How to instantiate an object in a JSP page???

I want from a JSP page instantiate an object from a client class, for example, and call its methods; one of these methods return me a RecordSet.
But I don't having success on it. What am I doing wrong??? What would I do??? Have anybody a code sample????
Regards.

Hi,
There's the code that I'm using, they are divided in 3 parts, and I really don't know what is causing this error.
********** CLASS conn ******************
* IT'S THE CLASS THAT DO THE CONNECTION
* AND EXECUTE THE SQL QUERIES
import java.sql.*;
import java.io.*;
public class conn {
public static Connection conn;
public static Statement stmt;
public static void openConn() throws SQLException {
    DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver());
    conn = DriverManager.getConnection("jdbc:oracle:thin:@(DESCRIPTION=(ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.24.8)(PORT = 1521)))(CONNECT_DATA =(SERVICE_NAME = ora_aula)))", "grupo6", "grupo6");
    stmt = conn.createStatement();
public boolean getConectionState() throws SQLException {
    if (conn.isClosed())
      return false;
    else
      return true;
public static void closeConn() throws SQLException {
    stmt.close();
    conn.close();
public static void postSql(String command) throws SQLException {
    stmt.executeQuery(command);
    stmt.executeQuery("COMMIT");
public ResultSet returnSql(String command) throws SQLException {
    return stmt.executeQuery(command);
********** CLASS materia ***************
* IT'S THE CLASS THAT INSTANTIATE THE
* conn CLASS AND PASS TO IT THE SQL
* THAT WILL BE EXECUTED AND RETURN THE
* RECORDSET
import java.sql.*;
public class materia{
   public Integer materia_code;
   public String materia_description;
   private conn myConn = new conn();
   private ResultSet materia_data;
   ResultSet showData(comandosql){
     try {
       myConn.openConn();
       ResultSet data = myConn.retornaSql(sql);
       myConn.closeConn();
       return data;
     catch (SQLException sqlexc) {
       System.out.print(sqlexc);
       return null;
********** jsp PAGE******************
* IT'S THE PAGE THAT INSTANTIATE THE
* materia CLASS AND EXECUTE THE
* STATEMENT, AND WHERE THE ERROR
* IS OCURRING
<%@ page import="java.sql.*" %>
<%@ page import="materia" %>
<HTML>
<TITLE> Products</TITLE>
<%
    out.println("<B> TEST </B>");
    ResultSet rs;
    materia mat = new materia();
   rs = mat.showData("SELECT * FROM PRODUCTS");
// THE ERROR OCURR IN THE STATEMENT ABOVE
// WHAT AM I DOING OF WRONG????
// ... REST OF CODE
%>
</HTML>Thanks for your help.
Regards.
Clayton

