Exception in thread "AWT-EventQueue-0" java.lang.StackOverflowError

Programação Java
,
#1

Galera, eu tô fazendo um trabalho da faculdade e eu tô com os seguintes erros na tela de efetuar venda:

Exception in thread “AWT-EventQueue-0” java.lang.StackOverflowError
at java.security.AccessController.doPrivileged(Native Method)
at sun.awt.SunToolkit.getSunAwtNoerasebackground(SunToolkit.java:706)
at sun.awt.windows.WCanvasPeer.initialize(WCanvasPeer.java:53)
at sun.awt.windows.WPanelPeer.initialize(WPanelPeer.java:79)
at sun.awt.windows.WWindowPeer.initialize(WWindowPeer.java:176)
at sun.awt.windows.WFramePeer.initialize(WFramePeer.java:200)
at sun.awt.windows.WComponentPeer.(WComponentPeer.java:796)
at sun.awt.windows.WCanvasPeer.(WCanvasPeer.java:45)
at sun.awt.windows.WPanelPeer.(WPanelPeer.java:74)
at sun.awt.windows.WWindowPeer.(WWindowPeer.java:171)
at sun.awt.windows.WFramePeer.(WFramePeer.java:181)
at sun.awt.windows.WToolkit.createFrame(WToolkit.java:408)
at java.awt.Frame.addNotify(Frame.java:477)
at java.awt.Window.pack(Window.java:807)
at telasvendedor.Produto.initComponents(Produto.java:122)
at telasvendedor.Produto.(Produto.java:25)
at telasvendedor.Vender.(Vender.java:41)
at telasvendedor.Vender.(Vender.java:42)

Segue código da tela:

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package telasvendedor;

import bancodedados.Conectadb;
import controller.Controller;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.JOptionPane;
import javax.swing.JTable;
import javax.swing.table.DefaultTableModel;

/**
 *
 * @author Yanzão
 */
public class Vender extends javax.swing.JFrame {

    public static int codigoC;
    public static int vendaC;
    /**
     * Creates new form Vender
     */
    public Vender() throws SQLException {
        criaJTable();
        initComponents();
        jScrollPanel.setViewportView(tabela);
    }
    
    private JTable tabela;
    private DefaultTableModel modelo = new DefaultTableModel();
    private Connection con;
    Controller c = new Controller();
    Produto p = new Produto();
    Vender t = new Vender();
    
    private void criaJTable() throws SQLException {
        tabela = new JTable(modelo);
        modelo.addColumn("CódigoVenda");
        modelo.addColumn("CódigoProduto");
        modelo.addColumn("Quantidade");
        tabela.getColumnModel().getColumn(0).setPreferredWidth(30);
        tabela.getColumnModel().getColumn(1).setPreferredWidth(30);
        tabela.getColumnModel().getColumn(2).setPreferredWidth(30);
        pesquisarVendas("SELECT * FROM vendas");
    }
      
    private void pesquisarVendas(String sql) throws SQLException {
        modelo.setNumRows(0);
        Connection con =  Conectadb.getConnection();
        PreparedStatement preparedStatement = null;
        
        preparedStatement = con.prepareStatement(sql);
        ResultSet rs = preparedStatement.executeQuery();

        while (rs.next()) {
            modelo.addRow(new String [] {rs.getString("CodigoVenda"),rs.getString("CodigoProduto"),rs.getString("Quantidade")});
        }
               
