Help me please

[Lebrun Jonathan]

I create a connection with Java and mm.mysql-1.0.
I 'm running and this the complier messages :

SQLException: General error: Access denied for user: '@localhost' to database 'link'
SQLState:     S1000
VendorError:  1044
java.lang.NullPointerException
 at conectiondb.ConnectionDB.<init>(ConnectionDB.java:41)
 at conectiondb.Application1.main(Application1.java:11)
Exception in thread "main" 

private Connection C;

  public ConnectionDB()throws IOException,SQLException{
/*    Properties info = new Properties();
    FileInputStream in = new FileInputStream("d:\\jdbc\\ConnectDB.properties");
    info.load(in);
    String url="jdbc:mysql://localhost:3306/link";*/
    try {
          Class.forName("org.gjt.mm.mysql.Driver").newInstance();
         }catch (Exception E) {
            System.err.println("Unable to load driver.");
            E.printStackTrace();
          }

    try {
         C = 
DriverManager.getConnection("jdbc:mysql://localhost:3306/link?user=root&password=dma633stk");
         }
            catch (SQLException E) {
              System.out.println("SQLException: " + E.getMessage());
              System.out.println("SQLState:     " + E.getSQLState());
              System.out.println("VendorError:  " + E.getErrorCode());
           }

Thanks for your assistance.