Question

在hibernate.hbm.xml文件中使用属性版本和时间戳并运行程序时，我得到一个例外。如果删除version属性，程序运行正常，但同时使用两者我都会收到运行时错误。

hibernate.hbm.xml文件

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="Product.Product" table="Product">
    <id name="productId" column="pId">
        <generator class="assigned"/>
    </id>
    <timestamp name="ts" column="dateTime" />
    <version name="v" column="version"/>
    <property name="productName" column="pName"  length="50"/>
    <property name="productPrice" column="pPrice" />
</class>
</hibernate-mapping>

HibernateUtil类

public class HibernateUtil {

public static void main(String[] args) {
    Configuration c = new Configuration();
    c.configure("hibernate.cfg.xml");
    SessionFactory factory = c.buildSessionFactory();
    Session session = factory.openSession();
    Product p = new Product();
    p.setProductId(1001);
    p.setProductName("Sony");
    p.setProductPrice(2000);
    Transaction tx = session.beginTransaction();
    session.save(p);
    tx.commit();
    System.out.println("Object is create Success fully...");
    session.close();
    factory.close();
}

}

错误

Exception in thread "main" org.hibernate.InvalidMappingException: Unable to read XML
at org.hibernate.internal.util.xml.MappingReader.legacyReadMappingDocument(MappingReader.java:375)
at org.hibernate.internal.util.xml.MappingReader.readMappingDocument(MappingReader.java:304)
at org.hibernate.cfg.Configuration.add(Configuration.java:516)
at org.hibernate.cfg.Configuration.add(Configuration.java:512)
at org.hibernate.cfg.Configuration.add(Configuration.java:686)
at org.hibernate.cfg.Configuration.addResource(Configuration.java:769)
at org.hibernate.cfg.Configuration.parseMappingElement(Configuration.java:2255)
at org.hibernate.cfg.Configuration.parseSessionFactory(Configuration.java:2227)
at org.hibernate.cfg.Configuration.doConfigure(Configuration.java:2207)
at org.hibernate.cfg.Configuration.doConfigure(Configuration.java:2160)
at org.hibernate.cfg.Configuration.configure(Configuration.java:2075)
at Product.HibernateUtil.main(HibernateUtil.java:23)

Caused by: org.xml.sax.SAXParseException; lineNumber: 12; columnNumber: 13; The content of element type "class" must match "(meta*,subselect?,cache?,synchronize*,comment?,tuplizer*,(id|composite-id),discriminator?,natural-id?,(version|timestamp)?,(property|many-to-one|one-to-one|component|dynamic-component|properties|any|map|set|list|bag|idbag|array|primitive-array)*,((join*,subclass*)|joined-subclass*|union-subclass*),loader?,sql-insert?,sql-update?,sql-delete?,filter*,fetch-profile*,resultset*,(query|sql-query)*)".
at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.createSAXParseException(ErrorHandlerWrapper.java:203)
at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.error(ErrorHandlerWrapper.java:134)
at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:396)
at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:327)
at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:284)
at com.sun.org.apache.xerces.internal.impl.dtd.XMLDTDValidator.handleEndElement(XMLDTDValidator.java:1994)
at com.sun.org.apache.xerces.internal.impl.dtd.XMLDTDValidator.endElement(XMLDTDValidator.java:879)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanEndElement(XMLDocumentFragmentScannerImpl.java:1782)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(XMLDocumentFragmentScannerImpl.java:2967)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:602)
at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.next(XMLNSDocumentScannerImpl.java:112)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:505)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:841)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:770)
at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:141)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1213)
at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:643)
at org.dom4j.io.SAXReader.read(SAXReader.java:465)
at org.hibernate.internal.util.xml.MappingReader.legacyReadMappingDocument(MappingReader.java:325)

Answer 1

正如您所说，您同时使用version和timestamp，

在错误行中，您可以看到(version|timestamp)?，表示其中两个是独占的。我很遗憾地告诉您，您只能在<class>内使用其中一个。

您可以阅读Hibernate documentation：

Hibernate提供了两种不同的机制来存储版本信息，专用版本号或时间戳。

其中两个用于提供版本机制，您只需选择使用哪个;）

使用版本和时间戳我得到一个SAXParseException

1 个答案: