can't put anything to hashtable

[beebob]

Hi all,

I have just changed my JDK, from 1.5.0 to 1.6.0, and also change my Netbeans, from NB 4.0 to NB 5.5. I've got a problem with my code, which I wrote on NB 4.0 + JDK 1.5.0.. I fail to put anything into my hashtable when I try the code on NB 5.5 + JDK 1.6.0. Here is the code:

 
    public Hashtable getIDUser (HttpServletRequest request, HttpServletResponse response, String sqlWhere, String namaUser) 
    throws SQLException, IOException  {
        ServletOutputStream out = response.getOutputStream();
 
        String sqlGetUserID = "SELECT ID, Nama, Password FROM " + strTblUser + " ";
        if (sqlWhere == null) {
            sqlGetUserID = sqlGetUserID;
        } else {
            sqlGetUserID = sqlGetUserID + sqlWhere;
        }
 
        // check 1
        out.println("sqlGetUserID : " + sqlGetUserID + "<br>");
 
        int a = 1;
        try {
            Class.forName ("sun.jdbc.odbc.JdbcOdbcDriver");
            Connection con1 = DriverManager.getConnection(DBurl, "", "");
            Statement stmt1 = con1.createStatement();
            ResultSet rs1 = stmt1.executeQuery(sqlGetUserID);
 
            // check 2
            ResultSetMetaData rsmd = rs1.getMetaData();
            int colCount = rsmd.getColumnCount();
            out.println("colCount: " + colCount + "<br>");
 
            Hashtable HTArea = new Hashtable();
 
            while (rs1.next()) {
                HTArea.put(new Integer(a), rs1.getString(0));
                a = a + 1;
            }
 
            // check 3
            int isiHT;
            isiHT = HTArea.size();
            out.println("isiHT: " + isiHT + "<br>");
 
            rs1.close();
            stmt1.close();
            con1.close();
            return HTArea;
    }
    catch (SQLException se) {
            /** just catch */
    }
        catch (java.lang.Exception ex) {
            /** just catch */
    }
        return new Hashtable();
    }    
 
 

If you look at my code, you will see that I have put some lines to check the code. I have no problem with Check 1 and Check 2, but when I see Check 3, I know something was happen. There is nothing in my Hashtable. Did I do something wrong when I try to put ResultSet into my hashtable? Can someone help me? Thank you.


Regards,
Novan Ananda

[r035198x]

Hi all,

I have just changed my JDK, from 1.5.0 to 1.6.0, and also change my Netbeans, from NB 4.0 to NB 5.5. I've got a problem with my code, which I wrote on NB 4.0 + JDK 1.5.0.. I fail to put anything into my hashtable when I try the code on NB 5.5 + JDK 1.6.0. Here is the code:

 
    public Hashtable getIDUser (HttpServletRequest request, HttpServletResponse response, String sqlWhere, String namaUser) 
    throws SQLException, IOException  {
        ServletOutputStream out = response.getOutputStream();
 
        String sqlGetUserID = "SELECT ID, Nama, Password FROM " + strTblUser + " ";
        if (sqlWhere == null) {
            sqlGetUserID = sqlGetUserID;
        } else {
            sqlGetUserID = sqlGetUserID + sqlWhere;
        }
 
        // check 1
        out.println("sqlGetUserID : " + sqlGetUserID + "<br>");
 
        int a = 1;
        try {
            Class.forName ("sun.jdbc.odbc.JdbcOdbcDriver");
            Connection con1 = DriverManager.getConnection(DBurl, "", "");
            Statement stmt1 = con1.createStatement();
            ResultSet rs1 = stmt1.executeQuery(sqlGetUserID);
 
            // check 2
            ResultSetMetaData rsmd = rs1.getMetaData();
            int colCount = rsmd.getColumnCount();
            out.println("colCount: " + colCount + "<br>");
 
            Hashtable HTArea = new Hashtable();
 
            while (rs1.next()) {
                HTArea.put(new Integer(a), rs1.getString(0));
                a = a + 1;
            }
 
            // check 3
            int isiHT;
            isiHT = HTArea.size();
            out.println("isiHT: " + isiHT + "<br>");
 
            rs1.close();
            stmt1.close();
            con1.close();
            return HTArea;
    }
    catch (SQLException se) {
            /** just catch */
    }
        catch (java.lang.Exception ex) {
            /** just catch */
    }
        return new Hashtable();
    }    
 
 

If you look at my code, you will see that I have put some lines to check the code. I have no problem with Check 1 and Check 2, but when I see Check 3, I know something was happen. There is nothing in my Hashtable. Did I do something wrong when I try to put ResultSet into my hashtable? Can someone help me? Thank you.


Regards,
Novan Ananda

You are returning a new (empty) hashtable at the end of your method. You should return the hashtable that you were adding stuff to.

[JosAH]

            Hashtable HTArea = new Hashtable();
 
            while (rs1.next()) {
                HTArea.put(new Integer(a), rs1.getString(0));
                a = a + 1;
            }
 

This throws an exception because column indexes start at one, not zero. At the
end (after the catch) you return an empty hash set.

kind regards,

Jos

[BigDaddyLH]

catch (SQLException se) {
            /** just catch */
}
catch (java.lang.Exception ex) {
            /** just catch */
}

Maybe it's my inner Buddhist, but I'm always looking for examples where a person's behaviour is also his immediate punishment ;-)

[JosAH]

catch (SQLException se) {
            /** just catch */
}
catch (java.lang.Exception ex) {
            /** just catch */
}

Maybe it's my inner Buddhist, but I'm always looking for examples where a person's behaviour is also his immediate punishment ;-)

Even atheists only muffle exceptions away for a very good reason and even then:
they document them.

kind regards,

Jos ;-)