Getting data from on object!!

Question

Hello!
Well I'm having a problem when I try to get the data from a class i my jsp page.
I have a database conection class and methods to conect to tha database and get the data :
package teste;
public class Data {
    Connection con;
    Detalhes detalhes;
    ArrayList list;
    public Data()throws Exception {       
        try {
            Class.forName("org.gjt.mm.mysql.Driver");
            con = DriverManager.getConnection("jdbc:mysql://127.0.0.1/Loja?user=root&password=131283");            
        } catch (Exception ex) {
            throw new Exception(" Database not found!!" +
                ex.getMessage());
    public void remove() {
        try {
            con.close();
        } catch (SQLException ex) {
            System.out.println(ex.getMessage());
    public Detalhes getDetalhes(int codigo){
        try {
            String selectStatement = "select * from produto where codigo="+codigo;
            PreparedStatement prepStmt = con.prepareStatement(selectStatement);
            ResultSet rs = prepStmt.executeQuery();
            while(rs.next())
                 detalhes = new Detalhes(rs.getString(1), rs.getString(2), rs.getDouble(3), rs.getInt(4));          
        }catch(Exception e){
            return detalhes;
    public ArrayList getList(){
        try {
            String selectStatement = "select * from produto";
            PreparedStatement prepStmt = con.prepareStatement(selectStatement);
            ResultSet rs = prepStmt.executeQuery();
            while(rs.next())
                 detalhes = new Detalhes(rs.getString(1), rs.getString(2), rs.getDouble(3), rs.getInt(4));          
                 list.add(detalhes);
        }catch(Exception e){
            return list;
}    i have too, a context class to put the database conection avalaible:
package teste;
public final class ContextPage implements ServletContextListener {
    private ServletContext context = null;
    Data dados;
    public void contextInitialized(ServletContextEvent event) {
        context = event.getServletContext();
        try {
            dados = new Data();
            context.setAttribute("bookDB", dados);
        } catch (Exception ex) {
            System.out.println("Couldn't create bookstore database bean: " +
                ex.getMessage());
    public void contextDestroyed(ServletContextEvent event) {
        context = event.getServletContext();
        Data dados = (Data) context.getAttribute("bookDB");
        if (dados != null) {
            dados.remove();
        context.removeAttribute("bookDB");              
}I have too a class with methods to store and show the data that i'd got from the conection class:
package teste;
public class Detalhes {
    String titulo, autor;
    Double preco;
    int codigo;
    public Detalhes(String titulo, String autor, Double preco, int codigo) {
        this.titulo = titulo;
        this.autor = autor;
        this.preco = preco;
        this.codigo = codigo;
    public String getTitulo(){
        return titulo;
    public String getAutor(){
        return autor;
    public Double getPreco(){
        return preco;
    public int getCodigo(){
        return codigo;
}and the last class is to intermediate the data flow between Data.class and Detalhes.class.
package teste;
import java.util.ArrayList;
public class GetData {
     Data db;
     int codigo;
     Detalhes detalhes;
     public GetData() {       
    public void setCodigo(int codigo){
        this.codigo = codigo;
    public void setDb(Data db){
        this.db = db;
    public Detalhes getDetalhes()throws Exception{
        detalhes = (Detalhes)db.getDetalhes(codigo);
        return detalhes;
    public ArrayList getList()throws Exception{
        return db.getList();
    public void remove() {
        db.remove();
}and the piece of my page with proble is
<p><b><h1>Resultado:</h1></b></p><br>
<jsp:useBean id="dados" class="teste.GetData" scope="page">
      <jsp:setProperty name="dados" property="db" value="${dados}"/>
</jsp:useBean>    
<jsp:setProperty name="codigo" property="db" value="1"/>So the problem is that when i acess this page i get an error message
could you geve me some advice with some code?
the exception is:
org.apache.jasper.JasperException: Attempt to coerce a value of type "teste.GetData" to type "teste.Data"
     org.apache.jasper.runtime.JspRuntimeLibrary.handleSetPropertyExpression(JspRuntimeLibrary.java:659)
     org.apache.jsp.Resposta_jsp._jspService(Resposta_jsp.java:53)
     org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:105)
     javax.servlet.http.HttpServlet.service(HttpServlet.java:860)
     org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:336)
     org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:301)
     org.apache.jasper.servlet.JspServlet.service(JspServlet.java:251)
     javax.servlet.http.HttpServlet.service(HttpServlet.java:860)
     sun.reflect.GeneratedMethodAccessor67.invoke(Unknown Source)
     sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
     java.lang.reflect.Method.invoke(Method.java:585)
     org.apache.catalina.security.SecurityUtil$1.run(SecurityUtil.java:249)
     java.security.AccessController.doPrivileged(Native Method)
     javax.security.auth.Subject.doAsPrivileged(Subject.java:517)
     org.apache.catalina.security.SecurityUtil.execute(SecurityUtil.java:282)
     org.apache.catalina.security.SecurityUtil.doAsPrivilege(SecurityUtil.java:165)I thank you very much for this help!! All the best!!

Answer 1

Thanks for trying to help me, but I just have done this:
<jsp:useBean id="gDados" class="teste.GetData" scope="page">
      <jsp:setProperty name="gDados" property="db" value="${dados}"/>
</jsp:useBean>    
<jsp:setProperty name="codigo" property="db" value="1"/>
<p><b><h1>${gDados.detalhes.titulo}</h1></b></p><br>and it brings me the excption :
org.apache.jasper.JasperException
     org.apache.jasper.runtime.JspRuntimeLibrary.internalIntrospecthelper(JspRuntimeLibrary.java:365)
     org.apache.jasper.runtime.JspRuntimeLibrary.access$000(JspRuntimeLibrary.java:60)
     org.apache.jasper.runtime.JspRuntimeLibrary$PrivilegedIntrospectHelper.run(JspRuntimeLibrary.java:90)
     java.security.AccessController.doPrivileged(Native Method)
     org.apache.jasper.runtime.JspRuntimeLibrary.introspecthelper(JspRuntimeLibrary.java:306)
     org.apache.jsp.Resposta_jsp._jspService(Resposta_jsp.java:60)
     org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:105)
     javax.servlet.http.HttpServlet.service(HttpServlet.java:860)
     org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:336)
     org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:301)
     org.apache.jasper.servlet.JspServlet.service(JspServlet.java:251)
     javax.servlet.http.HttpServlet.service(HttpServlet.java:860)
     sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
     sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
     sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
     java.lang.reflect.Method.invoke(Method.java:585)
     org.apache.catalina.security.SecurityUtil$1.run(SecurityUtil.java:249)
     java.security.AccessController.doPrivileged(Native Method)
     javax.security.auth.Subject.doAsPrivileged(Subject.java:517)
     org.apache.catalina.security.SecurityUtil.execute(SecurityUtil.java:282)
     org.apache.catalina.security.SecurityUtil.doAsPrivilege(SecurityUtil.java:165)have youany other suggestion?Thanks!!