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connection problem with mysql

shosana lopez
Greenhorn

Joined: Jul 09, 2004
Posts: 3
hi,
i'm using j2sdk1.4.2 & mysql 3.x and i'm having a problem with connecting these two. i'm using the latest connector, which mysql-connector-java-3.0.14-production-bin.jar, and i followed all the steps for installing this driver. i've already set the classpath to where the connector is. but i'm still having some problems.
this error occurs :
unable to connect to any hosts due to exception : java.net.ConnectException: Connectionrefused: connect

what should i do?
here's the code i've been using to check the connection

import java.sql.*;

public class JdbcExample1 {

public static void main(String args[]) {

try {
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection con = DriverManager.getConnection("jdbc:mysql:///mysql");

if(!con.isClosed())
System.out.println("Successfully connected to MySQL server...");

} catch(Exception e) {
System.err.println("Exception: " + e.getMessage());
e.printStackTrace();
}
} }
Tim Holloway
Saloon Keeper

Joined: Jun 25, 2001
Posts: 16308
    
  22

I think you overdid the slashes in your URL, but that's a different problem.

First, check to make sure that the MySQL server is running (just in case!)

Secondly, check to see if it's listening on the tcp/ip port that your JDBC driver is expecting to talk on (it may be 1033 for MySQL, but I'd check, 'cause I don't rightly remember). netstat is your friend.

Third, make sure MySQL wishes to talk to you. I think you can get a "connection refused" if it checks your host address and finds that that host isn't authorised to talk to the database you wish to use.

*** WARNING *** The messages that MySQL return in the above case LIE. MySQL does a reverse lookup on the incoming IP address and uses THAT hostname to validate, despite reporting the failure being against YOUR hostname.

r maybe it's vice versa. Every time I set up a MySQL server I get into fights with it over that. MySQL does provide a utility program to lookup hostnames, BTW. It can be used to help you.


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Stefan Wagner
Ranch Hand

Joined: Jun 02, 2003
Posts: 1923

... and don't you need a username/ password to connect?

DriverManager.getConnection("jdbc:mysql:/mysql", "admin", "supersecret");


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