How to set docklayoutpanel borderwidth in gwt

Heres my code snippet, 开发者_开发百科whats wrong?

mydocklayoutpanle.getElement().getStyle().setProperty("borderWidth", "4");

All i need is to show the borders. Any suggestion would help.

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Try dockPanel.getElement().getStyle().setProperty("border","black solid 4px");