    }

    /**
     * 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() {

        jPanel1 = new javax.swing.JPanel();
        jComboBox = new javax.swing.JComboBox<>();
        jLabel6 = new javax.swing.JLabel();
        jLabel2 = new javax.swing.JLabel();
        txtCodigoC = new javax.swing.JTextField();
        jButton1 = new javax.swing.JButton();
        jScrollPanel = new javax.swing.JScrollPane();
        jLabel3 = new javax.swing.JLabel();
        jLabel4 = new javax.swing.JLabel();
        txtTotal = new javax.swing.JLabel();
        jButton2 = new javax.swing.JButton();
        jButton3 = new javax.swing.JButton();
        jButton4 = new javax.swing.JButton();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

        jPanel1.setBorder(javax.swing.BorderFactory.createTitledBorder(null, "Vender", javax.swing.border.TitledBorder.CENTER, javax.swing.border.TitledBorder.DEFAULT_POSITION, new java.awt.Font("Tahoma", 1, 14))); // NOI18N

        jComboBox.setModel(new javax.swing.DefaultComboBoxModel<>(new String[] { "Selecione a forma de pagamento", "À vista", "A prazo" }));

        jLabel6.setText("Forma de pagamento");

        jLabel2.setText("Código cliente");

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

        jLabel3.setText("Total");

        jLabel4.setText("R$");

        jButton2.setText("Finalizar venda");

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

        jButton4.setText("Calcular desconto");
        jButton4.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton4ActionPerformed(evt);
            }
        });

        javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
        jPanel1.setLayout(jPanel1Layout);
        jPanel1Layout.setHorizontalGroup(
            jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(jPanel1Layout.createSequentialGroup()
                .addContainerGap()
                .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addComponent(jButton1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                    .addComponent(jScrollPanel)
                    .addGroup(jPanel1Layout.createSequentialGroup()
                        .addComponent(jLabel3)
                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                        .addComponent(jLabel4)
                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                        .addComponent(txtTotal, javax.swing.GroupLayout.PREFERRED_SIZE, 60, javax.swing.GroupLayout.PREFERRED_SIZE))
                    .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, jPanel1Layout.createSequentialGroup()
                        .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                            .addComponent(jLabel6)
                            .addComponent(jLabel2))
                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 69, Short.MAX_VALUE)
                        .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
                            .addComponent(txtCodigoC)
                            .addComponent(jComboBox, 0, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)))
                    .addComponent(jButton3, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                    .addComponent(jButton2, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                    .addComponent(jButton4, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
                .addContainerGap())
        );
        jPanel1Layout.setVerticalGroup(
            jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(jPanel1Layout.createSequentialGroup()
                .addContainerGap()
                .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
                    .addComponent(jComboBox)
                    .addComponent(jLabel6, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
                .addGap(18, 18, 18)
                .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
                    .addComponent(txtCodigoC)
                    .addComponent(jLabel2, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
                .addGap(18, 18, 18)
                .addComponent(jButton1)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(jScrollPanel, javax.swing.GroupLayout.PREFERRED_SIZE, 100, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addGap(18, 18, 18)
                .addComponent(jButton4)
                .addGap(18, 18, 18)
                .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addComponent(jLabel4)
                    .addComponent(txtTotal, javax.swing.GroupLayout.PREFERRED_SIZE, 14, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(jLabel3))
                .addGap(18, 18, 18)
                .addComponent(jButton2)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(jButton3)
                .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, 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.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
        );
        layout.setVerticalGroup(
            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)
                .addContainerGap())
        );

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

    private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         
        // TODO add your handling code here:        
        
        if (txtCodigoC.getText() == null || jComboBox.getSelectedItem() == "Selecione a forma de pagamento") {
            JOptionPane.showMessageDialog(null, "Há algum campo vazio, verifique e tente novamente!");
        } else {
            String venda = (String) jComboBox.getSelectedItem();
            codigoC = Integer.parseInt(txtCodigoC.getText());
            if ("À vista".equals(venda)) {
                vendaC = 1;
            } else if ("A prazo".equals(venda)) {
                vendaC = 2;
            }
            try {
                c.efetuarVenda(codigoC, Controller.matV, vendaC);
            } catch (SQLException ex) {
                Logger.getLogger(Vender.class.getName()).log(Level.SEVERE, null, ex);
            }
            new telasvendedor.Produto().setVisible(true);
            this.dispose();
        }
        
