Design and Implementation of Online Bookstore System Based on Java

随着科技的迅猛发展，互联网成为人们日常生活中的重要工具，人们的生活越来越离不开网络。在网络的热潮下，电子商务也高速发展，给人们的生活和消费观念带来了极大的变化，网络购物成为人们生活中不可或缺的一部分。与其他商品相比，图书信息易于判断和选择，适合于网上交易，再者网上交易价格比实体店价格低，这些都让图书成为炙手可热的网上交易商品类型。所以，设计一个实用的网上书城系统具有现实的经济价值。 本文根据用户使用习惯及购物需求，基于Java技术，设计并实现了网上书城系统，主要研究内容如下： 1、本文基于Java技术和MySQL数据库设计并实现了一个网上书城系统，主要分成前台和后台这两部分，前台部分的主要...With the rapid development of technology, Internet becomes an important tool in our daily life. The rapid development of e-commerce, changing people's lives and consumer attitudes, online shopping has become an indispensable part of people's lives. Compared with other commodities, book information is easy to judge. Moreover, online transaction price is cheaper than the store price. Because of thes...学位：工程硕士院系专业：软件学院_工程硕士(软件工程)学号：X201323226

Applets vs JavaScript

Client-side scripting languages are used to design the interactive web pages used by consumers to view web applications. With the tremendous growth in technology, numerous client-side scripting languages are being introduced into daily life. However, applets were the first technology introduced to create dynamic web pages and were the popular programming for over a decade. Later, JavaScript was introduced for the same purpose and is the most popular scripting language used by the developers today. Both the applets and JavaScript have their advantages and disadvantages. The usage of these two technologies is dependent on the performance and other general requirements of the web application that is being developed. Hence, this paper compares JavaScript and applets concerning network, memory, performance, and security to help developers find the most efficient use between these two technologies based on the requirement of the application. This paper will also discuss other features that need to be considered while developing the application

Performance measurements of Web services

Web services are rapidly evolving application-integration technologies that allow applications in heterogeneous environments to communicate with each other. In this thesis we perform a measurements-based study of an e-commerce application that uses web services to execute business operations. We use the TPC-W specification to generate a session-based workload. The component level response times and the hardware resource usage on the different machines are measured. The component level response times are extracted from the application server logs. From the results it is seen that as the workload increases the response times of the web services components increase. From the hardware resource usage it is clear that web service components require more processing time due to the processing of XML data required in each web service call. The method used in this thesis allows us to study the impact that different components can have on the overall performance of an application

Effect of gap lenghts of sphere-sphere electrodes on air breakdown level under lightning impulse

Impinging jets are a best method of achieving particularly high heat transfer coefficient and are therefore employed in many engineering applications. In this study we seek to understand the mechanism of the distributed heat on the curve surface with the goal of identifying preferred methods to predicting jet performance. The goals that have been achieved in the numerical results displayed are determine the influence of impingement jet characteristics on thermal and flow field on a curve surface, determine the variation of Nusselt numbers (NuD) along the curve surface in order to understand the heat transfer characteristics and study the effect of position (in the center, in the mid and in the end) and angle (α=90°, 60° and 30°) of jet impingement on curve surface, different Reynolds numbers (ReD) in range of (5000, 6000, 7000, 8000 and 9000). The program, which was extracted results it is (GAMBIT 2.4.6) and (FLUENT 6.3), simulation is (2-D) in submerged jet flow and the continuity, momentum and energy equations were solved by means of a finite volume method (FVM). This study covers the effect of different Reynolds numbers (ReD) on average Nusselt numbers (Nuavg) and local Nusselt numbers (NuD). From the result, the average Nusselt numbers (Nuavg) increased with the increase of Reynolds numbers (ReD) for all cases, in comparison between different positions (center, mid and end), of nozzle on curve surface at angle (α=90°) the maximum value of average Nusselt numbers (Nuavg=388.3) is found when the nozzle locate in the end followed by the mid position and smallest value of average Nusselt numbers (Nuavg=182.25) in the center of curve surface. In case of slant angle (α=60º) the maximum value of average Nusselt numbers (Nuavg=387.47) is found when the nozzle locate in the end followed by the mid position and smallest value of average Nusselt numbers (Nuavg=308.3) in the center of curve surface

