The Google Web Toolkit(GWT) offers a large set of widgets that look familiar to known Google applications. However, the panels in Google applications like GMail™ and Google Calendar™ have rounded corners. The RoundedPanel widget adds rounded corners that look identical to the rounded corners as in GMail™. With one line of code and one css line a standard GWT panel or other widget will have the rounded corners.
GWT RoundedPanel widget

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