Assessment of portlet quality: Collecting real experience

Owing to the current complexity of portals, vendors of portal frameworks are striving to bring component-based development to the Web: ‘portlets’. Portal users find the portal screen split into a number of sections, each containing separate ‘portlets’, that run or link to the application elements to which the particular user has the appropriate access rights. Taking into account that the success of a portal depends on customers using it and then returning to it, its quality must be assured. If the quality of a portal is to be guaranteed, the first step is to ensure that the portal is built with portlets which have a “good” quality level. Bearing all this in mind, this paper has set as its objective the development of a portlet quality model which includes different measures and which is able to determine the quality level of a specific portlet. In addition, the model has been applied to a concrete portlet: as a result, the quality level for the different characteristics that make up the portlet quality model has been assessed.     

基于Jetspeed2.0的Portlet二次开发

门户为内部和外部用户访问Web站点的信息和应用提供了一个单一的访问入口,一个Portlet是门户中提供特殊服务或信息的窗口.介绍了基于公开源代码的企业信息门户软件Jetspeed,分析了最新版的Jetspeed 2.0的各个组成部分,并通过一个例子详细介绍了在Jetspeed2.0的基础上进行Porrlet二次开发的过程.基于Jetspeed2.0很容易对Porrlet进行二次开发,编写一些自己的Portlet,通过对这些Portlet的个性化设置,实现整个门户网站的个性化.     

From page-centric to portlet-centric Web development: Easing the transition using MDD

Portlet syndication is the next wave following the successful use of content syndication in current portals. Portlets can be regarded as Web components, and the portal as the component container where portlets are aggregated to provide higher-order applications. This perspective requires a departure from how current Web portals are envisaged. The portal is no longer perceived as a set of pages but as an integrated set of Web components that are now delivered through the portal. From this perspective, the portal page now acts as a mere conduit for portlets. Page and page navigation dilute in favor of portlet and portlet orchestration. However, the mapping from portlet orchestration (design time) to page navigation (implementation time) is too tedious and error prone. For instance, the fact that the same portlet can be placed in distinct pages produces code clones that are repeated along the pages that contain this portlet. This redundancy substantiates in the first place the effort to move to model-driven development. This work uses the eXo platform as the target PSM, and the PIM is based on Hypermedia Model Based on Statecharts. The paper shows how this approach accounts for portal validation/verification to be conducted earlier at the PIM level, and streamlines both design and implementation of eXo portals. A running example is used throughout the paper.     

Improving a portlet usability model

Second-generation portals are far from being monolithic pieces of software. Their complexity calls for a component-based approach where portlets are the technical enabler. That being the case nowadays portals tend to be constructed by means of portlets, i.e. a multi-step, user-facing application to be delivered through a Web application. The proposal for and ample support given to the WSRP (Web Services for Remote Portlets) portlet standard predict an emerging portlet market. A main requirement for the blossoming of this market is the existence of portlet quality models that assist portal developers to select the appropriate portlet. This paper focuses on usability. The aim, therefore, is to develop a usability model for portlets. The paper presents such a model and its realisation for a sample case.

一种基于MVC模式的Portlet开发框架的设计与实现

为了解决Portlet应用提供商、门户提供商之间互不协调的问题,JCP组织发布了Portlet规范来提供不同门户和Portlet之间的互操作性。JSR规范中定义的繁杂的编程接口和Portlet运行时上下文给Portlet开发带来了特殊性和复杂性。引入一种基于MVC思想的Portlet开发框架OPDS,其提供了简洁的编程接口和配置方式,利用此框架进行开发将大大简化开发的复杂性,同时可加强Portlet应用中业务逻辑资源的复用性。     

一种面向Web服务的门户组件机制的设计与实现

通过门户组件(Portlet)来访问以Web服务形式提供的软件服务并展现其结果是通过门户(Portal)访问Web服务的一个核心问题。文中提出一种面向Web服务展现的Portlet(以下简称WSPortlet)机制来解决上述问题,通过遵循业界主流的Portlet规范,使用XSLT来对XML文档进行转换等途径保证了WSPortlet的规范性、有效性和灵活性,并且自主研发实现了WSPortlet系统(以下简称WSPS)。     

Web应用开发平台的元建模研究

传统的Web应用开发方法面临系统复杂度增加、需求不断变更等挑战，导致开发效率低下，系统难重用。本文基于MDA方法学，采用标准建模语言UML和元建模语言MOF，定义了针对Web应用的面向对象建模语言UML-EBP。通过分析UML-EBP元模型结构、语义以及相关模型实例的表述，表明UML-EBP元模型可以很好地应用于Web应用系统开发过程，从而快捷简便地实现Web应用系统开发，并使得系统容易扩展、复用。     

