Textfield Hilfe in Java

package Secure;
import java.awt.HeadlessException;
import java.sql.*;
import javax.swing.*;
public class NewJFrame extends javax.swing.JFrame {
Connection conn=null;
PreparedStatement pst=null;
ResultSet rs=null;
    public NewJFrame() {
        initComponents();
    }


    /**
     * This method is called from within the constructor to initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is always
     * regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
    private void initComponents() {


        jLabel7 = new javax.swing.JLabel();
        jButton19 = new javax.swing.JButton();
        txtusername = new javax.swing.JTextField();
        txtpassword = new javax.swing.JTextField();


        jLabel7.setIcon(new javax.swing.ImageIcon("C:\\Users\\Hauptrechner\\Desktop\\datwe\\DRB\\Hintergrund_1.jpg")); // NOI18N
        jLabel7.setText("jLabel7");


        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
        setAlwaysOnTop(true);
        setBackground(new java.awt.Color(255, 102, 153));
        setFocusableWindowState(false);
        setFont(new java.awt.Font("Adobe Fan Heiti Std B", 0, 10)); // NOI18N
        setForeground(new java.awt.Color(255, 102, 102));
        setLocation(new java.awt.Point(800, 600));
        setLocationByPlatform(true);
        setMaximizedBounds(new java.awt.Rectangle(0, 0, 800, 600));
        setMinimumSize(new java.awt.Dimension(800, 600));
        setSize(new java.awt.Dimension(800, 600));


        jButton19.setText("Anmelden");
        jButton19.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton19ActionPerformed(evt);
            }
        });


        txtusername.setText("jTextField1");
        txtusername.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                txtusernameActionPerformed(evt);
            }
        });


        txtpassword.setText("jTextField1");
        txtpassword.addKeyListener(new java.awt.event.KeyAdapter() {
            public void keyPressed(java.awt.event.KeyEvent evt) {
                txtpasswordKeyPressed(evt);
            }
        });


        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGap(68, 68, 68)
                .addComponent(jButton19)
                .addContainerGap(653, Short.MAX_VALUE))
            .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING)
                    .addComponent(txtpassword, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(txtusername, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addGap(350, 350, 350))
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                .addGap(85, 85, 85)
                .addComponent(txtusername, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                .addComponent(txtpassword, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 430, Short.MAX_VALUE)
                .addComponent(jButton19)
                .addContainerGap())
        );


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


    private void jButton19ActionPerformed(java.awt.event.ActionEvent evt) {                                          
        conn =MySqlConnect.ConnectDB();
        String Sql="SELECT * FROM login where username=? and password=?";
        try{
            pst=conn.prepareStatement(Sql);
            pst.setString(1,txtusername.getText());
            pst.setString(2,txtpassword.getText());
            rs=pst.executeQuery();
            if(rs.next()){


                uebersicht w=new uebersicht();
                w.setVisible(true);
            }
            else{
                JOptionPane.showMessageDialog(null,"Falsche Daten.","Access Denied",JOptionPane.ERROR_MESSAGE);
            }
        } catch(HeadlessException | SQLException e) {
            JOptionPane.showMessageDialog(null,e);
        }


    }                                         


    private void txtusernameActionPerformed(java.awt.event.ActionEvent evt) {                                            

    }                                           


    private void txtpasswordKeyPressed(java.awt.event.KeyEvent evt) {                                       
        // TODO add your handling code here:
    }                                      


    /**
     * @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(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        //</editor-fold>


        /* Create and display the form */
        java.awt.EventQueue.invokeLater(() -> {
            new NewJFrame().setVisible(true);
        });
    }


    // Variables declaration - do not modify                     
    private javax.swing.JButton jButton19;
    private javax.swing.JLabel jLabel7;
    private javax.swing.JTextField txtpassword;
    private javax.swing.JTextField txtusername;
    // End of variables declaration                   
}