public ScalarDataModel() 
{
        this(null);
}

Construct a new ScalarDataModel with no specified wrapped data.

 public ScalarDataModel(E scalar) 
{
        super();
        setWrappedData(scalar);
}

Construct a new ScalarDataModel wrapping the specified scalar object.

Parameters:

scalar - Scalar to be wrapped (if any)

 public int getRowCount() 
{
        if (scalar == null) {
	    return (-1);
        }
        return (1);
}

If there is wrappedData available, return 1. If no wrappedData is available, return -1.

 public E getRowData() 
{
        if (scalar == null) {
	    return (null);
        } else if (!isRowAvailable()) {
            throw new NoRowAvailableException();
        } else {
            //noinspection unchecked
            return (scalar);
        }
}

If wrapped data is available, return the wrapped data instance. Otherwise, return null.

 public int getRowIndex() 
{
        return (index);
}

 public Object getWrappedData() 
{
        return (this.scalar);
}

 public boolean isRowAvailable() 
{
        if (scalar == null) {
	    return (false);
        } else if (index == 0) {
            return (true);
        } else {
            return (false);
        }
}

Return true if there is wrappedData available, and the current value of rowIndex is zero. Otherwise, return false.

 public  void setRowIndex(int rowIndex) 
{
        if (rowIndex <  -1) {
            throw new IllegalArgumentException();
        }
        int old = index;
        index = rowIndex;
	if (scalar == null) {
	    return;
	}
	DataModelListener [] listeners = getDataModelListeners();
        if ((old != index) && (listeners != null)) {
            Object rowData = null;
            if (isRowAvailable()) {
                rowData = getRowData();
            }
            DataModelEvent event =
                new DataModelEvent(this, index, rowData);
            int n = listeners.length;
            for (int i = 0; i <  n; i++) {
		if (null != listeners[i]) {
		    listeners[i].rowSelected(event);
		}
            }
        }
}

 public  void setWrappedData(Object data) 
{
        if (data == null) {
            scalar = null;
            setRowIndex(-1);
        } else {
            scalar = (E) data;
            index = -1;
            setRowIndex(0);
        }
}