远程门户组件的Web服务的研究与实现*

Web服务解决了异构环境中的互操作问题,但是并没有提供信息展示和用户交互的方法。采用远程门户组件的Web Service（WSRP）技术,提出了WSRP平台的概念模型,分析了远程门户组件的映射原理,研究了远程门户组件的对象池及管理算法,设计实现了一个远程门户组件的Web服务的运行平台,解决了Web 服务的展现问题,同时解决了Internert上的门户组件共享问题。     

Multi-device application middleware: leveraging the ubiquity of the Web with webinos

The broad range of connected devices has turned the Internet into a ubiquitous concept. In addition to desktop and laptop PCs, the Internet currently connects mobile devices, home entertainment systems, and even in-car units. From this ubiquitous evolution towards sensor-rich devices, the opportunity arises for various new types of innovative software application. However, alongside rises the issue of managing the increasing diversity of device characteristics and capabilities. As device fragmentation grows, application developers are facing the need to cover a wider variety of target devices and usage scenarios. In result, maintaining a viable balance between development costs and market coverage has turned out to be an important challenge when developing applications for a ubiquitous ecosystem. In this article, we present the webinos platform, a distributed Web runtime platform that leverages the Web for supporting self-adaptive cross-device applications. In order to enable the development of such immersive ubiquitous applications, we introduce and evaluate the concept of a context-aware federated overlay architecture.     

HTML5-based system for interoperable 3D digital home applications

Digital home application market shifts just about every month. This means risk for developers struggling to adapt their applications to several platforms and marketplaces while changing how people experience and use their TVs, smartphones and tablets. New ubiquitous and context-aware experiences through interactive 3D applications on these devices engage users to interact with virtual applications with complex 3D scenes. Interactive 3D applications are boosted by emerging standards such as HTML5 and WebGL removing limitations, and transforming the Web into a real application framework to tackle interoperability over the heterogeneous digital home platforms. Developers can apply their knowledge of web-based solutions to design digital home applications, removing learning curve barriers related to platform-specific APIs. However, constraints to render complex 3D environments are still present especially in home media devices. This paper provides a state-of-the-art survey of current capabilities and limitations of the digital home devices and describes a latency-driven system design based on hybrid remote and local rendering architecture, enhancing the interactive experience of 3D graphics on these thin devices. It supports interactive navigation of high complexity 3D scenes while provides an interoperable solution that can be deployed over the wide digital home device landscape.     

基于 Portlet 的高性能计算应用集成组件

高性能计算 Web 应用社区经常需要封装不同类型的应用,封装过程需开发或调整源代码。因此,社区管理员不能快速满足应用封装需求,特别是作业参数相对复杂的应用。通过分析不同作业管理系统的作业提交和管理命令、不同学科领域的高性能计算应用程序的使用方式、通用作业描述语言的结构和语义,本文提出了一种基于 portlet 的高性能计算应用集成组件,设计和实现了应用需求描述模板、作业提交页面动态渲染引擎、作业参数存储和填充方法,从而提供了基于 WEB 页面的应用封装、动态生成作业提交 Web页面和作业描述并提交作业的功能,并且支持以历史作业的输入数据填充作业提交页面的功能。分析及实例表明,该组件能够有效提高应用封装的响应速度,用户能够方便的提交作业和重用复杂的作业参数,具有良好的可移植性和扩展性。     

Analyzing Architectural Evolution Issues of Multimedia Frameworks

The growing complexity in the development of Web-based services in general, and multimedia services in particular, makes necessary the application of sound development methods. New multimedia devices, coding algorithms, network protocols, etc., are continually appearing but, unfortunately, current solutions for developing multimedia applications do not accurately support architectural evolution issues for already deployed applications. Thus, the latest Software Engineering technologies should be applied to the development of open, reusable, and high-quality multimedia and Web-based software. In this paper, we apply component and framework technologies, two of the current trends in Software Engineering, to the development of multimedia services over the Web, presenting and comparing widespread solutions in use today.     

Standards for second-generation portals

By integrating applications and resources, portals let users access information in a simple, straightforward manner. Currently, most portals let users create one or more personal pages composed of portlets - interactive Web mini-applications. Until recently, no standards for portlets existed, and thus consuming remote portlets in a generic way or deploying portlets in one portal server that were developed in a different one has been impossible. Two standards released in Fall 2003 - the Web Services for Remote Portlets (WSRP) and the Java portlet specification - address these problems. This articles outlines these standards and presents a typical architecture for a standards-based portal.     

