Java Web Services CSCI 4300

1
Java Web Services CSCI 4300

• Diagrams from the Sun Java Web Services Tutorial,
• http//java.sun.com/webservices/docs/1.6/tutorial/
  doc/

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What are Web Services?

• Business-to-Business (B2B) communication
• Packaged in XML SOAP messages

3
Example Travel Agent
4
Service-Oriented Architecture (SOA)

• Needs
• Mechanism for discovering services (registry)
• Language for specifying service contract (Web
  service semantic)

5
Simple Object Access Protocol (SOAP)

• Envelope top-level element, represents entire
  message
• Header optional info to guide delivery and
  processing by multiple actors, e.g. shipping,
  logging, accounting
• Body contains request / response info
• Fault carries error messages

• lt?xml version"1.0"?
• ltsoapEnvelope xmlnssoap"gt
• ltsoapHeadergt
• ... ...
• lt/soapHeadergt
• ltsoapBodygt
• ... ...
• ltsoapFaultgt
• ... ...
• lt/soapFaultgt
• lt/soapBodygt
• lt/soapEnvelopegt

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Interfacing SOAP with Proprietary business process
7
Example SOAP over AJAX

• Using a WS package to handle SOAP encoding

8
XHttpRequest lifecycle
9
Java XML Binding (JAXB)

• Marshalling collecting data into XML
• Binding generating Java classes to represent XML

10
How Binding Works
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Old-school remote Java RMI
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Remote Java using Web Services Model (JAX-RPC)
13
Another View of JAX-RPC

• This shows the JAX-RPC runtime and HTTP/SOAP
  transport
• In this case client and server are both Java

14
Yet Another View

• Showing the role of WSDL to coordinate client and
  server
• In his case the client is not necessarily in Java!

15
Java XML Registry (JAXR)

• Java API overlaid on native registry systems
• A registry allows location of objects

16
WSDL (Fujitsu version)
17
WSDL (Sun version)
18
UDDI Architecture
19
Acknowledgements

• Webservices strategy http//www.webservices-strat
  egy.com/
• SOAP/proprietary interface http//www.ebizq.net
• SOAP over AJAX diagrams http//www.ibm.com/develo
  perworks/webservices/library/ws-wsajax/
• Web services architecture http//www.w3.org/2003/
  Talks/0317-ws-intro/
• Fujitsu WDSL diagram xml.fujitsu.com
• RPC diagrams http//www.onjava.com/pub/a/onjava/2
  002/04/24/jax-rpc.html
• Figure 1 http//dev2dev.bea.com/lpt/a/345
• JAX-J2EE www.vsj.co.uk