Invalid thread access exception while updating textfield

I'm trying to update a textfield which belongs to another class using a runnable thread, but I'm getting 'invalid thread access' exception.

My code is:

 Thread t2 = new Thread () {

    public void run () {
        System.out.println("t2 thread içindeyim.");
        try {
            String sql =  " RESTORE DATABASE Genius3"+
                          " FROM DISK = '"+collected.getdbpath()+"'"+
                          " WITH MOVE 'GeniusIII_Data' TO 'C:\\SQLDATA\\Genius3.mdf',"+
                          " MOVE 'GeniusIII_Log' TO 'C:\\SQLDATA\\Genius3_1.ldf'";

            Class.forName(driver).newInstance();
            con = DriverManager.getConnection(url);
            stmt = con.prepareStatement(sql);
            rs = stmt.executeQuery();}
            catch (Exception ef) {ef.printStackTrace();}
            finally {

           ekran5.text_1.setText("done");

           }        
    }
};

and the other class which has that textfield in it ;

 public class ekran5 {

public static Label islemlabel;

public static Composite composite_1 ;
public static Label detail;
 public static  Text text_1;
public static void start(){


composite_1 = new Composite(Loader.composite, SWT.BORDER | SWT.EMBEDDED);
composite_1.setBackground(SWTResourceManager.getColor(192,192,192));
composite_1.setBounds(362, 83, 668, 536);

islemlabel = new Label(composite_1, SWT.NONE);
islemlabel.setFont(SWTResourceManager.getFont("Arial CYR", 10, SWT.NORMAL));
islemlabel.setBackground(SWTResourceManager.getColor(SWT.COLOR_GRAY));
islemlabel.setBounds(10, 448, 84, 15);
islemlabel.setText("\u0130\u015Flem Detay\u0131");

text_1 = new Text(composite_1, SWT.BORDER);
text_1.setBounds(10, 469, 628, 37);
}

}

In the finally block, I'm updating the textfield but it gives me an invalid thread access exception because of this.

In SWT only the UI thread is allowed to update widgets try using Display.syncExec to perform all the UI updates. (Alternatively, a UI job can be used.)

Also reading the SWT FAQ would be a wise move, this sounds like a FAQ to me.