Conexiones para SQL en Java

SQL Server

   DriverManager.registerDriver(new com.microsoft.sqlserver.jdbc.SQLServerDriver());
   Connection c = DriverManager.getConnection(
                          "jdbc:sqlserver://localhost:1433;databaseName=Catalog", "user", "pass");

Driver: sqljdbc.jar

 MySQL

        Class.forName("com.mysql.jdbc.Driver"); 
        Connection c = DriverManager.getConnection(
                               "jdbc:mysql://localhost/databaseName","user","pass");

Driver: mysql-connector-java.jar