import java.awt.*
import javax.swing.*
import java.awt.event.*
import java.sql.*
class LoginFrm extends JFrame implements ActionListener// throws Exception
{
JLabel lbl1 = new JLabel("用户名:")
JLabel lbl2 = new JLabel("密码:")
JTextField txt = new JTextField(5)
JPasswordField pf = new JPasswordField()
JButton btn1 = new JButton("确定")
JButton btn2 = new JButton("取消")
public LoginFrm() {
this.setTitle("登陆")
JPanel jp = (JPanel) this.getContentPane()
jp.setLayout(new GridLayout(3, 2, 5, 5))
jp.add(lbl1)
jp.add(txt)
jp.add(lbl2)
jp.add(pf)
jp.add(btn1)
jp.add(btn2)
btn1.addActionListener(this)
btn2.addActionListener(this)
}
public void actionPerformed(ActionEvent ae) {
if (ae.getSource() == btn1) {
try {
Class.forName("com.mysql.jdbc.Driver")// mysql数据库
Connection con = DriverManager.getConnection(
"jdbc:mysql://localhost/Car_zl", "root", "1")// 数据库名为Car_zl，密码为1
System.out.println("com : "+ con)
Statement cmd = con.createStatement()
String sql = "select * from user where User_ID='"
+ txt.getText() + "' and User_ps='"
+ pf.getText() + "'"
ResultSet rs = cmd
.executeQuery(sql)// 表名为user，user_ID和User_ps是存放用户名和密码的字段名
if (rs.next()) {
JOptionPane.showMessageDialog(null, "登陆成功！")
} else
JOptionPane.showMessageDialog(null, "用户名或密码错误！")
} catch (Exception ex) {
}
if (ae.getSource() == btn2) {
System.out.println("1111111111111")
//txt.setText("")
//pf.setText("")
System.exit(0)
}
}
}
public static void main(String arg[]) {
JFrame.setDefaultLookAndFeelDecorated(true)
LoginFrm frm = new LoginFrm()
frm.setSize(400, 200)
frm.setVisible(true)
}
}
1、首先用户注册完成后，返回一个boolean值的变量；
2、利用Servlet类判断这个变量，如果为true，跳转到提示界面，提示用户注册成功，如果为false，跳转到提示界面，提示用户注册失败；
3、具体代码如下所示：
public class DemoServlet extends HttpServlet {public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String username = request.getParameter("username")
String usepwd= request.getParameter("usepwd")
boolean flag = Dao.register(username,usepwd)//注册方法
if(flag){
//提示注册成功
request.getRequestDispatcher("/success.jsp").forward(request, response)
}else{
//提示注册失败
request.getRequestDispatcher("/success.jsp").forward(request, response)
}
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response)
}
}
4、至此，就完成了提示注册成功的功能。
