在独立应用程序的休眠中配置 sessionFactory

Question

我正在尝试制作一个第 3 方简单的独立/摇摆应用程序，该应用程序使用休眠来连接另一个应用程序的数据库，所以这就是我所做的：

1- 使用的罐子：

hibernate-core-3.5.1-Final
hibernate-entitymanager-3.5.1-Final
hibernate-jpa-2.0-api-1.0.0.Final
hibernate-annotations-3.5.1-Final
hibernate-commons-annotations-3.2.0.Final
dom4j-1.6.1
slf4j-api-1.6.4
slf4j-log4j12-1.6.4
log4j-1.2.16.jar
commons-collections-3.2
jta-1.1
mysql-connector-java-5.1.14 (or compatible connector with your DB)
commons-logging-1.1.1
commons-collections-3.2

2- hibernate.cfg.xml（在 src 文件夹内）：

<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
   <session-factory>

            <property name="show_sql">true</property>
            <property name="format_sql">true</property>
            <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
            <property name="connection.url">jdbc:mysql://127.0.0.1:3306/myapp</property>
            <property name="connection.username">myuser</property>
            <property name="connection.password">mypass</property>
            <property name="dialect">org.hibernate.dialect.MySQLDialect</property>
            <property name="current_session_context_class">thread</property>

   </session-factory>
</hibernate-configuration>

3- SessionFactoryHelper：

public class SessionFactoryHelper {

    private static final SessionFactory sessionFactory;

    static {
        try {
            /*
             * Build a SessionFactory object from session-factory configuration
             * defined in the hibernate.cfg.xml file. In this file we register
             * the JDBC connection information, connection pool, the hibernate
             * dialect that we used and the mapping to our hbm.xml file for each
             * POJO (Plain Old Java Object).
             */
            sessionFactory = new Configuration().configure()
                    .buildSessionFactory();
        } catch (Throwable e) {
            System.err.println("Error in creating SessionFactory object."
                    + e.getMessage());
            throw new ExceptionInInitializerError(e);
        }
    }

    /*
     * A static method for other application to get SessionFactory object
     * initialized in this helper class.
     */
    public static SessionFactory getSessionFactory() {
        return sessionFactory;
    }
}

4- 示例查询：

Session session = SessionFactoryHelper.getSessionFactory()
            .getCurrentSession();
    session.beginTransaction();
    int count = (Integer) session.createSQLQuery(
            "select count(*) from users").uniqueResult();
    session.getTransaction().commit();
    System.out.println("Users Count: " + count);

在运行应用程序时，我得到以下异常：

Error in creating SessionFactory object.invalid configuration
Exception in thread "main" java.lang.ExceptionInInitializerError
    at com.xeno.xecamp.desktopManagement.SessionFactoryHelper.<clinit>(SessionFactoryHelper.java:24)
    at com.myapp.Main.main(Main.java:9)
Caused by: org.hibernate.MappingException: invalid configuration
    at org.hibernate.cfg.Configuration.doConfigure(Configuration.java:1579)
    at org.hibernate.cfg.Configuration.configure(Configuration.java:1520)
    at org.hibernate.cfg.Configuration.configure(Configuration.java:1506)
    at com.xeno.xecamp.desktopManagement.SessionFactoryHelper.<clinit>(SessionFactoryHelper.java:19)
    ... 1 more
Caused by: org.xml.sax.SAXParseException: Document is invalid: no grammar found.
    at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.createSAXParseException(ErrorHandlerWrapper.java:195)
    at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.error(ErrorHandlerWrapper.java:131)
    at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:384)
    at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:318)
    at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.scanStartElement(XMLNSDocumentScannerImpl.java:250)
    at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl$NSContentDriver.scanRootElementHook(XMLNSDocumentScannerImpl.java:626)
    at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(XMLDocumentFragmentScannerImpl.java:3103)
    at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$PrologDriver.next(XMLDocumentScannerImpl.java:922)
    at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:648)
    at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.next(XMLNSDocumentScannerImpl.java:140)
    at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:511)
    at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:808)
    at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:737)
    at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:119)
    at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1205)
    at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:522)
    at org.dom4j.io.SAXReader.read(SAXReader.java:465)
    at org.hibernate.cfg.Configuration.doConfigure(Configuration.java:1576)
    ... 4 more

谁能告诉我我的配置有什么问题？

Answer 1

这个问题根本与 Hibernate 无关，而是与 XML 结构有关。

SAX Reader 由 Hibernate 设置为使用验证 (org.hibernate.util.XMLHelper#createSAXReader(String,List,EntityResolver)

这样就少了：

SAXParserFactory factory = SAXParserFactory.newInstance();
    factory.setValidating(true);
    factory.setNamespaceAware(true);

Java dosc 说

方法 setValidating(boolean) - 请求 DTD 验证并在不存在 DTD 时导致失败。如果您只需要模式验证而不需要 DTD 验证，请使用 setValidating(false)。

你的错误说得很清楚：

Caused by: org.xml.sax.SAXParseException: Document is invalid: no grammar found.

In this tutorial you will find all required information about hibernate conf file.

要修复它，您需要添加：

<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">

Answer 2

您没有在 hibernate.cfg.xml 中声明任何 DTD

The message is saying that you are trying to validate the document, but no DTD has been declared, because no DOCTYPE declaration is present.