Erro Open Swing

package br.com.controllers;

import br.com.frames.CadCliFr;
import br.com.vos.CadCliVO;
import java.sql.*;
import java.util.*;
import org.openswing.swing.mdi.client.MDIFrame;
import org.openswing.swing.message.receive.java.*;
import org.openswing.swing.message.send.java.FilterWhereClause;
import org.openswing.swing.table.client.GridController;
import org.openswing.swing.table.java.GridDataLocator;

public class CadCliController extends GridController implements GridDataLocator {

    private Connection conn = null;
    private CadCliFr grid = null;

    public CadCliController(Connection conn) {

        this.conn = conn;
        grid = new CadCliFr(conn, this);
        
        /* FAZER UMA VERIFICAÇÃO
         * PARA NÃO DEIXAR ABRIR O MESMO
         * FORM MAIS DE UMA VEZ
        */

        MDIFrame.add(grid, true);
    }

    @Override
    public Response loadData(
            int action,
            int startIndex,
            Map filteredColumns,
            ArrayList currentSortedColumns,
            ArrayList currentSortedVersusColumns,
            Class valueObjectType,
            Map otherGridParams) {

        PreparedStatement stmt = null;

        try {
            String sql = "SELECT c.auto, "
                            + "  c.razao_social, "
                            + "  c.cpf_cnpj, "
                            + "  c.tel_cont1, "
                            + "  c.tel_cont2, "
                            + "  c.tel_cont3, "
                            + "  c.nome_fantasia, "
                            + "  c.cep, "
                            + "  c.tipo_logradouro, "
                            + "  c.logradouro, "
                            + "  c.complemento, "
                            + "  c.bairro, "
                            + "  c.cidade, "
                            + "  c.email1, "
                            + "  c.email2, "
                            + "  c.email3, "
                            + "  c.insc_estadual_rg, "
                            + "  c.insc_municipal, "
                            + "  c.observacao, "
                            + "  c.uf "

                            + "  FROM cliente c ;";

            Vector vals = new Vector();

            Map mapa = new HashMap();

            mapa.put("auto", "c.auto");
            mapa.put("razao_social", "c.razao_social");
            mapa.put("cpf_cnpj", "c.cpf_cnpj");
            mapa.put("tel_cont1", "c.tel_cont1");
            mapa.put("tel_cont2", "c.tel_cont2");
            mapa.put("tel_cont3", "c.tel_cont3");
            mapa.put("nome_fantasia", "c.nome_fantasia");
            mapa.put("cep", "c.cep");
            mapa.put("tipo_logradouro", "c.tipo_logradouro");
            mapa.put("logradouro", "c.logradouro");
            mapa.put("complemento", "c.complemento");
            mapa.put("bairro", "c.bairro");
            mapa.put("cidade", "c.cidade");
            mapa.put("email1", "c.email1");
            mapa.put("email2", "c.email2");
            mapa.put("email3", "c.email3");
            mapa.put("insc_estadual_rg", "c.insc_estadual_rg");
            mapa.put("insc_municipal", "c.insc_municipal");
            mapa.put("observacao", "c.observacao");
            mapa.put("uf", "c.uf");

            if (filteredColumns.size() > 0) {
                FilterWhereClause[] filter = (FilterWhereClause[]) filteredColumns.get("razao_social");
                sql += " WHERE c.razao_social " + filter[0].getOperator() + "?";
                vals.add(filter[0].getValue());
                /* if (filter[1] != null) {
                sql += " and DEMO2.TEXT " + filter[1].getOperator() + "?";
                vals.add(filter[1].getValue());
                }*/
                vals.add(filter[0].getValue());
            }
            if (currentSortedColumns.size() > 0) {
                sql += " ORDER BY " + mapa.get(currentSortedColumns.get(0).toString() + " " + currentSortedVersusColumns.get(0));
            }

            stmt = conn.prepareStatement(sql);

            for (int i = 0; i < vals.size(); i++) {
                stmt.setObject(i + 1, vals.get(i));
            }

            ResultSet rset = stmt.executeQuery();

            // imprime o result set
            System.out.println(rset);

            ArrayList list = new ArrayList();
            CadCliVO vo = null;
            while (rset.next()) {

                vo = new CadCliVO();

                // SETA O CAMPO AUTO DE CLIENRTE VO

                vo.setAuto(rset.getInt(1));
                
                vo.setRazao_social(rset.getString(2));
                vo.setCpf_cnpj(rset.getString(3));
                vo.setTel_cont1(rset.getString(4));
                vo.setTel_cont2(rset.getString(5));
                vo.setTel_cont3(rset.getString(6));
                vo.setNome_fantasia(rset.getString(7));
                vo.setCep(rset.getString(8));

                vo.setTipo_logradouro(rset.getInt(9));

                vo.setLogradouro(rset.getString(10));
                vo.setComplemento(rset.getString(11));
                vo.setBairro(rset.getString(12));
                vo.setCidade(rset.getString(13));

                vo.setEmail1(rset.getString(14));
                vo.setEmail2(rset.getString(15));
                vo.setEmail3(rset.getString(16));
                vo.setInsc_estadual_rg(rset.getString(17));
                vo.setInsc_municipal(rset.getString(18));
                vo.setObservacao(rset.getString(19));

                vo.setUf(rset.getInt(20));

                list.add(vo);
            }
            return new VOListResponse(list, false, list.size());
        } catch (SQLException ex) {
            return new ErrorResponse(ex.getMessage());
        } finally {
            try {
                stmt.close();
            } catch (SQLException ex1) {
                System.out.print("Erro: " + ex1);
            }
        }

    }

// apagar o registro
    public Response deleteRecord(ArrayList persistentObjects) throws Exception {

        PreparedStatement stmt = null;


        try {

            stmt = conn.prepareStatement("delete from CLIENTE where auto=?");

            for (int i = 0; i < persistentObjects.size(); i++) {

                CadCliVO vo = (CadCliVO) persistentObjects.get(i);
                stmt.setString(1, vo.getAuto().toString());
                stmt.execute();

            }
            return new VOResponse(true);

        } catch (SQLException ex) {
            return new ErrorResponse(ex.getMessage());
        } finally {
            try {
                stmt.close();
                conn.commit();
            } catch (SQLException ex1) {
            }
        }
    }
}