Second: Detailed service-oriented service architecture
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Microsoft and Sun reach a reconciliation, and the joints create SOA.
SUN President and COO Jonathan Schwartz said in a recent company meeting, "Collaboration with .NET means only to meet the needs of users. For example, we are trying to achieve interoperability between Visual Studio and Java Studio Creator, We are also working hard to implement a unified architectural thinking when using these two technical systems to develop SOA applications. "
Microsoft is busy preparing indigo. It will be an important part of the next generation of Windows operating system Longhorn.
BEA Systems, Oracle. At the same time, some small vendors, such as Infravio and Cape Clear, are also working on the establishment of their own SOA. ?
IBM has announced in Toronto, which will be in Austin, Beijing, Delhi and Hasler New SOA Design Center.
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What is SOA?
??? SOA why there is such a big charm, what can I bring us, why it has brought such a big shock for IT, and I also brought new hope for IT.
??? SOA is a service-oriented architecture, soa, it is important to note that SOA is not a specific implementation technology, it is an abstract concept and guideline, we can use any of today's maturity Technologies implementation, accurate SOA is a component model. Simple point, a large application in a conventional manner consists of different functional modules, and in SOA, these functional modules are replaced by the concept of functional services, and these so-called modules are defined by the service a good interface and contract. The definition of these interfaces is carried out in a neutral manner, which is independent of the hardware platform, operating system, network architecture, and programming language that implements these services. Because of this, all kinds of services in a large system, even other applications provided by different software vendors can interact in a unified and universal way.
??? Say that this will involve another concept "loose coupling", in software engineering, everyone has learned about the impact on system development in software development. The lower the coupling, the more flexible system development, and it is easier to maintain. The service-oriented architecture is a "loosely coupled" system architecture that refers to the functionality of the application service in the code.
Services differ from previously developed components or class functions, we have implemented only functional components implemented by class or function, etc., which are called in a part in the system, and will be closely related to other related parts after compiling Become a whole, while being passively exists, and can only work to compile in it. The service is to engage some of the functions of the software, making it independently, and in logical relationships and running applications become a hierarchy, because of independent operation, it accepts requests from all authorized objects, making services You can provide the same functions for multiple applications, greatly increase the degree of software reuse, reduce development and maintenance costs. In addition, the inter-service inter-interface interface uses the definition of neutrality, so the system is flexible and easy to change, and the trial is used to apply miniaturized distributed deployments in the future, and on the other hand, the internal structure and implementation of each service consisting of the entire application. When changing, the application will not be affected and implicated, and continue to run.
What can SOA do?
??? SOA stems from the needs of the company's flexible business extension, but also from software developers' pursuit of software multiplexing technology. Maybe SOA will vibrate a large number of traditional developers or developers who provide solutions to companies, because it will become a revolutionary change in software, and the company's application developers will be an idea or the sublimation of thought . The technology of technology is directly brought about the overall change of the solution, and the solution for service framework is adapted to express rapid changes in the business. ??? Below I will give an example to explain this change, assume a multinational car group with 300 branches, and there are many manufacturing plants and sales companies, and there is a large number of suppliers and distributions. Business. They implement them to pass various order data, suppliers and manufacturers to change their supplies and production according to the market, and different branches have different business systems, and the data of these systems will summarize the headquarters, then this is created Will be a highly counted and very complex software process. Once the business system that needs to be adapted, the business system of certain branches will no longer be so simple, it will be from bottom to affect the entire software process, which will be used by the cost and investment. Unacceptable. By using the WSDL interface flexibility in operation, each company can maintain their existing systems, but only match the WSDL interface and develop new service-level agreements, so they do not have to fully refactor their software systems. Doing so, whether it is the change in the business system within the branch, or the supplier has no system changes, and the interface has remained the stability of the entire business system through these interfaces.
On the other hand, in the sales and warehouse in ERP, as an example, when we rose these two modules to the level of the application service, we will bring new enlightenment to our business application development. The warehouse is reflected on the user UI on the one hand, and on the other hand based on some intermediate definition such as WSDL, we can easily define some service-level business interfaces, and these interfaces are relatively stable, regardless of the internal treatment of the library system. How much change, while the sales system can easily get its business regulations and data, and this interaction is cross-platform, cross-language, cross-hardware, cross-regional, meaning, how much is the number of deployment of sales systems, The language developed, and its developers, we do not need to force the requirements, the previous sales module can increase the service-level interface through this method, and have guaranteed good interactions and loose coupling of other systems. In this way, the fast extension will be implemented, especially for the development of large projects, and service-oriented enough frames will show this advantage.
??? Thought changes come from the power of demand, but the changes in thought can let us find new opportunities. The new achievements of the SOA model give us an unreasonable enterprise solution to let users have a new experience in the information system, so that developers and developers have new development experiences and knowledge accumulation, and make the market Smell kenssen people find new markets, we can write components that need to deal with certain aspect information, we can write each trial service, such as computing services, audio processing services, these services we can on the Internet or The LAN is released in a fee or free of charge, and the user can call this feature in the application you developed by the user. In this way, we greatly saved resources and bind scattered computing resources in a new way. These are no longer myths, in a lot of mature technologies, we can easily achieve this.
What technology can achieve SOA?
Since SOA is just a so-called component model, we must use some existing technologies to implement it, like DOCM, CORBA, WebService, we can use these technologies to implement SOA, before WebSercie, due to various technologies On the description of the service, there is no big breakthrough on the cross-platform, open, easy to use, so SOA is tightly used in some powerful manufacturers and some large projects, while the appearance of WebService makes SOA propose Everything is achieved, and the concept of SOA, XML, WebService overnight, spread throughout the world, and has arrived in a wide range of applications. So here I have to make WebSerice as one of the important contents. What is WebService?
Since the reason for Web Service naming may cause misunderstandings of many developers and developers, it is considered that the web service is based on the web browsing service provided by HTTP or straightforward considered B / S application. In fact, this view is completely wrong, completely in understanding a new thing in the direction, Web Service and HTTP web services are completely different, and it is not the so-called B / S application.
??? Web service is known from the literal Web service (not a web server), the concept of service has been mentioned earlier, Web Service is a technology that uses HTTP request to provide component object services for other applications, we can He is thinking as a remote object call technology, a technology that is more open than DCOM / CORBA, more easy to implement remote object service.
??? Web service and application uses an XML-based protocol to communicate with remote calls. All interface information on the web service, including the service structure through another descriptive language, this descriptive language is also defined by XML, we call it WSDL (Web Services Web Services Definition) LANGUAGE). Through WSDL we can describe interface information in a generic format, in the application portion, can be restored in a common way and call the interface.
??? We can use any of the languages or tools to package some of the application services for other access. Through this cost-effective way we can easily implement functional multiplexing, distributed computing, including the SOA in which the article is being elaborated.
??? At present, all popular mainstream development tools can be easily created or called Web Service, such as Delphi 6-7, various Java tools, VB, VS.NET, CB, etc. We can also convert COM automatically to Web Service to Web Service, these good supports, have created a good foundation for the popularity of Web Service, and the emergence of Web Service has also eliminated this platform, tool, language. Taoist ditch, developers can choose to develop applications that they are familiar with, do not need to waste a lot of time to learn unfamiliar language or tools for a consumption.
SOA and web service?
??? Using the XML Web Service's support to implement the service-oriented architecture is a re-match. Whether an XML-based WSDL or SOAP is independent of any language and platform. SOAP itself is not absolutely needed, but it is a common message delivery system, and the WSDL description can be parsed and used for any language. Therefore, you can use almost any programming language and a platform that supports WSDL to implement member services in SOA.
