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Connect problem with JDBC in javaBean and JSP - Mailing list pgsql-jdbc

From	gaox
Subject	Connect problem with JDBC in javaBean and JSP
Date	June 12, 2002 10:57:48
Msg-id	000b01c211d3$565dba70$2100a8c0@mountor33 Whole thread Raw
Responses	Re: Connect problem with JDBC in javaBean and JSP Re: Connect problem with JDBC in javaBean and JSP
List	pgsql-jdbc

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I try to write a bean to deal with all the operation of the database. Here are the codes:

import java.sql.*;
import java.util.*;

public class ConnectDB {
String error;
Connection con;

public void connect () throws ClassNotFoundException,
                            SQLException,
                            Exception {
  try {
   Class.forName("org.postgresql.Driver");
   con = DriverManager.getConnection("jdbc:postgresql:test","postgres","");
  }
  catch (ClassNotFoundException cnfe) {
   error = "ClassNotFoundException: Could not locate DB driver.";
   throw new ClassNotFoundException (error);
  }
  catch (SQLException sqle) {
   error = "SQLException: Could not connect to database.";
   throw new Exception (error);
  }
  catch (Exception e) {
   error = "Exception: An unknown error occurred while connecting to database.";
   throw new Exception (error);
  }
}

public void disconnect () throws SQLException {
  try {
   if ( con != null ) {
    con.close();
   }
  }
  catch (SQLException sqle) {
   error = "SQLException: Unable to close the database connection.";
   throw new SQLException (error);
  }
}

public ResultSet viewDatabase () throws SQLException, Exception {
  ResultSet rs = null;
  try {
   String queryString = "Select * From test;";
   Statement stmt = con.createStatement();
   rs = stmt.executeQuery(queryString);
  }
  catch (SQLException sqle) {
   error = "SQLException : Could not execute the query.";
   throw new SQLException (error);
  }
  catch (Exception e) {
   error = "Exception: An unknown error occurred while test.";
   throw new Exception (error);
  }
  return rs;
}
}

and the JSP is :

<%@ page language="java" import="java.sql.*, java.io.*, java.util.*" %>
<%@ page contentType="text/html;charset=gb2312"%>
<jsp:useBean id="test" class="ConnectDB" />

<html>
<head><title> test database </title></head>

<body>
<table width="85%" border="1">
<%
test.connect ();

ResultSet rs = test.viewDatabase ();

while (rs.next()) {
%>
<tr>
<td><%=rs.getInt("i")%></td>
<td><%=rs.getString("name")%></td>
</tr>
<%
}

test.disconnect ();
%>
</table>
<p> </p>
</body>
</html>

The environment is Redhat 7.2, postgreSQL 7.2, j2sdk1.4.0, Tomcat 4.0.3

and the parameter CLASSPATH contains the /usr/local/pgsql/share/pgjdbc2.jar

While I browse the page, it is said

javax.servlet.ServletException: ClassNotFoundException: Could not locate DB driver.
at org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:463)
at org.apache.jsp.list$jsp._jspService(list$jsp.java:134)
........

However, I can run my java application to connect the database and show the

records in it well. What's wrong? Thanks a lot for help!

yours Xiang Gao

pgsql-jdbc by date:

From: Dave Cramer
Date: 11 June 2002, 19:34:50
Subject: Re: Date in JDBC

From: tony
Date: 12 June 2002, 11:53:32
Subject: Re: Connect problem with JDBC in javaBean and JSP

Connect problem with JDBC in javaBean and JSP - Mailing list pgsql-jdbc

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