Immediate HELP in Tomcat 5 to Postgresql 7.4 database connectivity problem

Question

Hi,
I failed to connect Tomcat 5.0.24 with Postgresql
7.4.2. The files created by me and the changes i had
made in the existing files are rates.jsp,
conversionDAO.java, web.xml and server.xml. The error
message on the top of the rest of it was "The value of
useBean class attribute converter.conversionDAO is
invalid". So far I found out that the coding for
database connectivity purpose in conversionDAO.java
cause the error. Another thing is Postgresql jdbc
driver is required to set in the CLASSPATH for the
java file to access the Postgresql database. I don't
know where should I put it in Tomcat for web
application. Anyway, I put it in
$CATALINA_HOME/shared/lib according the book i
refered. I do the database connectivity coding refer
to the Tomcat Kick Start book from Sams Publishing.
Below are the coding involved, please show me the
mistake i had made. Thank you.
----server.xml----
<Context path="/database"
docBase="${catalina.home}/webapps/database" debug="0"
reload="true">
<ResourceParams name="jdbc/conversion">
<parameter>
<name>username</name>
<value>myusername</value>
</parameter>
<parameter>
<name>password</name>
<value>mypassword</value>
</parameter>
<parameter>
<name>driverClassName</name>
<value>org.postgresql.Driver</value>
</parameter>
<parameter>
<name>url</name>
<value>jdbc:postgresql://localhost/conversion</value>
</parameter>
</ResourceParams>
</Context>
----web.xml----
<servlet>
<servlet-name>conversionDAO</servlet-name>
<servlet-class>converters.conversionDAO</servlet-class>
</servlet>
<resource-ref>
<res-ref-name>jdbc/conversion</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>
----conversionDAO.java----
public conversionDAO() throws SQLException,
NamingException
Context init = new InitialContext();
Context ctx = (Context)
init.lookup("java:comp/env");
DataSource ds = (DataSource)
ctx.lookup("jdbc/conversion");
con = ds.getConnection();
select = con.prepareStatement(
"SELECT rate FROM Exchange WHERE src= ? AND dst =

Answer 1

Immediate HELP in Tomcat 5 to Postgresql 7.4 database connectivity problem (cont.)
Errors log
2004-06-06 01:07:53 StandardContext[servlets-examples]SessionListener: contextDestroyed()
2004-06-06 01:07:53 StandardContext[servlets-examples]ContextListener: contextDestroyed()
2004-06-06 01:07:53 StandardContext[jsp-examples]SessionListener: contextDestroyed()
2004-06-06 01:07:53 StandardContext[jsp-examples]ContextListener: contextDestroyed()
2004-06-06 01:07:59 StandardContext[balancer]org.apache.webapp.balancer.BalancerFilter: init(): ruleChain: [org.apache.webapp.balancer.RuleChain: [org.apache.webapp.balancer.rules.URLStringMatchRule: Target string: News / Redirect URL: http://www.cnn.com], [org.apache.webapp.balancer.rules.RequestParameterRule: Target param name: paramName / Target param value: paramValue / Redirect URL: http://www.yahoo.com], [org.apache.webapp.balancer.rules.AcceptEverythingRule: Redirect URL: http://jakarta.apache.org]]
2004-06-06 01:08:00 StandardContext[jsp-examples]ContextListener: contextInitialized()
2004-06-06 01:08:00 StandardContext[jsp-examples]SessionListener: contextInitialized()
2004-06-06 01:08:00 StandardContext[servlets-examples]ContextListener: contextInitialized()
2004-06-06 01:08:00 StandardContext[servlets-examples]SessionListener: contextInitialized()
2004-06-06 01:08:01 StandardWrapperValve[jsp]: Servlet.service() for servlet jsp threw exception
org.apache.jasper.JasperException: /rates/rates.jsp(5,0) The value for the useBean class attribute converters.conversionDAO is invalid.
     at org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:39)
     at org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:357)
     at org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:141)
     at org.apache.jasper.compiler.Generator$GenerateVisitor.visit(Generator.java:1217)
     at org.apache.jasper.compiler.Node$UseBean.accept(Node.java:1116)
     at org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2163)
     at org.apache.jasper.compiler.Node$Visitor.visitBody(Node.java:2213)
     at org.apache.jasper.compiler.Node$Visitor.visit(Node.java:2219)
     at org.apache.jasper.compiler.Node$Root.accept(Node.java:456)
     at org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2163)
     at org.apache.jasper.compiler.Generator.generate(Generator.java:3261)
     at org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:244)
     at org.apache.jasper.compiler.Compiler.compile(Compiler.java:439)
     at org.apache.jasper.compiler.Compiler.compile(Compiler.java:422)
     at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:507)
     at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:274)
     at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292)
     at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236)
----more----