Connect problem with JDBC in javaBean and JSP

Поиск
Список
Период
Сортировка
От gaox
Тема Connect problem with JDBC in javaBean and JSP
Дата
Msg-id 000b01c211d3$565dba70$2100a8c0@mountor33
обсуждение исходный текст
Ответы Re: Connect problem with JDBC in javaBean and JSP  (tony <tony@animaproductions.com>)
Re: Connect problem with JDBC in javaBean and JSP  (Nookala Satish Kumar <javasatish@yahoo.com>)
Список pgsql-jdbc
Дерево обсуждения
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>&nbsp;</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

В списке pgsql-jdbc по дате отправления:

Предыдущее
От: Dave Cramer
Дата:
Сообщение: Re: Date in JDBC
Следующее
От: tony
Дата:
Сообщение: Re: Connect problem with JDBC in javaBean and JSP