休眠和货币精确度

Question

我有一个hibernate映射如下:

<hibernate-mapping>
    <class name="kochman.elie.data.types.InvoiceTVO" table="INVOICE">
        <id name="id" column="ID">
            <generator class="increment"/>
        </id>
        <property name="date" column="INVOICE_DATE"/>
        <property name="customerId" column="CUSTOMER_ID"/>
        <property name="schoolId" column="SCHOOL_ID"/>
        <property name="bookFee" column="BOOK_FEE"/>
        <property name="adminFee" column="ADMIN_FEE"/>
        <property name="totalFee" column="TOTAL_FEE"/>
    </class>
</hibernate-mapping>    

其中InvoiceTVO的变量定义为:

private int id;
private Date date;
private int customerId;
private int schoolId;
private float bookFee;
private float adminFee;
private float totalFee;

当我在此表上插入时,出现以下错误:

Hibernate: insert into INVOICE (INVOICE_DATE, CUSTOMER_ID, SCHOOL_ID, BOOK_FEE, ADMIN_FEE, TOTAL_FEE, ID) values (?, ?, ?, ?, ?, ?, ?)
50156 [AWT-EventQueue-0] WARN org.hibernate.util.JDBCExceptionReporter - SQL Error: 0, SQLState: 22001
50156 [AWT-EventQueue-0] ERROR org.hibernate.util.JDBCExceptionReporter - Data truncation: Data truncated for column 'ADMIN_FEE' at row 1
50156 [AWT-EventQueue-0] ERROR org.hibernate.event.def.AbstractFlushingEventListener - Could not synchronize database state with session

我尝试将adminFee的类型更改为double,但这也不起作用.问题是,Hibernate确实正确地执行了插入操作,并且将来的select语句可以返回当前的值集,但是这个错误阻止我对此发票进行进一步处理.

字段bookFee,adminFee和totalFee都应该是货币.它们在MySQL数据库中定义为十进制(5,2).

如何解决这个问题的任何帮助将不胜感激.

Answer 1

使用浮动或双倍的钱是绝对不可接受的,甚至可能是非法的(如违反法律或至少是法规).这需要修复,然后错误将消失.float的精度有限,根本无法准确表示大多数小数.

为了钱,总是,总是使用BigDecimal.

Answer 2

我会使用整数类型(int,long).永远不会有任何有趣的问题,你可以避免溢出.