以下是纯JDBC连接数据库的代码,但连接不到数据库,抛出异常java.sql.SQLException: No suitable driver

package jdbc_odbc;

import java.awt.*;
import javax.swing.*;
import java.awt.BorderLayout;
import com.borland.jbcl.layout.XYLayout;
import com.borland.jbcl.layout.*;
import javax.swing.table.DefaultTableModel;
import java.sql.*;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import java.util.Vector;

public class Frame_jbdc
extends JFrame {
public JButton jButton1 = new JButton();
public XYLayout xYLayout1 = new XYLayout();
public JScrollPane jScrollPane1 = new JScrollPane();
public JTable table = new JTable();
DefaultTableModel dt=new DefaultTableModel();
public Frame_jbdc() {
try {
jbInit();
}
catch (Exception exception) {
exception.printStackTrace();
}
}

private void jbInit() throws Exception {
getContentPane().setLayout(xYLayout1);
jButton1.setText("jButton1");
jButton1.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
jButton1_actionPerformed(e);
}
});
this.getContentPane().add(jButton1, new XYConstraints(18, 9, 100, 28));
this.getContentPane().add(jScrollPane1, new XYConstraints(44, 54, 313, 196));
jScrollPane1.getViewport().add(table);
dt.addColumn("电脑编号");
dt.addColumn("状态");
dt.addColumn("备注");
//createTableModel();
table.setModel(dt);

}

public void jButton1_actionPerformed(ActionEvent e) {
String url="jdbc:microsoft:sqlserver://";
String serverName="keni";
String portNumber="1434";
String databaseName="netbar";
try {
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
}
catch (ClassNotFoundException ex) {
ex.printStackTrace();
}
try {
Connection con = DriverManager.getConnection("jdbc:microsoft:sqlserver://keni:1433;databaseName=netbar;","sa","123");
Statement s = con.createStatement();
String strSel = "select * from Computer";
ResultSet rs = s.executeQuery(strSel);
if (table.getRowCount() > 0) {
for (int i = 0; table.getRowCount() > 0; i++) {
dt.removeRow(0);
}
}
while (rs.next()) {
Vector v=new Vector();
v.addElement(rs.getString(1));
v.addElement(rs.getString(2));
v.addElement(rs.getString(3));
dt.addRow(v);
}

rs.close();
s.close();
con.close();

}
catch (SQLException ex1) {
ex1.printStackTrace();
}
}
}