Total Pageviews

Saturday, May 30, 2015

Liferay: IPC via Server Side Events

IPC (Inter Portlet Communication) in Liferay can be implemented in different ways and  I've already written an article on Public render parameter mechanism. In this article, we'll see Event based IPC. As Public Render Parameters, this concept was also introduced in JSR 286.

As per IPC using Events, portlet can publish/send and process/receive the event. This mechanism works flawlessly with inter and intra WARs.

1. Event deceleration in Event Publisher Portlet's portlet.xml
Full portlet.xml will look like as follows:

2. Event definition in Event Receiver Portlet's portlet.xml
Full portlet.xml will look like as follows:
3. Event Publishing Portlet's Controller Class

Invoking Publish Event method

4. Event Processing Portlet's Controller Class and fethching parameter's value
Note: 'QName' is a nothing but a qualified name of the parameter. Usage of QName minimizes chances of having two identical events.

Liferay: IPC using Public Render Parameters

IPC (Inter Portlet Communication) in Liferay can be implemented in different ways and  we'll see one among the possibilities, i.e. Public Render Parameter. This concept was introduced in JSR 286.

The central idea of this concept is to share a normal parameter across all deployed portlets despite of the fact that they lie in same WAR or in different.

1. In portlet.xml in the end of </portlet> tag we have to define the name of parameter

2. In portlet.xml in the end of <portlet-app> tag we have to define the identifier with the name of parameter

Full portlet.xml file will look like as follows:

Setting Parameter:

Reading Parameter:

Note: If render parameters need to be shared among two different WARs, and you have to set parameter in portlet 1 and read in portlet 2, For achieving this, we have to add definition of render parameter in the portlet.xml file of both the WARs.