File APIs for Java Developers
Manipulate DOC, XLS, PPT, PDF and many others from your application.
The moose likes JDBC and Relational Databases and the fly likes connection problem with mysql Big Moose Saloon
  Search | Java FAQ | Recent Topics | Flagged Topics | Hot Topics | Zero Replies
Register / Login
JavaRanch » Java Forums » Databases » JDBC and Relational Databases
Bookmark "connection problem with mysql" Watch "connection problem with mysql" New topic

connection problem with mysql

shosana lopez

Joined: Jul 09, 2004
Posts: 3
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 : 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 {
Connection con = DriverManager.getConnection("jdbc:mysql:///mysql");

System.out.println("Successfully connected to MySQL server...");

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

Joined: Jun 25, 2001
Posts: 17410

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.

An IDE is no substitute for an Intelligent Developer.
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");
I agree. Here's the link:
subject: connection problem with mysql
It's not a secret anymore!