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JDBC: ClassNotFoundException  Class.forName()

Posted on 2004-08-03
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Last Modified: 2007-10-27
When trying to access my database I get the following error message:

INFO: JK2: ajp13 listening on /0.0.0.0:8010
Aug 3, 2004 9:07:06 AM org.apache.jk.server.JkMain start
INFO: Jk running ID=1 time=1/43  config=null
Aug 3, 2004 9:07:07 AM org.apache.catalina.startup.Catalina start
INFO: Server startup in 3733 ms
java.lang.ClassNotFoundException: usr/local/JDBCmySQL/mysql*/mysql/jdbc/Driver
        at java.lang.Class.forName0(Native Method)
        at java.lang.Class.forName(Class.java:219)
        at rtpm.EAKServlets.DBHandler.doPost(DBHandler.java:36)

Here is my database handler:

package rtpm.EAKServlets;

import java.io.*;
import java.net.*;

import javax.servlet.*;
import javax.servlet.http.*;
import java.util.*;
import java.sql.*;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

import rtpmEAKBeans.FormBean;

public class DBHandler extends HttpServlet {

    public void doPost (HttpServletRequest request,
      HttpServletResponse response) {
      try { // OBTAIN A DATABASE CONNECTION
         
          // Step 1: Load the JDBC driver          
          String driverName = "usr.local.JDBCmySQL.mysql*.mysql.jdbc.Driver";
          Class.forName(driverName, true, this.getClass().getClassLoader()).newInstance();
          // Class.forName("driverName", true, this.getClass().getClassLoader());
          Properties p = new Properties();
          p.put("user", "rmwijage");
          p.put("password", "NahumCh1");
                 
          // Step 2: Establish A connection to the database          
          String URL = "jdbc:mysql:///localhost/rtpmKenyaDB";
          Connection conn = null;  // conn is a Connection object
          conn = DriverManager.getConnection(URL,p);
                         
          String sql = "INSERT INTO rtpm_user(firstname, surname, " +
          "username, password1, password2, email, " +
          "sdp_code) VALUES (?, ?, ?, ?, ?, ?, ?)";
          PreparedStatement ps = conn.prepareStatement(sql);
         
          // Retreave the bean properties to be inserted into table rtpm_user
          FormBean f = (FormBean) request.getAttribute("formHandler");
         
          // Set the parameters in the prepared statement
          ps.setString(1, f.getFirstName());
          ps.setString(2, f.getLastName());
          ps.setString(3, f.getUserName());
          ps.setString(4, f.getPassword1());
          ps.setString(5, f.getPassword2());
          ps.setString(6, f.getEmail());
          ps.setString(7, f.getSdp());
         
          // Insert the row in the table
          ps.executeUpdate();

          // Close the connection
          ps.close();
          conn.close();    
      }
      catch (SQLException e) {
          // handle any errors
          System.out.println("SQLException: " + e.getMessage());
          System.out.println("SQLState: " + e.getSQLState());
          System.out.println("VendorError: " + e.getErrorCode());
          }
      catch (Exception e) {
      e.printStackTrace();
      }
     
      // Send the request back to success.jsp  
      try {
          getServletConfig().getServletContext().
            getRequestDispatcher("/success.jsp").
             forward(request, response);
      }
      catch (Exception e){}
     
   }
}


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Comment
Question by:Rrugemalira
  • 7
7 Comments
 
LVL 11

Assisted Solution

by:sompol_kiatkamolchai
sompol_kiatkamolchai earned 500 total points
ID: 11706928
usr.local.JDBCmySQL.mysql*.mysql.jdbc.Driver

This may not a correct driver class.

