Java Netbeans登录表单错误

我在使用netbeans和SQLServerManagementStudio的java登录表单时遇到问题。与数据库的连接似乎没有问题，但当我单击“登录”按钮时，仍然没有发生任何事情，我猜我的代码中缺少了什么或有错误。 请帮忙

package sdbs;


import java.sql.*;
import javax.swing.JOptionPane;

public class Login extends javax.swing.JFrame {
Connection con;
PreparedStatement st;
ResultSet rs;

public Login() 
{
    initComponents();
}

@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">                          
private void initComponents() {

    jPanel1 = new javax.swing.JPanel();
    jLabel1 = new javax.swing.JLabel();
    jLabel2 = new javax.swing.JLabel();
    jTextField1 = new javax.swing.JTextField();
    jTextField2 = new javax.swing.JTextField();
    jButton1 = new javax.swing.JButton();
    jButton2 = new javax.swing.JButton();
    jButton3 = new javax.swing.JButton();
    jLabel3 = new javax.swing.JLabel();
    jLabel4 = new javax.swing.JLabel();

    setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

    jLabel1.setText("User");

    jLabel2.setText("Password");

    jButton1.setText("Submit");
    jButton1.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            jButton1ActionPerformed(evt);
        }
    });

    jButton2.setText("Change Password");
    jButton2.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            jButton2ActionPerformed(evt);
        }
    });

    jButton3.setText("Cancel");
    jButton3.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            jButton3ActionPerformed(evt);
        }
    });

    javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
    jPanel1.setLayout(jPanel1Layout);
    jPanel1Layout.setHorizontalGroup(
        jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, jPanel1Layout.createSequentialGroup()
            .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
            .addComponent(jButton2, javax.swing.GroupLayout.PREFERRED_SIZE, 74, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addGap(180, 180, 180))
        .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, jPanel1Layout.createSequentialGroup()
            .addGap(112, 112, 112)
            .addComponent(jButton1)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 160, Short.MAX_VALUE)
            .addComponent(jButton3)
            .addGap(33, 33, 33))
        .addGroup(jPanel1Layout.createSequentialGroup()
            .addGap(136, 136, 136)
            .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                .addComponent(jLabel3, javax.swing.GroupLayout.PREFERRED_SIZE, 117, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addGroup(jPanel1Layout.createSequentialGroup()
                    .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING)
                        .addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 77, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addComponent(jLabel2, javax.swing.GroupLayout.PREFERRED_SIZE, 77, javax.swing.GroupLayout.PREFERRED_SIZE))
                    .addGap(7, 7, 7)
                    .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                        .addComponent(jTextField1, javax.swing.GroupLayout.PREFERRED_SIZE, 102, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addComponent(jTextField2, javax.swing.GroupLayout.PREFERRED_SIZE, 104, javax.swing.GroupLayout.PREFERRED_SIZE))))
            .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
        .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, jPanel1Layout.createSequentialGroup()
                .addContainerGap(277, Short.MAX_VALUE)
                .addComponent(jLabel4, javax.swing.GroupLayout.PREFERRED_SIZE, 117, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addGap(95, 95, 95)))
    );
    jPanel1Layout.setVerticalGroup(
        jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(jPanel1Layout.createSequentialGroup()
            .addGap(30, 30, 30)
            .addComponent(jLabel3, javax.swing.GroupLayout.PREFERRED_SIZE, 35, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addGap(18, 18, 18)
            .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                .addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 28, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addComponent(jTextField2, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
            .addGap(18, 18, 18)
            .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                .addComponent(jLabel2, javax.swing.GroupLayout.PREFERRED_SIZE, 28, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addComponent(jTextField1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
            .addGap(26, 26, 26)
            .addComponent(jButton2)
            .addGap(18, 18, 18)
            .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                .addComponent(jButton3)
                .addComponent(jButton1))
            .addContainerGap(53, Short.MAX_VALUE))
        .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(jPanel1Layout.createSequentialGroup()
                .addGap(52, 52, 52)
                .addComponent(jLabel4, javax.swing.GroupLayout.PREFERRED_SIZE, 35, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addContainerGap(213, Short.MAX_VALUE)))
    );

    javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
    getContentPane().setLayout(layout);
    layout.setHorizontalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addContainerGap()
            .addComponent(jPanel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
    );
    layout.setVerticalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addComponent(jPanel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
    );

