NullPointerException Error when calling fillTable()

Question

I can not seem to spot where I get NullPointerException Error when call the method fillTable(). fillTable is called from the button what takes in String from a textField. fillTable is meant to populate a JTable by retrieving Object[][] containing data from a handler class.

private void fillTable(String dataType, String searchBy)
    {
        String[] columnName = {"module name", "Workshop %", "Lecture %", "Tutorial %", "Average %"};
        if(searchBy.startsWith("@"))
        {
            tableModel.setDataVector(pLSHand.gIStudData(dataType, searchBy), columnName);
            table.setModel(tableModel);
        }
        else
        {
            tableModel.setDataVector(pLSHand.gNStudData(dataType, searchBy), columnName);
            table.setModel(tableModel); 
        }
        table.repaint();
    }

Button:

String searchBy = (String)textField.getText();
if(!searchBy.isEmpty())
{
   fillTable("Year",searchBy);
}
else
{

}

Method in the Handler class

public Object[][] gIStudData(String dType, String studID)
    {

        String rQuery = "SELECT * FROM StudAttYear WHERE studentID = '"+ studID +"'";
        data = new Object[1][5];

        if(dType.equalsIgnoreCase("Semester"))
        {
            rQuery = "SELECT * FROM StudAttSem WHERE studentID = '"+ studID +"'";
            data = new Object[2][5];
        }
        else if(dType.equalsIgnoreCase("Year"))
        {
            rQuery = "SELECT * FROM StudAttYear WHERE studentID = '"+ studID +"'";
            data = new Object[1][5];
        }
        else if(dType.equalsIgnoreCase("Week"))
        {
            rQuery = "SELECT * FROM StudAttWeek WHERE studentID = '"+ studID +"' AND number = '"+ weekNo +"'";
            data = new Object[12][5];
        }

        try{
               Class.forName(DRIVER_CLASS);

                connection = DriverManager.getConnection( url,"agile", "adila");
                statement = connection.createStatement();
                results = statement.executeQuery(rQuery);
                int i=0;
                while(results.next())
                {
                     data[i][0] = results.getString("module");
                     data[i][1] = results.getString("workshop%");
                     data[i][2] = results.getString("tutroial%");
                     data[i][3] = results.getString("lecture%");
                     data[i][4] = results.getString("avg%");
                 i++;
                }
           results.close();
           statement.close();
           connection.close();
           } catch (SQLException sqlException) {
           sqlException.printStackTrace();
           System.exit(1);
           }catch(Exception exception) {
           System.err.println("An error happened");
           System.exit(1);
         }
        return data;
    }

Using the same technique in other classes and they seem to work.

The NPE message will tell you which lines are involved with the exception, and you need to start there. If still stuck you should show us which lines those are. — Hovercraft Full Of Eels, Dec 03 '12 at 16:24
@HovercraftFullOfEels eclipse is not showing the line numbers, but I assume its the if statements. — user1873139, Dec 03 '12 at 16:30
@durron597 Sorry, just realised that I haven't declared pLSHand. Thanks for help. — user1873139, Dec 03 '12 at 16:36

score 1 · Accepted Answer · answered Dec 03 '12 at 16:37

1

As stated, pLSHand is not declared elsewhere in your code.

answered Dec 03 '12 at 16:37

durron597

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NullPointerException Error when calling fillTable()

1 Answers1