You can get driver form

http://dev.mysql.com/get/Downloads/Connector-J/mysql-connector-java-3.0.14-production.zip/from/http://gd.tuwien.ac.at/db/mysql/
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Expert Comment

by:sompol_kiatkamolchai
ID: 11707033
after you d/l mysql-connector-java-3.0.14-production.zip then extract the file mysql-connector-java-3.0.14-production-bin.jar to any directory in your hard drive then include that jar file into classpath.

then you can use this code to get a connection to database

import java.sql.*;

public class DatabaseConnection {
  public DatabaseConnection() {
  }

  public static Connection getConnection() {
    Connection con = null;
    try {
      Class.forName("com.mysql.jdbc.Driver");
      con = DriverManager.getConnection("jdbc:mysql:///localhost/rtpmKenyaDB", "rmwijage", "NahumCh1");
    }
    catch (Exception ex) {
      ex.printStackTrace();
    }
    return con;
  }
}
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Expert Comment

by:sompol_kiatkamolchai
ID: 11707070
for database url it should be

"jdbc:mysql://localhost/rtpmKenyaDB"
or
"jdbc:mysql://localhost/rtpmKenyaDB?user=rmwijage&password=NahumCh1"
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LVL 11

Expert Comment

by:sompol_kiatkamolchai
ID: 11707075
for more information, please read REAEME.txt in that zip file.

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Accepted Solution

by:
sompol_kiatkamolchai earned 500 total points
ID: 11707125
Or try this. if you want to use your code. and open connection in jsp file.

package rtpm.EAKServlets;

import java.io.*;
import java.net.*;

import javax.servlet.*;
import javax.servlet.http.*;
import java.util.*;
import java.sql.*;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import com.mysql.jdbc.Driver;

import rtpmEAKBeans.FormBean;

public class DBHandler extends HttpServlet {

    public void doPost (HttpServletRequest request,
      HttpServletResponse response) {
      try { // OBTAIN A DATABASE CONNECTION
         
          // Step 1: Load the JDBC driver          
          Class.forName("com.mysql.jdbc.Driver");
                 
          // Step 2: Establish A connection to the database          
           Connection conn = DriverManager.getConnection("jdbc:mysql:///localhost/rtpmKenyaDB", "rmwijage", "NahumCh1");
                         
          String sql = "INSERT INTO rtpm_user(firstname, surname, " +
          "username, password1, password2, email, " +
          "sdp_code) VALUES (?, ?, ?, ?, ?, ?, ?)";
          PreparedStatement ps = conn.prepareStatement(sql);
         
          // Retreave the bean properties to be inserted into table rtpm_user
          FormBean f = (FormBean) request.getAttribute("formHandler");
         
          // Set the parameters in the prepared statement
          ps.setString(1, f.getFirstName());
          ps.setString(2, f.getLastName());
          ps.setString(3, f.getUserName());
          ps.setString(4, f.getPassword1());
          ps.setString(5, f.getPassword2());
          ps.setString(6, f.getEmail());
          ps.setString(7, f.getSdp());
         
          // Insert the row in the table
          ps.executeUpdate();

          // Close the connection
          ps.close();
          conn.close();    
      }
      catch (SQLException e) {
          // handle any errors
          System.out.println("SQLException: " + e.getMessage());
          System.out.println("SQLState: " + e.getSQLState());
          System.out.println("VendorError: " + e.getErrorCode());
          }
      catch (Exception e) {
      e.printStackTrace();
      }
     
      // Send the request back to success.jsp  
      try {
          getServletConfig().getServletContext().
            getRequestDispatcher("/success.jsp").
             forward(request, response);
      }
      catch (Exception e){}
     
   }
}
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Expert Comment

by:sompol_kiatkamolchai
ID: 11707151
sorry. replace

          // Step 2: Establish A connection to the database          
           Connection conn = DriverManager.getConnection("jdbc:mysql:///localhost/rtpmKenyaDB", "rmwijage", "NahumCh1");

with this

          // Step 2: Establish A connection to the database          
           Connection conn = DriverManager.getConnection("jdbc:mysql://localhost/rtpmKenyaDB", "rmwijage", "NahumCh1");

or this if above does not work

          // Step 2: Establish A connection to the database          
           Connection conn = DriverManager.getConnection"jdbc:mysql://localhost/rtpmKenyaDB?user=rmwijage&password=NahumCh1", "rmwijage", "NahumCh1");

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LVL 11

Expert Comment

by:sompol_kiatkamolchai
ID: 11707170
Hope all my comments would help you. :)
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