[enterprise-list] NullPointerException

darroio Fri, 18 Oct 2002 07:31:41 -0700

Bom dia !

Pessoal ! Segue abaixo o meu c�digo e estou com um problema ( Null Pointer Exception )..

Se algu�m puder ajudar.. Grato !

import java.util.Date;
import java.io.*;
import java.util.*;
import java.sql.*;
import javax.servlet.*;
import javax.servlet.http.*;

public class ServiceServlet extends HttpServlet
{
    private String usuario;
    private String senha;
    private String query;

    private static Connection connection = null;
    private static Statement statement = null;
    private static String url = " "jdbc:mysql://192.168.0.2/databov";    private static String driver = "org.gjt.mm.mysql.Driver";

    // Initializes the servlet.
    public void init( ServletConfig config ) throws ServletException
    {
        super.init( config );

        try
        {
            Class.forName( driver );
            connection = DriverManager.getConnection(url,"databov","cpbd1543k");
        }
        catch( Exception e )
        {
            e.printStackTrace();
            connection = null;
        }
    }

    public ResultSet executeQuery(String sql) throws SQLException
    {
        return statement.executeQuery(sql);
    }

    public void service(HttpServletRequest request, HttpServletResponse response)
               throws ServletException, java.io.IOException
    {

      response.setContentType("text/html");
        PrintWriter out = response.getWriter();

       // Permite fazer a cria��o do cookie
        String cookieName = ( usuario );
        Date now = new Date();
        String timestamp = now.toString();
        Cookie cookie = new Cookie (cookieName, timestamp);
        cookie.setDomain ("localhost/databov/nocharpointer");
        cookie.setPath ("/nocharpointer");
        cookie.setMaxAge(7 * 24 * 60 * 60);
        cookie.setVersion ( 0 );
        cookie.setSecure(false);
        cookie.setComment("Cookie de usu�rio");
        response.addCookie (cookie);

        usuario = request.getParameter("user");
        senha = request.getParameter("pass");

        //Fazendo a valida��o
        if( usuario.equals( "" ) || senha.equals( "" ) )
        {
            out.println( "<H3> Por favor preencha corretamente o login e senha</h3>" );
            response.sendRedirect("/erro.jsp");
        }

        try
        {

            query = "SELECT * from cadastro where username = " + usuario + " and senha = " + senha + " ";
            ResultSet results = statement.executeQuery( query );
            statement.close();

            if( results.first() )
            {
                response.sendRedirect("/logado.jsp");

            }
            else
            {
                response.encodeURL("/erro.jsp");

            }

        }
        catch( Exception e )
        {
            System.err.println("Error: Problema ao fechar o banco de dados ");
            e.printStackTrace();


        }

    }

    // Destroys the servlet
    public void destroy()
    {
        try
        {
           connection.close();
        }
        catch( Exception e )
        {
            System.err.println("Erro n�o foi poss�vel fechar o bando");
        }

    }
}

[enterprise-list] NullPointerException

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