- >     I am using eclipse .I tried to do java hibernate program for the first time but got the above error.please help me to solve it.
downloaded hibernate release 4.2.5 final.zip and added jar files to user library
antlr-2.7.7.jar
dom4j-1.6.1.jar
hibernate-commons-annotations-4.0.2.Final.jar
hibernate-core-4.2.5.Final.jar
hibernate-jpa-2.0-api-1.0.1.Final.jar
javassist-3.15.0-GA.jar
jboss-logging-3.1.0.GA.jar
jboss-transaction-api_1.1_spec-1.0.1.Final.jar
hibernate-entitymanager-4.2.5.Final.jar
hibernate-envers-4.2.5.Final.jar
hibernate-osgi-4.2.5.Final.jar
org.osgi.core-4.3.1.jar
 
 is these jar files enough for hibernate program.
 
 
hibernate.cfg.xml
          <?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>
           <!-- Related to the connection START -->
             <property name="connection.driver_class">oracle.jdbc.driver.OracleDriver
             </property>
           <property name="connection.url">jdbc:oracle:thin:@192.168.1.2:1521:xe</property>
             <property name="connection.user">system</property>
             <property name="connection.password">siddhu</property>
            <!-- Related to the connection END -->
             <!-- Related to hibernate properties START -->
             <property name="show_sql">true</property>
             <property name="dialet">org.hibernate.dialect.OracleDialect</property>
           <property name="hbm2ddl.auto">update</property>
           <!-- Related to hibernate properties END -->
           <!-- Related to mapping START -->
           <mapping resource="Details.hbm.xml"/>
           <!-- Related to the mapping END -->
          </session-factory>
          </hibernate-configuration>
Details.hbm.xml
             -       <hibernate-mapping>
             -       <class name="Details" table="stu">
             -       <id name="stNo" column="SNo">
            <generator class="assigned" /> 
            </id>
            <property name="stName" column="SName" /> 
            <property name="stAddress" /> 
            </class>
            </hibernate-mapping>
mainclass.java
    import org.hibernate.*;
    import org.hibernate.cfg.*;
    public class mainclass {
         public static void main(String[] args)
            {
                Configuration c = new Configuration();
                c.configure("hibernate.cfg.xml"); 
                SessionFactory factory = c.buildSessionFactory();
                Session session = factory.openSession();
              Details p=new Details();
                p.setStno(101);
                p.setStName ("iPhone");
                p.setStAddress("dfdsgdf");
                Transaction tx = session.beginTransaction();
                session.save(p);
                System.out.println("Object saved successfully.....!!");
                tx.commit();
                session.close();
                factory.close();
            }
    }
Details.java
    public class Details {
        private int stNo;
        private String stName;
        private String stAddress;
             public void setStno(int stNo)
             {
             this.stNo=stNo;
             }
             public int getStNo()
             {
             return stNo;
             }
             public void setStName(String stName)
             {
             this.stName=stName;
             }
             public String getStName()
             {
             return stName;
             }
             public void setStAddress(String stAddress)
             {
             this.stAddress=stAddress;
             }
             public String getStAddress()
             {
             return stAddress;
             }
    }
 Console Error
===========================================
             Sep 20, 2013 6:49:30 PM org.hibernate.annotations.common.Version <clinit>
           INFO: HCANN000001: Hibernate Commons Annotations {4.0.2.Final}
           Sep 20, 2013 6:49:30 PM org.hibernate.Version logVersion
             INFO: HHH000412: Hibernate Core {4.2.5.Final}
            Sep 20, 2013 6:49:30 PM org.hibernate.cfg.Environment <clinit>
            INFO: HHH000206: hibernate.properties not found
            Sep 20, 2013 6:49:30 PM org.hibernate.cfg.Environment buildBytecodeProvider
            INFO: HHH000021: Bytecode provider name : javassist
          Sep 20, 2013 6:49:30 PM org.hibernate.cfg.Configuration configure
           INFO: HHH000043: Configuring from resource: hibernate.cfg.xml
        Sep 20, 2013 6:49:30 PM org.hibernate.cfg.Configuration getConfigurationInputStream
            INFO: HHH000040: Configuration resource: hibernate.cfg.xml
          Sep 20, 2013 6:49:31 PM org.hibernate.internal.util.xml.DTDEntityResolver         resolveEntity
            WARN: HHH000223: Recognized obsolete hibernate namespace         http://hibernate.sourceforge.net/. Use namespace http://www.hibernate.org/dtd/ instead.    Refer to Hibernate 3.6 Migration Guide!
           Sep 20, 2013 6:49:31 PM org.hibernate.cfg.Configuration addResource
            INFO: HHH000221: Reading mappings from resource: Details.hbm.xml
           Exception in thread "main" org.hibernate.InvalidMappingException: Unable to read XML
            at     org.hibernate.internal.util.xml.MappingReader.readMappingDocument(MappingReader.java:109)
             at org.hibernate.cfg.Configuration.add(Configuration.java:488)
             at org.hibernate.cfg.Configuration.add(Configuration.java:484)
             at org.hibernate.cfg.Configuration.add(Configuration.java:657)
             at org.hibernate.cfg.Configuration.addResource(Configuration.java:740)
             at org.hibernate.cfg.Configuration.parseMappingElement(Configuration.java:2188)
            at org.hibernate.cfg.Configuration.parseSessionFactory(Configuration.java:2160)
            at org.hibernate.cfg.Configuration.doConfigure(Configuration.java:2140)
            at org.hibernate.cfg.Configuration.doConfigure(Configuration.java:2093)
            at org.hibernate.cfg.Configuration.configure(Configuration.java:2008)
            at mainclass.main(mainclass.java:9)
            Caused by: org.dom4j.DocumentException: Error on line 1 of document  : Content   is not  allowed in prolog. Nested exception: Content is not allowed in prolog.
            at org.dom4j.io.SAXReader.read(SAXReader.java:482)
            at     org.hibernate.internal.util.xml.MappingReader.readMappingDocument(MappingReader.java:78)
        ... 10 more