GCube Portal Engine

Introduction

To provide the end user with the full functionality of the gCube system, a presentation application, based on the ASL libraries and the featherweight ones, has been implemented.

In gCube the [Liferay portal] is employed as the portlet-hosting platform. Liferay Portal offers a complete platform for building web apps, mobile apps, and web services quickly, using features and frameworks designed for rapid development, good performance, and ease of use. It runs on all major application servers and servlets containers and it is JSR 168 and JSR 286 compliant.

Portlets are using JSR 286 and several other technologies such as Java Server Pages for dynamically generation of HTML/XML documents in response to a client’s request, and the most popular Front-End frameworks such as Angular, React or Vue.

All these technologies are hosted under the Liferay Portal engine.

Main Technologies

JSR 286

JSR (Java Specification Request) 286 establishes a standard API for creating portlets. It constitutes the integration component between applications and portals, and it enables delivery of an application through a portal. Without this standard, each version of an application needed its own portlet API, and each of the various portals required that these portlets should be specifically tailor-made for that portal. Inter-Portlet Communication through events, public render parameters and dynamically generated resources directly through portlets are some of the API's advantages

GWT

Google Web Toolkit (GWT) is an open source Java software development framework that allows web developers to create Ajax applications in Java. It is licensed under the Apache License version 2.0. GWT emphasizes reusable, efficient solutions to recurring Ajax challenges, namely asynchronous remote procedure calls, history management, bookmarking, and cross-browser portability. For all these reasons most portlets use the GWT for a better and more efficient Ajax implementation.

Sencha GXT

Sencha GXT is the fastest, most powerful way to create rich web-based applications using Java.
Sencha GXT uses the Google Web Toolkit (GWT) compiler that allows you to write your applications in Java and compile your code into highly optimized cross-browser HTML5 and JavaScript. Sencha GXT takes GWT to the next level, giving you high-performance widgets, feature-rich templates and layouts, advanced charting, data loaders and stores, and much more.

JSP

Java Server Pages (JSP) is a Java technology that allows developers to dynamically generate HTML, XML or other types of documents in response to a Web client request. The technology allows Java code and certain pre-defined actions to be embedded into static content. The JSP syntax adds additional XML-like tags, called JSP actions, to be used to invoke built-in functionality. Additionally, the technology allows for the creation of JSP tag libraries that act as extensions to the standard HTML or XML tags. Tag libraries provide a platform independent way of extending the capabilities of a Web server. JSPs are compiled into Java Servlets by a JSP compiler. A JSP compiler may generate a servlet in Java code that is then compiled by the Java compiler, or it may generate byte code for the servlet directly. JSPs can also be interpreted on-the-fly reducing the time taken to reload changes.

Other Technologies

GWT-OpenLayers

GWT-OpenLayers is a Java wrapper for the OpenLayers JavaScript API. It allows GWT projects to use the OpenLayers JavaScript API. OpenLayers makes it easy to put a dynamic map in any web page. It can display map tiles and markers loaded from any source. OpenLayers has been developed to further the use of geographic information of all kinds. OpenLayers is completely free, Open Source JavaScript, released under the 2-clause BSD.

jQuery

jQuery is a fast, small, and feature-rich JavaScript library. It makes things like HTML document traversal and manipulation, event handling, animation, and Ajax much simpler with an easy-to-use API that works across a multitude of browsers.