Special purpose techniques for data exchange
WebSphere Portal supports special purpose techniques for data exchange.
Cross-portlet linksThis works for IBM and JSR portlets. With the advanced URL generation APIs for portlets, you can have a portlet create a link that points to another portlet, possibly even on a different page, and pass data to that portlet. If at all possible, use the publish/subscribe methods. Use explicit cross-portlet links only where other techniques are not applicable. For example, this can be for communication between IBM and JSR portlets.
For details, refer to the documentation about the portalRenderURL tag and the PortalURLGenerationService. Such links can also be created from a theme JSP that use the portal URL generation tag.
For advanced use cases that require more control over the generated URLs, you can also use the portal state API.
CookiesThe Java Portlet Specification 2.0 adds support for portlets to read and set HTTP cookies. You can share cookies between portlets and other Web applications to track information about the current browser interaction without requiring a server side session and without consuming server resources.
Custom JavaScript data exchangeAs portlets are Web components inside an HTML page, you can use any client side techniques to read, write or exchange data within the markup that portlet provides. This includes sharing data via the page document object model (DOM) or use of client side JavaScript code or libraries.
Parent
Portlet communication
Shared portlet state
Publish/subscribe message based communication
Portlet events based communication
Cooperative portlets
Interoperability between events and cooperative portlets
Event broker
Portlet wires
Public render parameters
Known issues and restrictions with portlet communication
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