Management of a parameter sweep for scientific applications on cluster environments

The GEOsciences Network (GEON, www.geongrid.org ) is a large‐scale collaborative cyberinfrastructure project involving information technology and geoscience researchers from multiple institutions. The GEON infrastructure provides portal, middleware, and data resources to facilitate scientific discovery for domain scientists using applications, tools, and services. It consists of both a service‐oriented Web/Grid framework and application toolkits, using the Web service and portlet programming model to represent applications. Based on those grid environments, we have developed the SYNSEIS (SYNthetic SEISmogram) tool within the GEON infrastructure to support personalized experiments in seismology. In this paper, we present an overview of SYNSEIS from a user point of view, and demonstrate how one can use a simple management scheme to perform a parameter sweep and distribute the work in computational resources, using a scientific application that was not specifically designed to perform parameter sweeps. The performance advantages to be gained by using this scheme with scientific codes for dealing with a large number of jobs on computational grids are very substantial. In particular, we identify the earthquake simulations in the SYNSEIS tool as an example application that can benefit from running jobs on computational resources and subsequently promote the sharing of computational resources among partner sites involved in the GEON project. Finally, we also discuss the parallel scaling behavior of our primary earthquake simulation application. Copyright © 2010 John Wiley & Sons, Ltd.     

MobiTran:一种面向智能手机的PC版Web应用转化技术

随着移动互联网的快速发展,人们可以通过包括智能手机和平板电脑在内的移动计算设备来访问和使用Web应用。然而,目前已有的Web应用大多是针对PC设计的,因此通过移动计算设备直接访问时,可能出现信息显示不全、界面布局混乱、用户体验变差、需要耗费较多流量等问题。重新开发符合移动设备特性的Web应用是一种最直接的解决方案,但是开发成本和代价较大,并且同时维护PC版和移动版两个不同的应用版本也会带来更高的成本。提出一种面向开发者的Web应用移动版本半自动转化技术并实现了支持工具MobiTran:首先,对PC版本Web应用的界面进行自动转化,使之适应移动设备的屏幕尺寸;然后,通过支持开发者手工对界面的样式和布局进行修改,定制拆分子页面以控制数据流量,同时加入适应移动设备操控特点的元素;最终,生成一个供移动设备访问的移动版本Web应用。对主流网站的测试结果表明:MobiTran可以将原网页自动地转化为适合移动设备宽度的新网页,转化后的网页清晰无溢出并可以较大限度地维持新页面与原页面风格一致;在自动转化过程中,可以较少地丢失页面信息并较大限度地保证原页面的功能;转化后的新页面相比原页面消耗数据流量较小。     

页面流模型驱动的Web应用框架研究

随着业务需求的日渐庞大,构筑大规模web应用系统变得愈加复杂。各种Web应用框架的出现,为应用开发人员提供了相当多的便利。然而目前大多数的Web应用框架仅为Web应用定义了一个层次清晰、分工明确的编程模型,实现这个模型仍然需要手工编写大量代码,而且基于XML的页面流配置文件往往冗长而难以维护。针对这些问题,论文提出了一种页面流模型驱动的Web应用开发框架,它以页面流模型的设计为核心,根据需求分析定制应用的整体业务流程,并给出了支持该框架的Web应用开发工具PFlowWeb。最后介绍一个由PFlowWeb开发的基于Web的文件共享交换系统的应用案例。实践表明,运用该平台可以有效提高大中型Web应用系统的开发效率,增强系统的健壮性和可扩展性。     

Mobile Web services: a new agent-based framework

Mobile devices and server applications often run on different platforms, which can make integration problematic. Web services might offer a solution, but they typically include XML protocols that are too "heavy" for mobile devices. In this article, we describe agent-based mobile services framework. It uses wireless portal networks and eliminates XML processing on mobile clients. It also offers dynamic service selection and rapid application development and deployment for Web service providers.     

网络化数据采集系统的研究和设计

针对底层设备的日益复杂性以及网络技术在设备层的深入应用,基于OPC标准和Web Services技术,研究并设计了一个标准的网络化数据采集系统。首先提出了系统架构,并对服务器端和客户端的开发作进一步展开,最后给出了实例应用。这是一种新型的数据采集方法,为复杂设备的协同服务以及企业信息的垂直集成提供了技术支撑。     

Applying model-driven engineering to the development of Rich Internet Applications for Business Intelligence

Business Intelligence (BI) applications have been gradually ported to the Web in search of a global platform for the consumption and publication of data and services. On the Internet, apart from techniques for data/knowledge management, BI Web applications need interfaces with a high level of interoperability (similar to the traditional desktop interfaces) for the visualisation of data/knowledge. In some cases, this has been provided by Rich Internet Applications (RIA). The development of these BI RIAs is a process traditionally performed manually and, given the complexity of the final application, it is a process which might be prone to errors. The application of model-driven engineering techniques can reduce the cost of development and maintenance (in terms of time and resources) of these applications, as they demonstrated by other types of Web applications. In the light of these issues, the paper introduces the S^m4RIA-B methodology, i.e., a model-driven methodology for the development of RIA as BI Web applications. In order to overcome the limitations of RIA regarding knowledge management from the Web, this paper also presents a new RIA platform for BI, called RI@BI, which extends the functionalities of traditional RIAs by means of Semantic Web technologies and B2B techniques. Finally, we evaluate the whole approach on a case study—the development of a social network site for an enterprise project manager.