

@Entity
@Table(name = "ENTITY__TRADE_DAY")
public class TradeDay {
    @Id
    @Column(name = "TRADE_DAY_DATE")
    private LocalDate date;

    ........

    @OneToMany(targetEntity = Transaction.class, mappedBy = "tradeDay", cascade = CascadeType.ALL)
    @LazyCollection(LazyCollectionOption.EXTRA)
    private Set<Transaction> transactionSet=new LinkedHashSet<>();

    ........
}

和 Transaction.class

@Entity
@Table(name = "ENTITY__TRANSACTION")
public class Transaction {
    @Id
    @GeneratedValue(strategy = GenerationType.TABLE, generator = "increase")
    @TableGenerator(name = "increase", allocationSize = 1)
    @Column(name = "TRANSACTION_INDEX")
    private int index;

    ........

    @ManyToOne(targetEntity = TradeDay.class,fetch = FetchType.LAZY)
    @JoinColumn(name = "TRADE_DAY_DATE")
    private TradeDay tradeDay;

    ........
}

然后我遇到的问题：

1.当我LocalDate在HQL中用作key时，SQL中的最终值将是上一个日期。例如：

@Override
public List<Transaction> getTransactionList(LocalDate date) {
    Session session = HibernateSessionManager.getCurrentSession();
    Query<Transaction> query = session.createQuery("from Transaction t where t.date=? order by t.index asc", Transaction.class);
    query.setParameter(0,date);
    return query.list();
}

ps：t.date等于transaction.getTradeDay().getDate()。

我使用此代码在数据库中搜索。但是，当我给出一个参数时2010-12-18，结果的日期都是2010-12-17.

2.我@LazyCollection(LazyCollectionOption.EXTRA)用来确保当我调用方法transactionSet.size()休眠时只会执行一个“计数”SQL。它确实有效，但是当我迭代它时，集合中什么都没有。

测试代码：

......//Before, get a TradeDay entity

Set<Transaction> transactionSet=tradeDay.getTransactionSet();
System.out.println(tradeDay.getDate()+" complete with "+transactionSet.size()+" records.");
for(Transaction transaction:transactionSet){
    System.out.println(transaction.getIndex());
}

//Impl of `getTransactionList` is the code above
List<Transaction> transactionList=DAOManager.getTransactionDAO().getTransactionList(tradeDay.getDate());
System.out.println(tradeDay.getDate()+" complete with "+transactionList.size()+" records.");
for(Transaction transaction:transactionList){
    System.out.println(transaction.getIndex());
}

输出如下：

//Just a count SQL because of @LazyCollection(LazyCollectionOption.EXTRA)
Hibernate: select count(TRANSACTION_INDEX) from ENTITY__TRANSACTION where TRADE_DAY_DATE =?

//count SQL got 4 result
1990-12-20 complete with 4 records.

//Iterate set, real SQL
Hibernate: select ...... from ENTITY__TRANSACTION transactio0_ where transactio0_.TRADE_DAY_DATE=?

//No index output???

//SQL by getTransactionList
Hibernate: select ...... from ENTITY__TRANSACTION transactio0_ where transactio0_.TRANSACTION_DATE=? order by transactio0_.TRANSACTION_INDEX asc

//Got 4 result too
1990-12-20 complete with 4 records.

//Success print the index
5535748
5882738
5925376
6165413

我该如何解决这些问题？谢谢你的帮助。

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