How do I read environment variable in Tomcat?

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Ed Faulk - 20 Sep 2004 02:28 GMT

I have an application that needs to read the <env-entry> information. At
present I can use the following code to read the initialization parameters:

ServletConfig srvCfg = getServletConfig();
String sSomeData = servCfg.getInitParameter("SomeData");

But I'd like to be able to read the data from the <env-entry>. Obviously
this is a servlet and it's running under Tomcat 5.0.

Thanks,
Ed

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Real Gagnon - 20 Sep 2004 02:55 GMT

> But I'd like to be able to read the data from the <env-entry>.
> Obviously this is a servlet and it's running under Tomcat 5.0.

Context ctx = new InitialContext( );
String envVar = (String) ctx.lookup("java:comp/env/envVar");

See
<http://jakarta.apache.org/tomcat/tomcat-5.0-doc/jndi-resources-howto.html>

Bye.

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Real Gagnon from Quebec, Canada
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Ed Faulk - 20 Sep 2004 04:30 GMT

> > But I'd like to be able to read the data from the <env-entry>.
> > Obviously this is a servlet and it's running under Tomcat 5.0.
[quoted text clipped - 3 lines]
>
> See

<http://jakarta.apache.org/tomcat/tomcat-5.0-doc/jndi-resources-howto.html>

Yes, I tried that. Here's a sample piece of code:

import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import javax.naming.*;

public class EnvTest extends HttpServlet {

public void doGet(HttpServletRequest request, HttpServletResponse
response) throws ServletException, IOException {

PrintWriter out = response.getWriter();
String sName = "java:comp/env";

try {
Context initCtx = new InitialContext();
Context envCtx = (Context) initCtx.lookup(sName);
out.println("Got the environment context...");
sName = "MailServer";
String envVar = (String) envCtx.lookup(sName);
out.println("envVar: " + envVar);
}
catch (NamingException e) {
out.println("NamingException, problem looking up: \"" + sName +
"\"\nproblem is: " + e);
}
}
}

which results in the following:

NamingException, problem looking up: "java:comp/env"
problem is: javax.naming.NameNotFoundException: Name java:comp is not bound
in this Context

Any other ideas?

Ed

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How do I read environment variable in Tomcat?

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