java.lang.ClassCastException:java.lang.NoClassDefFoundError

Posted in 2000

Topics: Connectivity: ODBC / JDBC / .NET, Security, Permissions & Auditing, Java & JDBC Development

Patrick Pinchera — Fri, 07 Jul 2000 12:09:11 GMT — source: Informix-list mailing list archive (1991-1998)

I'm trying to get an applet to run under Netscape Enterprise Server 3.6. The applet worked fine until I tried to use JDBC to talk to my Informix database. When the applet tries to connect to the database, I get a java.lang.ClassCastException:java.lang.NoClassDefFoundError error. I can get a Java appletthat uses JDBC to connect to the Informix database successfully, but only when it is run standalone (outside of NES 3.6). Once I try to run it from the server, I get this error. I really think it has something to do with the server configuration. I set my classpath (in config/obj.conf): classpath="/opt/netscape/suitespot/js/samples:/opt/netscape/suitespot/plugins/java/classes/serv3_0.zip:/opt/netscape/suitespot/plugins/java/local-classes:/opt/netscape/suitespot/plugins/java/classes/servlet3_5.zip:/opt2/informix/ifxjava_home/lib/ifxjdbc.jar" I had to unzip the files in the ifxjdbc.jar file and put them in /opt/netscape/suitespot/plugins/java/local-classes to get the Class.forName(ifxDriver); to work successfully. Now when the code tries: conn = (Connection)DriverManager.getConnection(connURL); I get this java.lang.ClassCastException:java.lang.NoClassDefFoundError error. Any pointers you may have would be especially helpful. If there is a better newsgroup for this question, please let me know. I have searched a *lot* of newsgroups looking for the problem. Thanks, Pat pat@pinchera.com Here is the section of code that uses JDBC: private boolean connectToDBServer( ServletOutputStream out ) throws ServletException, IOException { try { String ifxDriver = "com.informix.jdbc.IfxDriver"; // Register the INFORMIX-JDBC driver out.println("Calling Class.forName(" + ifxDriver + ").... "); Class.forName(ifxDriver); out.println("Class.forName(" + ifxDriver + ") SUCCESS. "); out.println("Trying to CONNECT to the database server: connURL = '" + connURL + "' "); // Get a connection to the database server conn = (Connection)DriverManager.getConnection(connURL); out.println("Driver loaded...and connection established"); return(true); } catch (ClassNotFoundException e) { out.println("Could not load the database driver: " + e.getMessage() + ".... "); out.println("e = " + e + " "); out.println("e.toString() = " + e.toString() + " "); return(false); } catch (SQLException e) { out.println("SQLException caught: " + e.getMessage() + ".... "); return(false); } catch (Exception e) { out.println("Could not connect to database server.... "); out.println("e.getMessage() = '" + e.getMessage() + "' "); out.println("e = " + e + " "); return(false); } } // end of connectToDBServer method And the output is this: Calling Class.forName(com.informix.jdbc.IfxDriver).... Class.forName(com.informix.jdbc.IfxDriver) SUCCESS. Trying to CONNECT to the database server: connURL = 'jdbc:informix-sqli://www.hostname.com:2055/dbname:INFORMIXSERVER=servername;user=username;password=myPassword' Could not connect to database server.... e.getMessage() = 'java.lang.NoClassDefFoundError' e = java.lang.ClassCastException: java.lang.NoClassDefFoundError