Duvida Dao

import java.io.*;
import java.sql.*;
import java.util.*;
import java.math.*;
public class Cliente implements Cloneable, Serializable {

    private String codigo;
    private String nome;
    private String tipo;

    public Cliente () {

    }

    public Cliente (String codigoIn) {

          this.codigo = codigoIn;

    }

    /** 
     * Get- and Set-methods for persistent variables. 
     */

    public String getCodigo() {
          return this.codigo;
    }
    public void setCodigo(String codigoIn) {
          this.codigo = codigoIn;
    }

    public String getNome() {
          return this.nome;
    }
    public void setNome(String nomeIn) {
          this.nome = nomeIn;
    }

    public String getTipo() {
          return this.tipo;
    }
    public void setTipo(String tipoIn) {
          this.tipo = tipoIn;
    }
    /** 
     * setAll allows to set all persistent variables in one method call.
    */

    public void setAll(String codigoIn,
          String nomeIn,
          String tipoIn) {
          this.codigo = codigoIn;
          this.nome = nomeIn;
          this.tipo = tipoIn;
    }
    /** 
     * hasEqualMapping-method will compare two Cliente instances
     * and return true if they contain same values in all persistent instance 
     * variables. 
     */
    public boolean hasEqualMapping(Cliente valueObject) {

          if (this.codigo == null) {
                    if (valueObject.getCodigo() != null)
                           return(false);
          } else if (!this.codigo.equals(valueObject.getCodigo())) {
                    return(false);
          }
          if (this.nome == null) {
                    if (valueObject.getNome() != null)
                           return(false);
          } else if (!this.nome.equals(valueObject.getNome())) {
                    return(false);
          }
          if (this.tipo == null) {
                    if (valueObject.getTipo() != null)
                           return(false);
          } else if (!this.tipo.equals(valueObject.getTipo())) {
                    return(false);
          }

          return true;
    }
    public String toString() {
        StringBuffer out = new StringBuffer(this.getDaogenVersion());
        out.append("\nclass Cliente, mapping to table Cliente\n");
        out.append("Persistent attributes: \n"); 
        out.append("codigo = " + this.codigo + "\n"); 
        out.append("nome = " + this.nome + "\n"); 
        out.append("tipo = " + this.tipo + "\n"); 
        return out.toString();
    }
    /**
     * Clone will return identical deep copy of this valueObject.
     */
    public Object clone() {
        Cliente cloned = new Cliente();
        if (this.codigo != null)
             cloned.setCodigo(new String(this.codigo)); 
        if (this.nome != null)
             cloned.setNome(new String(this.nome)); 
        if (this.tipo != null)
             cloned.setTipo(new String(this.tipo)); 
        return cloned;
    }
}
// ClienteDao
import java.sql.*;
import java.util.*;
import java.math.*;

public class ClienteDao {
    public Cliente createValueObject() {
          return new Cliente();
    }
    public Cliente getObject(Connection conn, String codigo) throws NotFoundException, SQLException {

          Cliente valueObject = createValueObject();
          valueObject.setCodigo(codigo);
          load(conn, valueObject);
          return valueObject;
    }
    public void load(Connection conn, Cliente valueObject) throws NotFoundException, SQLException {

          if (valueObject.getCodigo() == null) {
               //System.out.println("Can not select without Primary-Key!");
               throw new NotFoundException("Can not select without Primary-Key!");
          }

          String sql = "SELECT * FROM Cliente WHERE (codigo = ? ) "; 
          PreparedStatement stmt = null;

          try {
               stmt = conn.prepareStatement(sql);
               stmt.setString(1, valueObject.getCodigo()); 

               singleQuery(conn, stmt, valueObject);

          } finally {
              if (stmt != null)
                  stmt.close();
          }
    }
    public List loadAll(Connection conn) throws SQLException {

          String sql = "SELECT * FROM Cliente ORDER BY codigo ASC ";
          List searchResults = listQuery(conn, conn.prepareStatement(sql));

          return searchResults;
    }
    public synchronized void create(Connection conn, Cliente valueObject) throws SQLException {

          String sql = "";
          PreparedStatement stmt = null;
          ResultSet result = null;

          try {
               sql = "INSERT INTO Cliente ( codigo, nome, tipo) VALUES (?, ?, ?) ";
               stmt = conn.prepareStatement(sql);

               stmt.setString(1, valueObject.getCodigo()); 
               stmt.setString(2, valueObject.getNome()); 
               stmt.setString(3, valueObject.getTipo()); 

               int rowcount = databaseUpdate(conn, stmt);
               if (rowcount != 1) {
                    //System.out.println("PrimaryKey Error when updating DB!");
                    throw new SQLException("PrimaryKey Error when updating DB!");
               }

          } finally {
              if (stmt != null)
                  stmt.close();
          }
    }
      public void save(Connection conn, Cliente valueObject) 
          throws NotFoundException, SQLException {

