PROGRAMMING APPLICATIONS AND FRAMEWORKS

RESTful Web services REST   • Representational State Transfer (REST) is an architectural style for the service of web • The REST is used as a basis for HTTP 1.1 development    • Thus the WWW including servers, proxies, etc... • REST is    • Resource-based   • Focuses on Representations (of data/information/resources)     • Derived using Six Constraints   CONSTRAINTS 1) Client-server 2) Layered System   3) Stateless   4) Cacheable   5) Code-On -Demand (Optional)     6) Uniform Interface   ELEMENTS OF REST STYLE        

Web Service World Wide Web Consortium describes web service as a system of software allowing different machines to interact with each other through network. Web services achieve this task with the help of XML, SOAP, WSDL and UDDI open standards. XML :   The full form of XML is ‘Extensible Markup Language’ which is used to share data on the web and in universal format. SOAP :  Standing for ‘Simple Object Access Protocol’ which is an application communication protocol that sends and receives messages through XML format. It is one of the best ways to communicate between applications over HTTP which is supported by all browsers and servers. WSDL :  Written in XML, WSDL stands for Web Services Description Language and is used to describe web service. WSDL comprises three parts such as Definitions (usually expressed in XML including both data type definitions), Operations and Service bindings. Operations denote actions for the messages supported by a Web service. T

1. Explain the term “distributed systems”, contrasting it from “distributed computing” ? Distributed system : a collection of independent computers that are connected with an interconnection network. Distributed computing : a method of computer processing in which different parts of a computer program are run on two or more computers that are communicating with each other over a network. 2. Compare and contrast the standalone systems with distributed systems, providing examples for advantageous use of both ?  A standalone device is any mechanism or system that can perform its function without the need of another device, computer, or connection. A perfect example of a standalone device is a copy or fax machine, as shown in the picture .   Standalone system  All the components are executed within a single device  Do not need a network Usually one or tightly coupled set of technologies are used to develop (JAVA, .NET) Distributed system The components are

1.Discuss the importance of maintaining the quality of the code, explaining the different aspects of the code quality? code quality is crucial to a company's succes. It goes without saying that the software that we deliver to customers should be of high quality . Our products need to look great and help customers run their business. The fact that they do, is because of the thousands and thousands of lines of code under the hood. •Clarity: Easy to read and oversee for anyone who isn’t the creator of the code. If it’s easy to understand, it’s much easier to maintain and extend the code. Not just computers, but also humans need to understand it. •Maintainable: A high-quality code isn’t overcomplicated. Anyone working with the code has to understand the whole context of the code if they want to make any changes. •Documented: The best thing is when the code is selfexplaining, but it’s always recommended to add comments to the code to explain its role and functions. It ma