    }                                        

    private void jButton4ActionPerformed(java.awt.event.ActionEvent evt) {                                         
        // TODO add your handling code here:
        
        int codV = Controller.codigoV;
        
        if (c.verificarSegunda()) {
            int veri = Integer.parseInt(JOptionPane.showInputDialog("O produto é para criança? 1- SIM | 2- NÃO"));
            if (veri == 1) {
                Produto.total = c.descontoCrianca(Produto.total);
                JOptionPane.showMessageDialog(null, "Desconto de 5% dado para produto de criança na segunda!");
                String tot = Float.toString(Produto.total);
                txtTotal.setText(tot);
            } else {
                JOptionPane.showMessageDialog(null, "Nenhum desconto foi aplicado.");
                String tot = Float.toString(Produto.total);
                txtTotal.setText(tot);
            }
        } else try {
            if (c.verificarSabado() && c.calcularIdade(Vender.codigoC) && vendaC == 1) {
                Produto.total = c.descontoA(Produto.total);
                JOptionPane.showMessageDialog(null, "Desconto de 10% dado para cliente idoso no sábado!");
                String tot = Float.toString(Produto.total);
                txtTotal.setText(tot);
            } else if (c.verificarSabado() && c.calcularIdade(Vender.codigoC) && vendaC == 2) {
                int par = Integer.parseInt(JOptionPane.showInputDialog("Deseja parcelar em quantas vezes? 1x (DESCONTO 5%) | 2x (DESCONTO 5%) | 3x | 4x | 5x"));
                if (par == 1 || par == 2) {
                    Produto.total = c.descontoP(Produto.total);
                    String tot = Float.toString(Produto.total);
                    txtTotal.setText(tot);
                }
            } else {
                JOptionPane.showMessageDialog(null, "Nenhum desconto foi aplicado.");
                String tot = Float.toString(Produto.total);
                txtTotal.setText(tot);
            }
        } catch (SQLException ex) {
            Logger.getLogger(Produto.class.getName()).log(Level.SEVERE, null, ex);
        }
    }                                        

    private void jButton3ActionPerformed(java.awt.event.ActionEvent evt) {                                         
        // TODO add your handling code here:
        new trabalhopoointerface.TelaVendedor().setVisible(true);
        this.dispose();
    }                                        

    /**
     * @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(Vender.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(Vender.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(Vender.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(Vender.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() {
                try {
                    new Vender().setVisible(true);
                } catch (SQLException ex) {
                    Logger.getLogger(Vender.class.getName()).log(Level.SEVERE, null, ex);
                }
            }
        });
    }

    // Variables declaration - do not modify                     
    private javax.swing.JButton jButton1;
    private javax.swing.JButton jButton2;
    private javax.swing.JButton jButton3;
    private javax.swing.JButton jButton4;
    private javax.swing.JComboBox<String> jComboBox;
    private javax.swing.JLabel jLabel2;
    private javax.swing.JLabel jLabel3;
    private javax.swing.JLabel jLabel4;
    private javax.swing.JLabel jLabel6;
    private javax.swing.JPanel jPanel1;
    private javax.swing.JScrollPane jScrollPanel;
    private javax.swing.JTextField txtCodigoC;
    private javax.swing.JLabel txtTotal;
    // End of variables declaration                   
}

Tela vender e estrutura sql
Tela produto e estrutura sql

#2

Posta a classe Produto

#3

Faltou o fonte da classe Produto, que é onde está estourando a pilha.

