Client side aggregation in WebSphere portal8.0

                                                          The following client-side programming model guidelines apply only to themes that support Client-Side Aggregation (CSA), primarily the Page Builder theme. The Portal 8.0 theme and the Portal 7.0.0.2 theme do not support CSA. 

Client side APIs available for portlets :- 
General prerequisites for using the client-side APIs are as follows:

• A CSA theme is active for the given page where the portlet is deployed.
• The render type iWidget has been activated. To do this, use the XML configuration interface or modify the metadata.properties in WebDAV, or select Client Side Aggregation - Rendering in the Page Properties portlet.

Explicitly disabling portlets for client-side mode As the portal cannot automatically detect the instances where portlets use APIs that are not compliant with client-side mode, you can use the portlet preferencecom.ibm.portal.preventRenderType to disable client-side rendering for standard portlets if you set one of the values to iwidget. You can set this preference on all customization levels. In the portlet.xml you declare this setting as follows:  <?xml version="1.0" encoding="UTF-8"?> <portlet-app [...]> <portlet> [...] <portlet-name>NonClientSidePortlet</portlet-name> <portlet-class>my.server.side.Portlet</portlet-class> [...] <portlet-preferences> <preference> <name>com.ibm.portal.preventRenderType</name> <value>iwidget</value> [...] <read-only>true</read-only> </preference> </portlet-preferences> </portlet> [...] </portlet-app>