Re: method always visible by other class

Brandon McCombs <>
Sun, 18 Mar 2007 21:15:43 -0400
Mariano wrote:

Then I have a class called, inside this class there's a
method called GetResultFromPazienti():

The method below is called GetResultFromPazienti2().

package cc;

import java.sql.*;

public class MyDBConn {
    private Connection myConnection;
    private java.sql.Statement stmt;

// ...

the method below is not the same as you specify above.
You never instantiate stmt so maybe that is what is producing the null

public ResultSet getResultFromPazienti2(String query) {
        ResultSet rs=null;
        catch(Exception e){
        return rs;

// ...


After this, I have a class called, from this class I
would call method: getResultFromPazienti2(), class is something like

package cc;
import java.sql.*;

public class Paziente extends javax.swing.JFrame {
        private MyDBConn mdbc;
        private java.sql.Statement stmt;

Is stmt ever used and initialized?
Is mdbc ever initialized? You leave out code that prevents full analysis
so we can't help you.

// ...
// ...

    private void formWindowOpened(java.awt.event.WindowEvent evt)
        ResultSet rs=mdbc.getResultFromPazienti2("select ... from ...
where ...");

        try {
                 // ...
                 // ...
        } catch (SQLException ex) {


At first moment seem that are not problems, infact there's no problem
in compile time, but when I execute project and method
formWindowOpened() is started an "Exception in thread "AWT-
EventQueue-0" java.lang.NullPointerException", where are the
Thank you to all....

The exception should tell you what line the null pointer is on. Does it?

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