java - Hibernate Session Factory issue -

i using hibernate 4 building application. while running application getting following error.

failed create sessionfactory object.java.lang.nosuchfielderror: trace exception in thread "main" java.lang.nullpointerexception

my code snippet is,

try{         session =  new dbconnection().getsession();         tx= session.begintransaction();                  ........                  ........  }catch(hibernateexception ex)     {         if (tx!=null) tx.rollback();         ex.printstacktrace();         session.close();         dbconnection.close();     }     catch(exception ex)     {         ex.printstacktrace();         session.close();     }     finally{         session.close(); // error shown in line while run time         dbconnection.close();         } 

dbconnection.java

public  dbconnection()        {                  try                 {                      configuration configuration = new configuration();                     configuration.configure();                     serviceregistry = new serviceregistrybuilder().applysettings(configuration.getproperties()).buildserviceregistry();                      factory = configuration.buildsessionfactory(serviceregistry);                  }                 catch (throwable ex) {                      system.err.println("failed create sessionfactory object." + ex);                 throw new exceptionininitializererror(ex);                  }        }      public session getsession()      {           return factory.opensession();     }       // call during shutdown    public static void close() {         factory.close();    } 

my configuration file :

<?xml version="1.0" encoding="utf-8"?> <!doctype hibernate-configuration system  "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">    <hibernate-configuration>      <session-factory>    <property name="hibernate.dialect">       org.hibernate.dialect.mysqldialect    </property>    <property name="hibernate.connection.driver_class">       com.mysql.jdbc.driver    </property>     <!-- assume test database name -->    <property name="hibernate.connection.url">       jdbc:mysql://localhost:3306/test    </property>    <property name="hibernate.connection.username">       root    </property>    <property name="hibernate.connection.password">       test    </property>  <property name="show_sql">true</property> <property name="format_sql">true</property> <property name="use_sql_comments">false</property>    <property name="hibernate.connection.pool_size">40</property>    </session-factory>   </hibernate-configuration> 

please guide me wrong code or jar file?

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answer: log4j cause of issue. removed log4j , added log4j-1.2.16.jar. gets fixed. thanks!

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in code new dbconnection() refers. need get/open session in hibernate org.hibernate.sessionfactory.sessionfactory. please check whether using sessionfactory or not.