Java installation error connecting to MySQL database

[mrs1179]

I have recently installed Java in my Ubuntu 9.04 environment so that I can teach myself Java. Basic Java programs work, but I am having trouble connecting to a MySQL database. I installed these packages using Synaptic Package Manager.

1.gsfonts-x11
2.java-common
3.odbcinst1debian1
4.sun-java6-bin
5.sun-java6-jdk
6.sun-java6-jre
7.unixodbc

After these packages were installed, I was not sure if I needed to do this, but I downloaded the MySQL connector from MySQL :: MySQL Connectors and installed in a directory called /home/mark/mysql/.

I then did "sudo gedit /etc/environment" and added a CLASSPATH to where I installed the connector:

CLASSPATH="/home/mark/mysql/mysql-connector-java-5.1.7/mysql-connector-java-5.1.7-bin.jar"

I found an example Java program from Using JDBC with MySQL, Getting Started and stripped it down even further to test the MySQL connection. This is the program I am running:

import java.sql.*;
public class Jdbctest {
  public static void main(String[] args){
    System.out.println("running Jdbctest.java");
    try {
      Statement stmt;
      //Register the JDBC driver for MySQL.
      Class.forName("com.mysql.jdbc.Driver");
      //Define URL of database server for database named mysql 
      // on the localhost with the default port number 3306.
      String url = "jdbc:mysql://localhost:3306/mysql";
      //Get a connection to the database for a
      // user named root with password carrot.
      // This user is the default administrator
      // having full privileges to do anything.
      Connection con = DriverManager.getConnection(url,"root", "carrot");
      //Display URL and connection information
      System.out.println("URL: " + url);
      System.out.println("Connection: " + con);
      //Get a Statement object
      stmt = con.createStatement();
      //Select from a table
      stmt.executeQuery("SELECT host, user FROM mysql.user ");
      con.close();
    }catch( Exception e ) {
      e.printStackTrace();
    }//end catch
  }//end main
}//end class Jdbctest

I am getting this error:

Exception in thread "main" java.lang.NoClassDefFoundError: Jdbctest
Caused by: java.lang.ClassNotFoundException: Jdbctest
	at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:252)
	at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:320)
Could not find the main class: Jdbctest.  Program will exit.

I am new to Linux, Ubuntu, Java and MySQL, so I have probably left out something that is very obvious. Any help would be greatly appreciated.

[mrs1179]

I have resolved the issue. I determined that after creating the CLASSPATH variable, it could no longer find the path to my class that I was running. I added ".:" to the beginning of CLASSPATH so that it would find my class in the current folder. The revised CLASSPATH looks like this:

CLASSPATH=".:/home/mark/mysql/mysql-connector-java-5.1.7/mysql-connector-java-5.1.7-bin.jar"