#4 
public class Produto extends javax.swing.JFrame {

    public static float total;
    /**
     * Creates new form Produto
     */
    public Produto() {
        initComponents();
    }
    Controller c = new Controller();

    /**
     * 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() {

        jPanel1 = new javax.swing.JPanel();
        jLabel1 = new javax.swing.JLabel();
        jLabel2 = new javax.swing.JLabel();
        txtCodP = new javax.swing.JTextField();
        txtQuantidade = new javax.swing.JTextField();
        jButton1 = new javax.swing.JButton();
        jButton2 = new javax.swing.JButton();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

        jPanel1.setBorder(javax.swing.BorderFactory.createTitledBorder(null, "Adicionar produto ao carrinho", javax.swing.border.TitledBorder.CENTER, javax.swing.border.TitledBorder.DEFAULT_POSITION, new java.awt.Font("Tahoma", 1, 14))); // NOI18N

        jLabel1.setText("Código do produto");

        jLabel2.setText("Quantidade");

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

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

        javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
        jPanel1.setLayout(jPanel1Layout);
        jPanel1Layout.setHorizontalGroup(
            jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(jPanel1Layout.createSequentialGroup()
                .addContainerGap()
                .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addComponent(jButton1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                    .addGroup(jPanel1Layout.createSequentialGroup()
                        .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                            .addComponent(jLabel2)
                            .addComponent(jLabel1))
                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 89, Short.MAX_VALUE)
                        .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
                            .addComponent(txtQuantidade, javax.swing.GroupLayout.DEFAULT_SIZE, 60, Short.MAX_VALUE)
                            .addComponent(txtCodP)))
                    .addComponent(jButton2, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
                .addContainerGap())
        );
        jPanel1Layout.setVerticalGroup(
            jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(jPanel1Layout.createSequentialGroup()
                .addContainerGap()
                .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addComponent(jLabel1)
                    .addComponent(txtCodP, 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.LEADING)
                    .addComponent(jLabel2)
                    .addComponent(txtQuantidade, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addGap(18, 18, 18)
                .addComponent(jButton1)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(jButton2)
                .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, 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.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addContainerGap()
                .addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addContainerGap(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:
        float total = 0;
        float preco = 0;

        if (txtCodP.getText() == null || txtQuantidade.getText() == null) {
            JOptionPane.showMessageDialog(null, "Há algum campo vazio, verifique e tente novamente!");
        } else {           
            int codigoP = Integer.parseInt(txtCodP.getText());
            int quantidade = Integer.parseInt(txtQuantidade.getText());
            try {
                preco = c.obterValorP(codigoP);
            } catch (SQLException ex) {
                Logger.getLogger(Produto.class.getName()).log(Level.SEVERE, null, ex);
            }
            total = total + (preco * quantidade);
            int codV = Controller.codigoV;
            try {
                c.adicionarVendaP(codigoP, quantidade, Controller.codigoV);
            } catch (SQLException ex) {
                Logger.getLogger(Produto.class.getName()).log(Level.SEVERE, null, ex);
            }
            
            
            try {
                c.alterarTotal(total, Controller.codigoV);
            } catch (SQLException ex) {
                Logger.getLogger(Produto.class.getName()).log(Level.SEVERE, null, ex);
            }
            
        }

    }                                        

    private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {                                         
        try {
            // TODO add your handling code here:
            new telasvendedor.Vender().setVisible(true);
        } catch (SQLException ex) {
            Logger.getLogger(Produto.class.getName()).log(Level.SEVERE, null, ex);
        }
        this.dispose();
    }                                        

    /**
     * @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(Produto.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(Produto.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(Produto.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(Produto.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 Produto().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify                     
    private javax.swing.JButton jButton1;
    private javax.swing.JButton jButton2;
    private javax.swing.JLabel jLabel1;
    private javax.swing.JLabel jLabel2;
    private javax.swing.JPanel jPanel1;
    private javax.swing.JTextField txtCodP;
    private javax.swing.JTextField txtQuantidade;
    // End of variables declaration                   
}
#5

Na classe Vender você tem um atributo do tipo Vender que é inicializado quando você instancia a classe Vender.
Aí vai instanciar recursivamente objetos da classe Vender até estourar a pilha.

#6

Realmente kk.
Agora tá dando:
Exception in thread "AWT-EventQueue-0" java.lang.RuntimeException: java.sql.SQLException: Column 'CodigoVenda' not found.

Porém na tabela tem a coluna ‘CodigoVenda’.
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