Hello Guys
Now, We are removing borders of a portlet in liferay that added using tag as below :

<liferay-portlet:runtime portletName="customSocialNotifications_WAR"  />

You can use below attribute available in same tag as defaultPreferences, which defined below :

Put following code in your portlet JSP page.

<%
StringBundler sb = new StringBundler();
sb.append("<portlet-preferences >");
sb.append("<preference>");
sb.append("<name>");
sb.append("portletSetupShowBorders");
sb.append("</name>");
sb.append("<value>");
sb.append("false");
sb.append("</value>");
sb.append("</preference>");
sb.append("</portlet-preferences>");
%>

<liferay-portlet:runtime portletName="customSocialNotifications_WAR"  defaultPreferences="<%=sb.toString()%>"/>