When i'm trying to populate database numbers to jcombobox it shows nullponterexception what is the reason?

Asked Feb 25 '16 at 07:13

Active Feb 25 '16 at 07:22

Viewed 17 times

i'm using simple statement for this and one resultset object also, but When i trying to populate the values to jcombobox it raises nullpointerException even though i checked for !=null also...WHAT is the reason can any one tell me..

 public void myInit()
{
    try
    {
      //register driver
      Class.forName("oracle.jdbc.driver.OracleDriver");
      //establish the connection
      con1 = DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","virat");
      if(con1!=null)
      {
      //create statement 
      st = con1.createStatement();
      }
      if(st!=null)
      {
      //execute login to get values to combobox
      rs1 = st.executeQuery("select empid from employee");
      }
      if(rs1!=null)
      {
      while(rs1.next())
      {
          comboBox.addItem(rs1.getString(1));
      }
      }
    }
    catch(ClassNotFoundException cnf)
    {
        JOptionPane.showMessageDialog(null, cnf);
    }
    catch(SQLException se)
    {
        JOptionPane.showMessageDialog(null, se);            
    }

}

edited Feb 25 '16 at 07:22

asked Feb 25 '16 at 07:13

lohith kumar

Try to post your code? – Abdelhak Feb 25 '16 at 07:17
Based on that out of context code snippet and lack of a stack trace, I would guess that it's the comboBox which is `null` – MadProgrammer Feb 25 '16 at 07:19
It's either the `comboBox` or `getString()` is attempting to return something which has not been initialised. – ifly6 Feb 25 '16 at 07:19
ya i updated code above see – lohith kumar Feb 25 '16 at 07:23
By the way, you know Eclipse can autoformat your code for you, right? `Java > Code Style > Formatter`. – ifly6 Feb 25 '16 at 07:27
Can you attach the stack trace? Maybe rs1.getString(1) returns null – Benefits Feb 25 '16 at 07:40
i don't get ur point can u explain clearly becoz i don't formater much soo please – lohith kumar Feb 25 '16 at 07:43

When i'm trying to populate database numbers to jcombobox it shows nullponterexception what is the reason?

0 Answers0