How to Make JDBC Connection With SQL Server Express 2005 [on hold]

Help me to solve my issue

my code is

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

public class PrintFileToPrinter{

public static void main(String[] args){
    try{
    Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
    String dbURL = " jdbc:sqlserver://TOSHIBA-PC/SQLEXPRESS:1433;databaseName=COSEC;user=sa;password=22484;";
    Connection conn = DriverManager.getConnection(dbURL);
    if (conn != null) {
        System.out.println("Connected");
    }
    }catch(ClassNotFoundException | SQLException exception){
        exception.printStackTrace();
    }

}

}

and the error showing is

java.sql.SQLException: No suitable driver found for  jdbc:sqlserver://TOSHIBA-PC/SQLEXPRESS:1433;databaseName=COSEC;user=sa;password=22484;
at java.sql.DriverManager.getConnection(DriverManager.java:596)
at java.sql.DriverManager.getConnection(DriverManager.java:596)
at java.sql.DriverManager.getConnection(DriverManager.java:233)
at textfilemaker.PrintFileToPrinter.main(PrintFileToPrinter.java:19)

i am using sqljdbc4-2.0.jar my IDE is netbeans.

please help me in this issue and thanks in advance