Zugl.: Paderborn, Fachhochsch. der Wirtschaft, Diplomarbeit

Stuttgart, Univ., Fachstudie, 2005.

Stuttgart, Univ., Diplomarb., 2005.

Stuttgart, Univ., Diplomarb., 2005.

Σκοπός της εργασίας αυτής ήταν η θεωρητική ανάλυση των web services και η υλοποίηση ενός ηλεκτρονικού καταστήματος. Για να γίνει κατορθωτή η υλοποίησή του χρησιμοποιήθηκε ένα σύστημα διαχείρισης περιεχομένου, το Joomla. Το Joomla είναι ένα βραβευμένο σύστημα διαχείρισης περιεχομένου το οποίο μας δίνει τη δυνατότητα να οικοδομήσουμε ιστοσελίδες και ισχυρές online εφαρμογές .Είναι γραμμένο σε php, αποθηκεύει δεδομένα MySQL και περιλαμβάνει χαρακτηριστικά όπως η προσωρινή αποθήκευση σελίδας , RSS feeds, printable εκδόσεις των σελίδων, αναβοσβήνει ειδήσεις, blogs, δημοσκοπήσεις και έρευνα. Με τη βοήθειά του δημιουργήσαμε ένα ηλεκτρονικό κατάστημα και συγκεκριμένα ένα ηλεκτρονικό βιβλιοπωλείο που περιέχει δυο κατηγορίες βιβλίων. Με κλικάρισμα σε κάθε βιβλίο προβάλλονται οι λεπτομέρειες του προιόντος και δίνεται η δυνατότητα αγοράς του. / -

Made available in DSpace on 2014-06-12T15:59:16Z (GMT). No. of bitstreams: 2 arquivo4984_1.pdf: 2006892 bytes, checksum: 224264401a8274ab07b0eb4b22c3ec68 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2006 / A tecnologia Web Services está se tornando a mais importante solução para prover a comunicação entre aplicações heterogêneas, contribuindo enormemente para o avanço na área de desenvolvimento de sistemas distribuídos. Uma conseqüência dessa popularidade é a existência de mais de setenta Web Services toolkits disponíveis para uma variedade de plataformas e linguagens de programação. Além disso, várias aplicações em áreas como, por exemplo, e-commerce, computação científica, saúde e finanças estão sendo expostas como Web Services. Dessa forma, o fato de estar sendo adotada por muitas empresas como a infra-estrutura para desenvolver seus sistemas, aumenta a demanda pela sua eficiência, uma vez que desempenho é um importante parâmetro da qualidade do serviço. O problema é que o desempenho de Web Services é uma questão em aberto, uma vez que sua eficiência foi sacrificada para prover simplicidade, interoperabilidade e flexibilidade. Dessa forma, os desenvolvedores deveriam avaliar as condições de desempenho das aplicações Web Services, pois sua ineficiência pode limitar sua aplicabilidade em algumas situações.O principal objetivo dessa dissertação é viabilizar a avaliação de desempenho de Web Services toolkits, propondo diretrizes que foram desenvolvidas baseando-se nos gargalos de desempenho de Web Services. A partir dessas diretrizes, foi elaborado um processo que tem como objetivo uniformizar a avaliação de desempenho de toolkits e facilitar a escolha do toolkit ideal para desenvolver uma aplicação. Também será apresentado o utilitário JWSPerf (Java Web Service Performance) que, juntamente com outras ferramentas, automatiza algumas tarefas desse processo, reduzindo o tempo e os custos necessários para sua execução

Master of Science / Department of Computer Science / Daniel Andresen / Web services have become quintessential in web application development. RESTful web services are one way of providing interoperability between computer systems on the internet. REST-compliant web services allow requesting systems to access and manipulate textual representations of web resources using a uniform and predefined set of stateless operations. These services, which are online APIs, can be accessed from various applications and the results can be used to offer specific functionality to users. This project consists of an Android app, a Server application and a Client application. The Server application exposes a REST API (Web Services developed using REpresentational State Transfer (REST) protocol) using, which the consuming client applications can make use of various functionalities as services across the network. The Android app would be installed in the smart phone present in each vehicle of the fleet, this app would send live location data to the database using the REST API. The manager uses the client application to track the vehicles in real time, the manager can also choose to track a particular vehicle. The API could also be used to integrate the services with other systems. This project serves to a wide variety of users, from small local businesses owning tens or hundreds of vehicle to parents who would like to track the location of their children in real time. This project aims to help the managers/owners better control and track the vehicles. Also, the exposed API could be used by other developers to customize or extend this application. This project is easy to install, use and hence friendly for users with even minimal computer skills.

