Returns the bullet of the line at the given index.
@param index the index of the line
@return the line bullet
@exception SWTException <ul>
<li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
<li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
</ul>
@exception IllegalArgumentException <ul>
<li>ERROR_INVALID_ARGUMENT when the index is invalid</li>
</ul>
Returns the bullet of the line at the given index.
@param index the index of the line
@return the line bullet
@exception SWTException <ul> <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> </ul> @exception IllegalArgumentException <ul> <li>ERROR_INVALID_ARGUMENT when the index is invalid</li> </ul>
@since 3.2