Context inCtx;
		DataSource ds;
		try {
			inCtx = new InitialContext();
			Context enCtx = (Context) inCtx.lookup("java:comp/env");
			ds = (DataSource) enCtx.lookup("jdbc/survey");
			text.setText(""+ds);
		} catch (NamingException e1) {
			e1.printStackTrace();
			text.setText(e1.getMessage());
		}

 <resource-ref>
    <res-ref-name>jdbc/survey</res-ref-name>
    <res-type>javax.sql.DataSource</res-type>
    <res-auth>Container</res-auth>
    <res-sharing-scope>Shareable</res-sharing-scope>
  </resource-ref>

javax.naming.ConfigurationException: A JNDI operation on a "java:" name cannot be completed because the server runtime is not able to associate the operation's thread with any J2EE application component.  This condition can occur when the JNDI client using the "java:" name is not executed on the thread of a server application request.  Make sure that a J2EE application does not execute JNDI operations on "java:" names within static code blocks or in threads created by that J2EE application.  Such code does not necessarily run on the thread of a server application request and therefore is not supported by JNDI operations on "java:" names. [Root exception is javax.naming.NameNotFoundException: Name jdbc not found in context "java:comp/env".]