The Online Bookstore

Nowadays, the network plays an import role in people’s life. In the process of the improvement of the people’s living standard, people’s demands of the life’s quality and efficiency is more higher, the traditional bookstore’s inconvenience gradually emerge, and the online bookstore has gradually be used in public. The online bookstore is a revolution of book industry. The traditional bookstores’ operation time, address and space is limited, so the types of books and books to find received a degree of restriction. But the online bookstore broke the management mode of traditional bookstore, as long as you have a computer, you can buy the book anywhere, saving time and effort, shortening the time of book selection link effectively. The online bookstore system based on the principle of provides convenience and service to people

Bridging test and model-driven approaches in web engineering

In the last years there has been a growing interest in agile methods and their integration into the so called "unified" approaches. In the field of Web Engineering, agile approaches such as test-driven development are appealing because of the very nature of Web applications, while model-driven approaches provide a less error-prone code derivation; however the integration of both approaches is not easy. In this paper, we present a method-independent approach to combine the agile, iterative and incremental style of test-driven development with the more formal, transformation-based model-driven Web engineering approaches. We focus not only in the development process but also in the evolution of the application, and show how tests can be transformed together with model refactoring. As a proof of concept we show an illustrative example using WebRatio, the WebML design tool.Publicado en Lecture Notes in Computer Science book series (LNCS, vol. 5648).Laboratorio de Investigación y Formación en Informática Avanzad

Towards a UML profile for modeling WAP applications

UML (Unified Modeling Language) is one of the most used languages to specify and document informatics applications. However, UML is a generalpurpose language, so it often lacks of elements to model and represent concrete concepts of specifics domains. As a solution, OMG (Object Management Group) has created the profiles, a mechanism to extend the syntax and semantics of UML to express more specific concepts of certain application domains. In this work we present a UML profile for modeling WAP (Wireless Applications Protocol) applications. The main goal of the proposed profile is to extend UML to provide specifics elements (labeled classes, stereotypes, tagged values and constraints) that allow software developers to modelWAP applications. The expressiveness of the UML diagrams allows modeling important stages of the process of common applications; nevertheless, the modeling process of WAP applications is still a too specific domain that can be hardly dealt with in its entirety without extending the language. In the process exists navigational, design and construction issues that cannot be modeled using the traditional elements of UML. However, by using the specific elements created by the proposed profile, these issues can be completely solved, and even a greater expressiveness can be obtained.Facultad de Informátic

Web page performance analysis

Computer systems play an increasingly crucial and ubiquitous role in human endeavour by carrying out or facilitating tasks and providing information and services. How much work these systems can accomplish, within a certain amount of time, using a certain amount of resources, characterises the systems’ performance, which is a major concern when the systems are planned, designed, implemented, deployed, and evolve. As one of the most popular computer systems, the Web is inevitably scrutinised in terms of performance analysis that deals with its speed, capacity, resource utilisation, and availability. Performance analyses for the Web are normally done from the perspective of the Web servers and the underlying network (the Internet). This research, on the other hand, approaches Web performance analysis from the perspective of Web pages. The performance metric of interest here is response time. Response time is studied as an attribute of Web pages, instead of being considered purely a result of network and server conditions. A framework that consists of measurement, modelling, and monitoring (3Ms) of Web pages that revolves around response time is adopted to support the performance analysis activity. The measurement module enables Web page response time to be measured and is used to support the modelling module, which in turn provides references for the monitoring module. The monitoring module estimates response time. The three modules are used in the software development lifecycle to ensure that developed Web pages deliver at worst satisfactory response time (within a maximum acceptable time), or preferably much better response time, thereby maximising the efficiency of the pages. The framework proposes a systematic way to understand response time as it is related to specific characteristics of Web pages and explains how individual Web page response time can be examined and improved