Este trabalho de mestrado apresenta a modelagem, a prototipação e os resultados do desenvolvimento de um middleware para composição dinâmica de Web Services denominado DWSC-M (Dynamic Web service Composition Middleware). O objetivo principal desse middleware é permitir que serviços sejam compostos dinamicamente considerando aspectos de qualidade de serviço na escolha dos serviços que fazem parte de um fluxo de composição. Para complementar o funcionamento do middleware DWSC-M foram propostos dois algoritmos para seleção de Web Services: o primeiro utiliza seleção aleatória e o segundo utiliza distância Euclidiana para seleção de serviços e considera, para tal finalidade, os parâmetros de QoS enviados pela requisição do cliente do serviço / This work presents the modeling, the prototype and the results of the developing of a middleware for dynamic composition of Web Services named DWSC-M (Dynamic Web Service Composition Middleware). The main focus of this middleware is to allow services being dynamically composed, considering aspects of quality of service in the choice of services that are part of the composite flow. Complementing the operation of the DWSC-M middleware two algorithms were proposed for Web Services selection : the first one uses Random selection and the second one uses Euclidean Distance for the selection of services and considers for this purpose the QoS parameters sent by the client service request

Geographic information is critical to GIS applications located remotely for executing business operations. GIS applications need to interoperate to be able to share information for analysis and decision making process. Heterogeneity and complexity of information models and structures limit the data flow and application interoperation. Advancements in Internet technologies provided new opportunities for delivering spatial information to remote users. However, spatial data delivered is in proprietary structures, limiting the utility to GIS applications. To enable information flow between GIS applications a portable data modeling approach is necessary. However, geographic information is inherently complex to model. A comprehensive and standardized vocabulary to model characteristics of geographic entities is required. Furthermore applications with the need to share information should have an agreement on information structure and content exchanged. This research presents GML representation to provide interoperable spatial data services. The objective is achieved by providing an open framework to model, encode and delivery geographic information. The results of this research show that it is possible to develop interoperable spatial data services through service oriented architecture.

Web services transactions have some unique characteristics. A Web transaction may be composed of a number of individual Web services, executed across multiple loosely coupled autonomous systems. Each Web service may be executed on an independent system belonging to an independent provider. There raises the question whether Web transactions can and should be maintained as a single business unit in a similar way to how transactions are maintained in classical database systems. In classical database systems, the transaction management protocol and mechanism are constrained by the primary properties of atomicity, consistency, isolation and durability (ACID). These ACID properties are the cornerstone of maintaining data integrity in transaction management. However, ACID properties were meant for centralised systems and are better suited for short transactions. Unlike short transactions, Web services transactions may be long-running; they can take hours or even days depending on the application. Composing certain actions from loosely coupled distributed business processes across multiple distributed applications is one of the essentials of Web services transactions. The classic ACID model, which is tightly coupled, is therefore seen as too rigid to support all the requirements of the new Web transactions model. The research proposes a system that increases throughput while maintaining the consistency and correctness required by the particular applications that are using the model; the system is known as AuTrA (Adaptable user-defined Transaction relaxed Approach). AuTrA allows relaxation of each ACID property. The model is adaptable to meet different situations with different characteristics. For instance, in some cases it will be appropriate to relax atomicity, whereas in others it may be appropriate to relax isolation and atomicity while maintaining consistency. The research explores how transaction support for Web services can be customised to suit the needs of varying applications and result in improved service. The AuTrA prototype has been implemented. The experimental results show that the AuTrA application is able to support the basic features of Web services transaction management, allowing users to specify their correctness requirements, and it can increase throughput of transactions in models in a flexible and reliable manner. Additional facilities allow users to specify application-specific, non-ACID criteria that can increase throughput. Safeguards have also been implemented to prevent execution of inappropriate user specifications, such as relaxation of properties that may damage data integrity. AuTrA can be used as a tool by software developers who need to compose applications from independent Web services and who wish to build applications which result in improved performance while maintaining application-required consistency.