Postgre not able to connect

Hello I have downloaded the postgre driver for java, and tried to run
the following code;

import java.io.*;
import java.sql.*;

public class DataBase
{


  public static void main(String args[])
  {
    try {
      Class.forName("org.postgresql.Driver");
    } catch (ClassNotFoundException cnfe) {
      System.err.println("Couldn't find driver class:");
      cnfe.printStackTrace();
    }


    System.out.println("Testing");
  }
}


However, I get this output:
ed@desktop:~/jbproject$ javac Example1.java && java Example1
Checking if Driver is registered with DriverManager.
Couldn't find the driver!
Let's print a stack trace, and exit.
java.lang.ClassNotFoundException: org.postgresql.Driver
        at java.net.URLClassLoader$1.run(URLClassLoader.java:199)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:187)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:289)
        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:274)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:235)
        at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:302)
        at java.lang.Class.forName0(Native Method)
        at java.lang.Class.forName(Class.java:141)
        at Example1.main(Example1.java:10)

The driver is there, after reading the documentation I thought, perhaps
I have to rename the .jar file to postgres.jar:

ed@desktop:/usr/lib/j2sdk1.4.2$ find . | grep postgres
./jre/lib/ext/postgresql.jar
./lib/postgresql.jar

I am very confused as to what is going wrong.