0 Replies Latest reply on Mar 10, 2005 6:14 PM by julia zhou

    java.lang.ClassCastException when retrieving Object from Dat

    julia zhou Newbie

      Hi there,

      I am having problmes to retrieve Object out of database. I am using Jboss 3.2.6, Sybase ASA 8.0.2.

      We have an entity bean, one of the data memeber is a serializable Object, say Object_A. Entity bean was created successfully. Data was inserted into Database without problems. But when I tried to retrieve the data through direct JDBC from the database. I got ClassCastException. If I retrieve the data by calling the entity bean finder methods, everything worked fine.

      I am doing the evaluation for our product to see if we can migrate to Jboss. Many applications of our product make direct JDBC calls to the database to retrieve the data that has been written to DB through entity beans. Because of the big number of applications, it's almost impossible to change the applications to call the entity bean finder. We didn't have any problem with our existing AS.

      The jdbc/sql mapping for object is as follows:


      <java-type>java.lang.Object</java-type>
      <jdbc-type>BINARY</jdbc-type>
      <sql-type>IMAGE</sql-type>

      The original mapping coming with Jboss was:

      <java-type>java.lang.Object</java-type>
      <jdbc-type>JAVA_OBJECT</jdbc-type>
      <sql-type>IMAGE</sql-type>

      I had to change the mapping because the version of the Sybase we are using doesn't support JDK1.4, while our application uses JDK1.4.

      The code to read Object_A:
      protected static Object_A getHashtable( InputStream is ) throws IOException {
      if( is == null ) {
      return new Object_A();
      }

      ObjectInputStream ois = new ObjectInputStream(is);
      Object_A sht = null;
      try {
      sht = (Object_A)ois.readObject();
      ois.close();
      is.close();
      return sht;
      } catch( ClassNotFoundException cnfe ) {
      LogSystem.logError(Level.WARNING, " ", cnfe);
      return new Object_A();
      }
      }

      The code in bold is the line that causes the exception below:

      09:17:37,651 ERROR [STDERR] java.lang.ClassCastException
      09:17:37,651 ERROR [STDERR] at product.application.getHashtable(DBUtility.java:601)
      09:17:37,661 ERROR [STDERR] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
      09:17:37,661 ERROR [STDERR] at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
      09:17:37,661 ERROR [STDERR] at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
      09:17:37,661 ERROR [STDERR] at java.lang.reflect.Method.invoke(Unknown Source)
      09:17:37,661 ERROR [STDERR] at org.jboss.ejb.StatelessSessionContainer$ContainerInterceptor.invoke(StatelessSessionContainer.java:683)
      09:17:37,661 ERROR [STDERR] at org.jboss.resource.connectionmanager.CachedConnectionInterceptor.invoke(CachedConnectionInterceptor.java:186)
      09:17:37,661 ERROR [STDERR] at org.jboss.ejb.plugins.StatelessSessionInstanceInterceptor.invoke(StatelessSessionInstanceInterceptor.java:72)
      09:17:37,661 ERROR [STDERR] at org.jboss.ejb.plugins.AbstractTxInterceptor.invokeNext(AbstractTxInterceptor.java:84)
      09:17:37,661 ERROR [STDERR] at org.jboss.ejb.plugins.TxInterceptorCMT.runWithTransactions(TxInterceptorCMT.java:315)
      09:17:37,661 ERROR [STDERR] at org.jboss.ejb.plugins.TxInterceptorCMT.invoke(TxInterceptorCMT.java:148)
      09:17:37,661 ERROR [STDERR] at org.jboss.ejb.plugins.SecurityInterceptor.invoke(SecurityInterceptor.java:111)
      09:17:37,661 ERROR [STDERR] at org.jboss.ejb.plugins.LogInterceptor.invoke(LogInterceptor.java:191)
      09:17:37,661 ERROR [STDERR] at org.jboss.ejb.plugins.ProxyFactoryFinderInterceptor.invoke(ProxyFactoryFinderInterceptor.java:122)
      09:17:37,661 ERROR [STDERR] at org.jboss.ejb.StatelessSessionContainer.internalInvoke(StatelessSessionContainer.java:331)
      09:17:37,661 ERROR [STDERR] at org.jboss.ejb.Container.invoke(Container.java:709)
      09:17:37,661 ERROR [STDERR] at sun.reflect.GeneratedMethodAccessor91.invoke(Unknown Source)
      09:17:37,661 ERROR [STDERR] at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
      09:17:37,661 ERROR [STDERR] at java.lang.reflect.Method.invoke(Unknown Source)
      09:17:37,661 ERROR [STDERR] at org.jboss.mx.server.ReflectedDispatcher.dispatch(ReflectedDispatcher.java:60)
      09:17:37,661 ERROR [STDERR] at org.jboss.mx.server.Invocation.dispatch(Invocation.java:62)
      09:17:37,661 ERROR [STDERR] at org.jboss.mx.server.Invocation.dispatch(Invocation.java:54)
      09:17:37,661 ERROR [STDERR] at org.jboss.mx.server.Invocation.invoke(Invocation.java:82)
      09:17:37,661 ERROR [STDERR] at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:197)
      09:17:37,661 ERROR [STDERR] at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:473)
      09:17:37,661 ERROR [STDERR] at org.jboss.invocation.jrmp.server.JRMPInvoker.invoke(JRMPInvoker.java:360)
      09:17:37,661 ERROR [STDERR] at sun.reflect.GeneratedMethodAccessor88.invoke(Unknown Source)
      09:17:37,661 ERROR [STDERR] at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
      09:17:37,661 ERROR [STDERR] at java.lang.reflect.Method.invoke(Unknown Source)
      09:17:37,661 ERROR [STDERR] at sun.rmi.server.UnicastServerRef.dispatch(Unknown Source)
      09:17:37,661 ERROR [STDERR] at sun.rmi.transport.Transport$1.run(Unknown Source)
      09:17:37,661 ERROR [STDERR] at java.security.AccessController.doPrivileged(Native Method)
      09:17:37,661 ERROR [STDERR] at sun.rmi.transport.Transport.serviceCall(Unknown Source)
      09:17:37,661 ERROR [STDERR] at sun.rmi.transport.tcp.TCPTransport.handleMessages(Unknown Source)
      09:17:37,671 ERROR [STDERR] at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(Unknown Source)
      09:17:37,671 ERROR [STDERR] at java.lang.Thread.run(Unknown Source)

      Your help will be very much appreciated!

      Thanks,
      Julia.