Example XML Applications/Languages

Objectives To Review uses of XML To investigate some Language applications of XML XHTML RSS WML Web Services

XML Uses and Languages Uses XML can Separate Data from HTML XML is Used to Exchange Data and Share Data XML and B2B XML Can be Used to Create New Languages XML Applications/Languages XHTML Rich Site Summary - RSS Wireless Markup Language (WML) Web Services (SOAP, REST) EBusiness XML (ebXML)

XML for Data Transfer/Exchange XML can be use to store data (database) Can be used to exchange/share data Need to parse XML document Bit by bit – SAX Create DOM object – DOM Can parse at client or Server SimpleXML uses DOM Demo CDData

XML for RSS Really Simple Syndication Can share headlines and content Can be updated automatically Personalisation of different sites Avoids having to continually check sites News Feeds – See BBC Companies Calendars

RSS Syntax Demo RSSTut.xml Channel : Title, link, description Item : Title, link, description Demo : RSSTut + Stylesheet

RSS Examples Accessing RSS Data –Demo bbcNewsdata and bbsNewsData codebbcNewsdata Using Style sheets fragments - demodemo Demo bbctransrss.php and bbcrssframent.xslt Aggregators Blogger - Yahoo Demowww.yahoo.co.uk

XML for Wireless Markup Language WML for devices that implement WAP Based on internet standards WML is an XML document (validator) This is a sample WML page.

Gateways WML Stored on server – accessed via WAP Gateway Translates into suitable form for mobiles.

WML Decks and Cards WML pages are called DECKS - Demo hello.wml Constructed as a set of CARDS Related to each other with links. Page accessed all the cards in the page are downloaded from the WAP server. Navigation - inside the phone - without any extra access trips to the server Demo ‘hello.wm’ and ‘select.wml’ BBC – WAP Demo

XML for Web Services Designed to support interoperable machine-to-machine interaction over a network Transported using http using REST or SOAP/WSDL Most major sites offer some web services Amazon, ebay, yahoo, payPal

XML Web Services : REST Representational State Transfer Like html forms – GET & POST Response is XML document Simple and popular Demo - Search?appid=YahooDemo&query=Madonna&results=1 Demo – Using Yahoo RestUsing Yahoo Rest

XML Web Services : SOAP Simple Object Access Protocol Requests sent by post – encapsulated in a SOAP envelop Uses WSDL to describe web services Xmethods Amazon -

Advantages of Web Services Interoperability between various software applications running on disparate platforms. Web services use open standards and protocols. By utilizing HTTP, web services can work through many common firewall security measures.HTTPfirewall Allow software and services from different companies and locations to be combined easily to provide an integrated service.