java.lang.ClassCastException: oracle.sql.CLOB

[Firas Najjar]

Hi,
I am getting this error when I try to use oracle.sql.CLOB
Any help would be greatly appreciated

Here is my code (Inside DB.java)

public boolean updateClob(String selectstmt, String val) throws SQLException
 {
  if (selectstmt.equals("")) return false;
  try {
  Statement selStmt = conn.createStatement();
 
  selStmt.executeQuery(selectstmt +" for update");
 
  ResultSet rsc=selStmt.getResultSet();
  if (rsc.next()) {
  oracle.sql.CLOB clob = (oracle.sql.CLOB)rsc.getClob(1);
    //get output stream from the CLOB object
  OutputStream os = clob.getAsciiOutputStream();
  OutputStreamWriter osw = new OutputStreamWriter(os);

    //use that output stream to write character data to the Oracle data store 
    try {  osw.write(val.toCharArray()); } catch (IOException ex) { return false; }  
  //write data and commit
  try {  osw.flush();} catch (IOException ex) { return false; }
  try {  osw.close();} catch (IOException ex) { return false; }
  try {  os.close();} catch (IOException ex) { return false; }
    selStmt.close();
    rsc.close();
    return true;
  } // if value found  
  else {
    return false;
  }
  } catch (SQLException ex) {
        throw ex;
  }         
 }

And here is the error I am getting from catalina.out

java.lang.ClassCastException: oracle.sql.CLOB
at mdx.DB.updateClob(DB.java:116)
at org.apache.jsp.processEditBidItem_jsp._jspService(org.apache.jsp.processEditBidItem_jsp:174)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:319)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:868)
at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:663)
at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
at java.lang.Thread.run(Thread.java:595)

Thanks in advance

[Bear Bibeault]

Moved to the JDBC forum.

[stu derby]

http://www.oracle.com/technology/sample_code/tech/java/sqlj_jdbc/files/advanced/LOBSample/LOBSample.java.html

[Firas Najjar]

stu derby, Thanks for your reply.
This code is working on a resin environment; I moved to Tomcat5.5.12 and now
it is not working; it compiles correctly but when I try to use it gives this error.
I am not a JSP/JAVA expert and I did not write this code I just want it to work.
I am sure that the code in the link you send to is great but it will take a lot of time to figure it out.
I use this code when I want to insert or update to the Clob field.

Any help would greatly appreciated.
Thank you

[Reid M. Pinchback]

I think the problem is likely that you don't have the OracleResultSet. Most appservers have proxy classes for the JDBC driver. They don't have a choice in the matter if they want to manage a connection pool. If I'm correct, than that would mean the result set isn't returning an Oracle CLOB, it is returning a Resin wrapper around the Oracle CLOB. Whenever I've hit this problem before its always been because of a proxy class.
[ January 12, 2006: Message edited by: Reid M. Pinchback ]