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<b><u>1) JAVA file</u></b>
import com.sapportals.htmlb.DropdownListBox;
     import com.sapportals.htmlb.InputField;
     import com.sapportals.htmlb.event.Event;
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     import com.sapportals.portal.prt.component.IPortalComponentContext;
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     * Method          :           getPage()
     * Description      :
     * Input Parameters     :     None
     * Returns          :          Object of Class DynPage
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              private int iFlag=0;
              private int iErrFlag=0;
              /* Variables for storing the information
                      entered by user in each text field */
              private String sFname;
              private String sSname;
              private String sAge;
              private String sExp;
              private String sSkill;
              private String sUnit;
     * Method          :           doInitialization()
     * Description      :
     * Input Parameters     :     None
     * Returns          :          None
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     * Description      :
     * Input Parameters     :     object of Event class
     * Returns          :          None
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                    /*     sets flag to 1 when update button is clicked. */
                    iFlag=1;
     * Method          :           doProcessAfterInput()
     * Description      :
     * Input Parameters     :     None
     * Returns          :          None
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                         InputField ifFirstName = (InputField) getComponentByName("FirstName");
                         InputField ifSecondName = (InputField) getComponentByName("SecondName");
                         InputField ifAge = (InputField) getComponentByName("Age");
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                         InputField ifSkill = (InputField) getComponentByName("Skill");
                         DropdownListBox dlbUnit = (DropdownListBox) getComponentByName("Unit");
                         int iAge,iExp;
                         IPortalComponentRequest request = (IPortalComponentRequest) this.getRequest();
                        IPortalComponentContext myContext = request.getComponentContext();
                         P_SAP_B_CreateUser myNameContainer = (P_SAP_B_CreateUser) myContext.getValue("createUserBean");
                         if(ifFirstName != null)
                              this.sFname = ifFirstName.getValueAsDataType().toString() ;
                         }     // end of if
                         if(ifSecondName!= null)
                              this.sSname = ifSecondName.getValueAsDataType().toString() ;
                         }      // end of if
                         if(ifAge!= null)
                              this.sAge = ifAge.getValueAsDataType().toString() ;
                         }     // end of if
                         if(ifExp!= null)
                              this.sExp = ifExp.getValueAsDataType().toString() ;
                         }     // end of if
                         if(ifSkill != null)
                              this.sSkill = ifSkill.getValueAsDataType().toString() ;
                         }     // end of if
                         if(dlbUnit != null)
                              this.sUnit = dlbUnit.getSelection().toString() ;     ;
                         }      // end of if
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                         /* try block for numeric Exception */
                         try
                             /* checking for any field left blank by the user */
                              if(sFname.equals("") || sSname.equals("") || sAge.equals("")|| sExp.equals("") || sSkill.equals(""))
                                    /* set error flag to 1 in case of any field left blank */
                                    iErrFlag=1;
                              } // end of if
                              else
                                    /* converting Age and Experience fields (String) to integer */
                                     iAge= Integer.parseInt(sAge);
                                     iExp= Integer.parseInt(sExp);
                                   /* setting the boundaries on the value in Age Field */
                                     if(iAge<0)
                                         /* set error flag to 2 in case of age below 0 */
                                         iErrFlag=2;
                                     }// end of if
                                   /* setting the boundaries on the value in Experience field */
                                      else if(iExp<0 ||(iExp/12)>=iAge)
                                          /* set error flag to 3 in case of experience below 0 or exceeding the age in years */
                                          iErrFlag=3;
                                      }// end of else if
                                      /* In case of no error */
                                      else
                                         /* setting the bean variables */
                                         try
                                             Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
                                             Connection con = DriverManager.getConnection("jdbc:odbc:Test");
                                             String query="insert into UserData values(?,?,?,?,?,?)";
                                             PreparedStatement prestat=con.prepareStatement(query);
                                             /* setting the values to be inserted into the user table */
                                             prestat.setString(1,sFname);
                                             prestat.setString(2,sSname);
                                             prestat.setString(3,sAge);
                                             prestat.setString(4,sExp);
                                             prestat.setString(5,sSkill );
                                             prestat.setString(6,sUnit);
                                             prestat.executeUpdate() ;
                                             prestat.close();
                                             con.close();
                                             myNameContainer.setSFname(sFname);
                                             myNameContainer.setSLname(sSname);
                                             myNameContainer.setSAge(sAge);
                                             myNameContainer.setSExp(sExp);
                                            myNameContainer.setSSkill(sSkill);
                                            myNameContainer.setSUnit(sUnit);
                                         } // end of inner try block
                                          catch(Exception sqle)
                                             myNameContainer.setErrMessage("Update failed ! Please try again." );
                                          } // end of catch corresponding to inner try
                                                       } // end of inner else
                                                  } //end of outer else
                               } //end of outer try block
                               catch(Exception e)
                                 /* setting flag to 4 in case of non-numeric age/experience values */
                                 iErrFlag = 4;
                                 /* Displaying error message corresponding to the value of error flag */
                              switch(iErrFlag)
                                /* Empty Field */
                                case 1:myNameContainer.setErrMessage( "Please Fill all the fields");
                                break;
                                /* Invalid Value in the age field */
                                case 2:myNameContainer.setErrMessage( "Enter a valid value in Age field.(Hint : Have you entered Age<0 ?");
                                break;
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                                case 3:myNameContainer.setErrMessage( "Enter a valid value in Experience field.(Hint : Experince should not be negative or greater than your age in months)");
                                break;
                                /* Non-numeric value in the Age/ experience fields */
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                                break;
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     * Method          :           doProcessBeforeOutput()
     * Description      :
     * Input Parameters     :     None
     * Returns          :          None
              public void doProcessBeforeOutput() throws PageException
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                   this.setJspName("P_SAP_B_UserCreationForm.jsp");
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                     if(iErrFlag!=0)
                          setJspName("ErrorPage.jsp");
                     } //end of if
                     /* Displays the user's information as entered in the SQL
                        database after its been uploaded by the user */
                     else if(iFlag==1)
                         setJspName("hello.jsp");
                      } // end of else if
              } // end of doProcessBeforeOutput()
          } // end of P_SAP_B_UserDynPage Class
     } // end of P_SAP_B_User class
* End of File P_SAP_B_User.java
2) Bean
package com.sap.usercreation;
import java.io.Serializable;
public class P_SAP_B_CreateUser implements Serializable
     private String sFname;
     private String sLname;
     private String sUnit;
     private String sSkill;
     private String sExp;
     private String sAge;
     private String errMessage;
     * @return
     public String getSFname() {
          return sFname;
* @return
public String getSLname() {
     return sLname;
* @param i
* @param string
public void setSFname(String string) {
     sFname = string;
* @param string
public void setSLname(String string) {
     sLname = string;
* @return
public String getSUnit() {
     return sUnit;
* @param string
public void setSUnit(String string) {
     sUnit = string;
* @return
public String getSSkill() {
     return sSkill;
public void setSSkill(String string) {
     sSkill = string;
* @return
public String getSAge() {
     return sAge;
* @return
public String getSExp() {
     return sExp;
* @param string
public void setSAge(String string) {
     sAge = string;
* @param string
public void setSExp(String string) {
     sExp = string;
* @return
public String getErrMessage() {
     return errMessage;
* @param string
public void setErrMessage(String string) {
     errMessage = string;
3) The Jsp file i have already posted.
See if you copy this code and paste it wont work as i have not given you full code ,But yes this gives you an overview of how things can be done .
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