          String sql = "UPDATE Cliente SET nome = ?, tipo = ? WHERE (codigo = ? ) ";
          PreparedStatement stmt = null;

          try {
              stmt = conn.prepareStatement(sql);
              stmt.setString(1, valueObject.getNome()); 
              stmt.setString(2, valueObject.getTipo()); 

              stmt.setString(3, valueObject.getCodigo()); 

              int rowcount = databaseUpdate(conn, stmt);
              if (rowcount == 0) {
                   //System.out.println("Object could not be saved! (PrimaryKey not found)");
                   throw new NotFoundException("Object could not be saved! (PrimaryKey not found)");
              }
              if (rowcount > 1) {
                   //System.out.println("PrimaryKey Error when updating DB! (Many objects were affected!)");
                   throw new SQLException("PrimaryKey Error when updating DB! (Many objects were affected!)");
              }
          } finally {
              if (stmt != null)
                  stmt.close();
          }
    }
    public void delete(Connection conn, Cliente valueObject) 
          throws NotFoundException, SQLException {

          if (valueObject.getCodigo() == null) {
               //System.out.println("Can not delete without Primary-Key!");
               throw new NotFoundException("Can not delete without Primary-Key!");
          }

          String sql = "DELETE FROM Cliente WHERE (codigo = ? ) ";
          PreparedStatement stmt = null;

          try {
              stmt = conn.prepareStatement(sql);
              stmt.setString(1, valueObject.getCodigo()); 

              int rowcount = databaseUpdate(conn, stmt);
              if (rowcount == 0) {
                   //System.out.println("Object could not be deleted (PrimaryKey not found)");
                   throw new NotFoundException("Object could not be deleted! (PrimaryKey not found)");
              }
              if (rowcount > 1) {
                   //System.out.println("PrimaryKey Error when updating DB! (Many objects were deleted!)");
                   throw new SQLException("PrimaryKey Error when updating DB! (Many objects were deleted!)");
              }
          } finally {
              if (stmt != null)
                  stmt.close();
          }
    }

    public void deleteAll(Connection conn) throws SQLException {

          String sql = "DELETE FROM Cliente";
          PreparedStatement stmt = null;

          try {
              stmt = conn.prepareStatement(sql);
              int rowcount = databaseUpdate(conn, stmt);
          } finally {
              if (stmt != null)
                  stmt.close();
          }
    }
    public int countAll(Connection conn) throws SQLException {

          String sql = "SELECT count(*) FROM Cliente";
          PreparedStatement stmt = null;
          ResultSet result = null;
          int allRows = 0;

          try {
              stmt = conn.prepareStatement(sql);
              result = stmt.executeQuery();

              if (result.next())
                  allRows = result.getInt(1);
          } finally {
              if (result != null)
                  result.close();
              if (stmt != null)
                  stmt.close();
          }
          return allRows;
    }

    public List searchMatching(Connection conn, Cliente valueObject) throws SQLException {

          List searchResults;

          boolean first = true;
          StringBuffer sql = new StringBuffer("SELECT * FROM Cliente WHERE 1=1 ");

          if (valueObject.getCodigo() != null) {
              if (first) { first = false; }
              sql.append("AND codigo LIKE '").append(valueObject.getCodigo()).append("%' ");
          }

          if (valueObject.getNome() != null) {
              if (first) { first = false; }
              sql.append("AND nome LIKE '").append(valueObject.getNome()).append("%' ");
          }

          if (valueObject.getTipo() != null) {
              if (first) { first = false; }
              sql.append("AND tipo LIKE '").append(valueObject.getTipo()).append("%' ");
          }


          sql.append("ORDER BY codigo ASC ");

          // Prevent accidential full table results.
          // Use loadAll if all rows must be returned.
          if (first)
               searchResults = new ArrayList();
          else
               searchResults = listQuery(conn, conn.prepareStatement(sql.toString()));

          return searchResults;
    }

        public String getDaogenVersion() {
        return "DaoGen version 2.4.1";
    }

    protected int databaseUpdate(Connection conn, PreparedStatement stmt) throws SQLException {

          int result = stmt.executeUpdate();

          return result;
    }
    protected void singleQuery(Connection conn, PreparedStatement stmt, Cliente valueObject) 
          throws NotFoundException, SQLException {

          ResultSet result = null;

          try {
              result = stmt.executeQuery();

              if (result.next()) {

                   valueObject.setCodigo(result.getString("codigo")); 
                   valueObject.setNome(result.getString("nome")); 
                   valueObject.setTipo(result.getString("tipo")); 

              } else {
                    //System.out.println("Cliente Object Not Found!");
                    throw new NotFoundException("Cliente Object Not Found!");
              }
          } finally {
              if (result != null)
                  result.close();
              if (stmt != null)
                  stmt.close();
          }
    }
    protected List listQuery(Connection conn, PreparedStatement stmt) throws SQLException {

          ArrayList searchResults = new ArrayList();
          ResultSet result = null;

          try {
              result = stmt.executeQuery();

              while (result.next()) {
                   Cliente temp = createValueObject();

                   temp.setCodigo(result.getString("codigo")); 
                   temp.setNome(result.getString("nome")); 
                   temp.setTipo(result.getString("tipo")); 

                   searchResults.add(temp);
              }

          } finally {
              if (result != null)
                  result.close();
              if (stmt != null)
                  stmt.close();
          }

          return (List)searchResults;
    }

}