i tried as you said but no luck yet.
i have clicked on the cell with the comboBox and now i am trying to select a value from the combo but it is always throwing an Exception Widget not found of Type ComboBOx.
Is there anything i am missing in here..
I found the Solution i need to use Ccombo in place of Combo
CCombo combo = bot.widget(widgetOfType(CCombo.class));
SWTBotCCombo combobox = new SWTBotCCombo(combo, null);
combobox.setSelection(Value); // set the text