Android------Web service overview

What is a Web Service?

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Web Services is an application component
Web Services uses open protocols for communication
Web Services are independent (self-contained) and can be self-described
Web Services can use UDDI to discover
Web Services can be used by other applications
XML is the foundation of Web Services
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Web Service is a software system that supports the interoperability of different machines between networks, a self-contained, self-describing, and modular application
It can be described, published, and invoked in a network, and can be seen as a network-based, distributed, modular component.

Web Services enables your application to become a Web application.
Web Services Publishing, finding, and using the Web

WEB Services is built on the basis of common protocols, such as HTTP, SOAP, UDDI, WSDL, and so on.
These protocols have no inclination in the choice of operating system, programming language and object model, so they have strong vitality.

Usually what we call WebService is a remote server that exposes some kind of service, or understands that it exposes a feature to the outside.
or method, and we can programmatically invoke the service to get the information we need without having to think about what language the method is written in and how it is implemented.

Elements of the WEB services platform:
SOAP (Simple Object Access Protocol)
UDDI (general description, Discovery, and integration)
WSDL (Web Services Description Language)

What is SOAP?
(Simple Object access Protocol)
The basic Web Services platform is XML + HTTP.

SOAP refers to the Simple Object Access Protocol
SOAP is a communication protocol
SOAP is used for communication between applications
SOAP is a format for sending messages
SOAP is designed to communicate over the Internet
SOAP independent of Platform
SOAP independent of language
SOAP based XML
SOAP is simple and extensible
SOAP allows you to bypass the firewall
SOAP will evolve as a standard.

Soap is a lightweight, simple, XML-based protocol that is designed to be used in a distributed environment to exchange formatting and curing information in a simple protocol
SOAP allows one application to send an XML message to another application, and a SOAP message is a single message that is routed from the SOAP sender to the SOAP recipient
Any application can act as the sender and receiver of the message.
Soap only defines the message structure and protocol for message processing, independent of the underlying transport protocol.
SOAP relies on XML documents to build, and a message is a specific XML document.

What is WSDL?
WSDL (Web service Description Language) Web Service Description Language
WSDL is an XML-based language that describes Web services and how to access Web services.

WSDL refers to the Network Service Description Language
WSDL is written using XML
WSDL is an XML document
WSDL is used to describe network services
WSDL can also be used to locate network services
WSDL is not a standard

is an XML language used to describe a Web service, which describes the functions, interfaces, parameters, return values, etc. of a Web service and facilitates user binding and invoking services.

What is UDDI?
UDDI (Universal Description, Description and integration) Unified description, Discovery, and consolidation protocols
UDDI is a directory service through which enterprises can register and search for WEB services.

UDDI refers to generic descriptions, discoveries, and integrations (Universal Description, Discovery, and integration).
UDDI is a directory for storing information about Web services.
UDDI is a directory of network Service interfaces described by WSDL.
UDDI is routed through SOAP.
UDDI is built into the Microsoft. NET platform.

Two features of UDDI:
Web-based
Distributed

By using a Uddi,webservice provider, you can register a Web Service to allow other enterprises to invoke the enterprise registration
Web Service. The Web service provider uses the UDDI Registry's web interface to add information from the Web serviced that he provides to UDDI
Registration Center. The Web service can be discovered and invoked

Users of the Web service also find and discover the services they need through the UDDI registry. When a Web service consumer
Once you have found the service you need, you can bind yourself to the specified Web service provider, and then call the other's service based on the WSDL document that the webservice corresponds to.

Reference:

http://blog.csdn.net/lyq8479/article/details/6420398

Http://www.w3school.com.cn/webservices/ws_platform.asp

Android------Web service overview