Erro

package cadastro;

/**
 *
 * @author  
 */


import java.sql.SQLException;
import java.util.Date;
import javax.swing.JOptionPane;
import javax.swing.JTable;
import javax.swing.table.DefaultTableModel;
import utilitarios.conexao;
public class Jtablevenas extends javax.swing.JFrame {
    
    /** Creates new form Jtablevendass */
    public Jtablevenas() {
        initComponents();
        
        conecta_vendas=new conexao();
        conecta_vendas.conecta();
        
        conecta_vendas.executaSQL("select * from TB_vendas order by "+ordenacao);
        preencher_jTableve();
        
    }
    
    Date data=new Date();
    
    conexao conecta_vendas;//,conecta_item;
    String ordenacao="id_venda";
    
    
    
    public void preencher_jTableve()
{
        
        
        jTable1.getColumnModel().getColumn(0).setPreferredWidth(20);
        jTable1.getColumnModel().getColumn(1).setPreferredWidth(20);
        jTable1.getColumnModel().getColumn(2).setPreferredWidth(100);
        jTable1.getColumnModel().getColumn(3).setPreferredWidth(100);
        jTable1.getColumnModel().getColumn(4).setPreferredWidth(50);
        jTable1.getColumnModel().getColumn(5).setPreferredWidth(100);
        jTable1.getColumnModel().getColumn(6).setPreferredWidth(100);
        jTable1.getColumnModel().getColumn(7).setPreferredWidth(100);
        jTable1.getColumnModel().getColumn(8).setPreferredWidth(100);
        jTable1.getColumnModel().getColumn(9).setPreferredWidth(100);
        jTable1.getColumnModel().getColumn(10).setPreferredWidth(100);
    
        DefaultTableModel modelo=(DefaultTableModel)jTable1.getModel();
        modelo.setNumRows(0);
        
        
        try
{
            
            while(conecta_vendas.resultset.next())
                modelo.addRow(new Object[]{
                    conecta_vendas.resultset.getString("id_venda"),
                    conecta_vendas.resultset.getString("codop"),
                    conecta_vendas.resultset.getString("dataatual"),
                    conecta_vendas.resultset.getDate("data_recebe"),
                    conecta_vendas.resultset.getString("praz"),
                    conecta_vendas.resultset.getString("formapag"),
                    conecta_vendas.resultset.getString("op"),
                    conecta_vendas.resultset.getString("taxautil"),
                    conecta_vendas.resultset.getDate("valorbruto"),
                    conecta_vendas.resultset.getString("valoliq"),
                    conecta_vendas.resultset.getString("obs"),
                    
                });
            
            conecta_vendas.resultset.first();//volta ao primeiro registro
        }
catch(SQLException erro)
{
    JOptionPane.showMessageDialog(null,"Erro,ao listar"+erro);
}
        
        
    }
    
    /** 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.
     */
    // <editor-fold defaultstate="collapsed" desc=" Generated Code ">                          
    private void initComponents() {
        jScrollPane1 = new javax.swing.JScrollPane();
        jTable1 = new javax.swing.JTable();
        jPanel1 = new javax.swing.JPanel();
        jLabel1 = new javax.swing.JLabel();
        tf_pesqpar = new javax.swing.JTextField();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
        setTitle("Hist\u00f3rico de parcelas");
        jTable1.setModel(new javax.swing.table.DefaultTableModel(
            new Object [][] {
                {null, null, null, null, null, null, null, null, null, null, null},
                {null, null, null, null, null, null, null, null, null, null, null},
                {null, null, null, null, null, null, null, null, null, null, null},
                {null, null, null, null, null, null, null, null, null, null, null}
            },
            new String [] {
                "Cod/Vendda", "Cod/Op", "Data da Venda", "Data a Receber", "Prazo", "Forma Pag.", "Operadora", "Taxa", "Valor Venda", "Valor a Receber", "Obs"
            }
        ) {
            Class[] types = new Class [] {
                java.lang.String.class, java.lang.String.class, java.lang.String.class, java.lang.String.class, java.lang.String.class, java.lang.String.class, java.lang.String.class, java.lang.String.class, java.lang.String.class, java.lang.String.class, java.lang.String.class
            };

            public Class getColumnClass(int columnIndex) {
                return types [columnIndex];
            }
        });
        jScrollPane1.setViewportView(jTable1);

        jPanel1.setBackground(new java.awt.Color(102, 153, 255));
        jLabel1.setFont(new java.awt.Font("Tahoma", 0, 18));
        jLabel1.setIcon(new javax.swing.ImageIcon("C:\Estoque\imagens\parcelas.png"));
        jLabel1.setText("Hist\u00f3rico de Parcelas");

        tf_pesqpar.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                tf_pesqparActionPerformed(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()
                .addComponent(jLabel1)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 246, Short.MAX_VALUE)
                .addComponent(tf_pesqpar, javax.swing.GroupLayout.PREFERRED_SIZE, 133, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addContainerGap())
        );
        jPanel1Layout.setVerticalGroup(
            jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(jPanel1Layout.createSequentialGroup()
                .addContainerGap()
                .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(jLabel1)
                    .addComponent(tf_pesqpar, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addContainerGap(22, Short.MAX_VALUE))
        );

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addComponent(jPanel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
            .addGroup(layout.createSequentialGroup()
                .addContainerGap()
                .addComponent(jScrollPane1, javax.swing.GroupLayout.DEFAULT_SIZE, 593, Short.MAX_VALUE)
                .addContainerGap())
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(jScrollPane1, javax.swing.GroupLayout.DEFAULT_SIZE, 302, Short.MAX_VALUE))
        );
        pack();
    }// </editor-fold>                        
    
    private void tf_pesqparActionPerformed(java.awt.event.ActionEvent evt) {                                           
        // conecta_vendas.executaSQL("select * from TB_recebe where nome like '%"+tf_pesqpar.getText()+"%'  order by "+oi);
    }                                          
    
    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new Jtablevenas().setVisible(true);
            }
        });
    }