A short presentation on Java based portal platforms having little comparative views on Oracle WebCenter and Liferay.

1. Portal Platforms
There are many reliable Java portal platforms, some renowned platforms
are available as Open Source as well as proprietary. Some Open Source
projects dedicated to providing robust, full-featured, commercial-quality,
and freely available Portal are:

2. Jetspeed
Jetspeed-2 is an Open Portal Platform and Enterprise Information
Portal, written entirely in open source under the Apache license in
Java and XML and based on open standards. All access to the portal
is managed through a robust portal security policy. Within a
Jetspeed portal, individual portlets can be aggregated to create a
page. Each portlet is an independent application with Jetspeed
acting as the central hub making information from multiple sources
available in an easy to use manner.
The latest version of Jetspeed, Version 2.2.1, most significantly
introduces the Jetui client-side customization engine. Version 2.2.0
was our first release conformant to the Java Portlet 2.0 Standard.
All releases prior, such as the 2.1.x releases, are conformant to the
first Java Portlet Specification, the Java Portlet 1.0 Standard.

3. Pluto
Pluto is the Reference Implementation of the Java Portlet
Specification. The current version of this Portlet specification is JSR 168
1.0 Portlets are designed to run in the context of a portal. They are
written to the Portlet API. Pluto implements the contract, the Portlet
API, between portlets and portals. Pluto is a portlet container.

4. JBoss Portal
JBoss Portal provides an open source platform for hosting and serving
a portal's Web interface, publishing and managing its content, and
customizing its experience. While most packaged Portal frameworks
help enterprises launch Portals more quickly, only JBoss Portal delivers
the benefits of a zero-cost open source license combined with a
flexible and scalable underlying platform.

5. Liferay
Liferay is a portal designed to deploy portlets that adhere to the
Portlet API (JSR 168). Many useful portlets are bundled with the portal
(Mail, Document Library, Calendar, Message Boards, etc).
Liferay has been declared "Best Open Source Portal" by InfoWorld in
2007

6. eXo Platform
The eXo platform is a powerful Open Source - JSR 168 compliant –
enterprise portal built from several modules. It's based on Java Server
Faces, Pico Container, JbossMX and AspectJ.

7. Propreitary Portal Platform
Oracle WebCenter Portal is a web platform for creating intranets,
extranets, composite applications, and self-service portals. It provides
users a more secure and efficient means to consume information and
interact with applications, processes, and users.
It is built on top of the JSF-based Oracle Application Development
Framework
There are three main products that make up the WebCenter portfolio
and they can be purchased together as a suite or individually:
• Oracle WebCenter Content (includes WebCenter Imaging)
• Oracle WebCenter Sites
• Oracle WebCenter Portal

8. Comparison of Oracle Webcenter and
Liferay
Advantages of Oracle Portal:
• Oracle offers a full-stack suite for development (including JSF and
Portlets): Oracle Application Development Framework (ADF)
• Oracle JDeveloper offers good support for ADF.
• Everything from one product line increases efficiency (database,
application server, ESB, IDE, Portal, …) – at least in theory

9. Comparison of Oracle Webcenter and
Liferay
Disadvantages of Oracle Portal:
• High initial costs
• Complex, heavyweight product (compared to Liferay Portal)
• Proprietary
• Communication between Portlets is not implemented using the
standard JSR-286, but a custom proprietary solution
• The entire platform feels unfinished. There are many bugs or
features altogether missing from components. The other major
concern is that this product is built on ADF.

10. Comparison of Oracle Webcenter and
Liferay
Advantages of Liferay Portal:
• Open source
• Drastically lower initial costs
• Lightweight product (1-Click-Install, etc.)
• Can run on almost every popular Java server. Compatible with
platforms which are running the Java Runtime Environment and an
application server
• Liferay Portal Enterprise comes with many useful portlets, and in
fact Liferay portal has maximum utility portlets as compared to
other open source Portal Frameworks, which are JSR 168 compliant
and can be used in any Portal Framework with little changes.

11. Comparison of Oracle Webcenter and
Liferay
Disadvantages of Liferay Portal:
• Not everything is from one product line (this cannot be considered
as disadvantage always)
• Portlets are still Portlets. Although Liferay is lightweight, realizing
Portlets still problematic as it does with a proprietary product
References:
https://dzone.com/articles/pros-and-cons-%E2%80%93-when-use
https://www.g2crowd.com/compare/liferay-liferay-digital-experience-
platform-vs-oracle-webcenter-content