    pack();
}// </editor-fold>                        

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) 
{                                         
    // TODO add your handling code here:
    String uname= jTextField1.getText();
    String pass= jTextField2.getText();
    String dbname="0";
    String dbpass="0";

    try
    {
        Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");  
        //DriverManager.registerDriver(new com.microsoft.sqlserver.jdbc.SQLServerDriver());  
        String url = "jdbc:sqlserver://AMISH-PC:1433;databaseName=Student;user=sa;password=comprishu"; 
        Connection con = DriverManager.getConnection(url);
        System.out.println("Database Conneeted");
        String sqlquery="select * from Login where User=? and Password=?";
        st=con.prepareStatement(sqlquery);
        rs=st.executeQuery();
        if(rs.next())
        {
            dbname=rs.getString("User");
            dbpass=rs.getString("Password");
        }
    }
    catch(  ClassNotFoundException cnfe)
    {
        JOptionPane.showMessageDialog(null,"Class.forName Error Msg");
        cnfe.printStackTrace();
    }      
    catch(SQLException sqle)
    {
        JOptionPane.showMessageDialog(null,"SQL Error Msg");
        sqle.printStackTrace();
        return;
    }

    if(uname.equals(dbname) && pass.equals(dbpass))
    {
        Home a=new Home();
        a.setVisible(true);
    }

    else if(uname.equals("") || pass.equals(""))
    {
       JOptionPane.showMessageDialog(null,"Enter Valid Name & Password..!");
    }
}                                        

private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {                                         
    // TODO add your handling code here:
    new ChangePassword().setVisible(true);
}                                        

private void jButton3ActionPerformed(java.awt.event.ActionEvent evt) {                                         
    // TODO add your handling code here:
    System.exit(0);
    System.exit(0);
}                                        

/**
 * @param args the command line arguments
 */
public static void main(String args[]) {
    /* Set the Nimbus look and feel */
    //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
    /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
     * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html 
     */
    try {
        for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
            if ("Nimbus".equals(info.getName())) {
                javax.swing.UIManager.setLookAndFeel(info.getClassName());
                break;
            }
        }
    } catch (ClassNotFoundException ex) {
        java.util.logging.Logger.getLogger(Login.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (InstantiationException ex) {
        java.util.logging.Logger.getLogger(Login.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (IllegalAccessException ex) {
        java.util.logging.Logger.getLogger(Login.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (javax.swing.UnsupportedLookAndFeelException ex) {
        java.util.logging.Logger.getLogger(Login.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    }
    //</editor-fold>

    /* Create and display the form */
    java.awt.EventQueue.invokeLater(new Runnable() {
        public void run() {
            new Login().setVisible(true);
        }
    });
}

// Variables declaration - do not modify                     
private javax.swing.JButton jButton1;
private javax.swing.JButton jButton2;
private javax.swing.JButton jButton3;
private javax.swing.JLabel jLabel1;
private javax.swing.JLabel jLabel2;
private javax.swing.JLabel jLabel3;
private javax.swing.JLabel jLabel4;
private javax.swing.JPanel jPanel1;
private javax.swing.JTextField jTextField1;
private javax.swing.JTextField jTextField2;
// End of variables declaration                   
}

---

}

你有日志吗？什么是家？当您执行a.setVisible（true）时，您希望发生什么；？Home是新的框架&编写代码“a.setVisible（true）”是为了使Home框架可见。这不会发生……拥有两个框架是完全错误的。看看JDialog。CardLayout也不错。好的。假设我必须在正确验证用户和密码后点击sumbit按钮打开新表单。在netbeans中是如何做到的？

import java.sql.*;
import java.io.*;

public class databsechk
{
public static void main(String[] args) 
{
  try
  {
        Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");  
         String url =  "jdbc:sqlserver://AMISHPC:1433;databaseName=Student;user=sa;password=comprishu"; 
        Connection con = DriverManager.getConnection(url);
        System.out.println("Database Connected");
        Statement st = con.createStatement();
        ResultSet rs = st.executeQuery("Select * from Login ");
        while(rs.next())
        {
            System.out.println(rs.getString(1));
            System.out.println(rs.getString(2));
        }
   }
    catch(SQLException e)
     {
      System.out.println("Error in getting connection") ; 
     }
  catch(  ClassNotFoundException cnfe)
    {
        System.out.println("Error in getting finding class"); 
    }
}