How to get the value of the selected item in SelectOneChoice?

First way: set valuePasstrhu attribute to true. By default it will be false so it will return index of the selected item

Second way use the following code:

 public Row getLovRowAtIndex(String lovAttrName, Integer index) {
        Row row = null;
        try {
            DCBindingContainer binding = ADFUtils.getDCBindingContainer();
            JUCtrlListBinding list =
                (JUCtrlListBinding)binding.get(lovAttrName);
            String selectedValue = (String)list.getAttributeValue();
            list.getListIterBinding().setCurrentRowWithKeyValue(selectedValue);
            row = list.getListIterBinding().getRowAtRangeIndex(index);
        } catch (Exception e) {
           System.err.println("Error while getting row from LOV : " + e);
        }
        return row;
    }

Third way: Bind the Value attribute to the binding, when user selects an item then the corresponding value will be stored in to the binding.