J2EE and .NET are the two representative camps of the middleware application server, let us take a look at their true face.
J2EE
J2EE's full name is Java2enterpriseEdition, which is a leader of Sun Company, and various manufacturers develop and have been widely recognized industrial standards. Many large applications such as IBM, BEA, Oracle, etc. in the industry are actively involved in the development and implementation of J2EE standards. Therefore, J2EE is open from the beginning of the open line. Many manufacturers submit programs and formulate specifications, which make J2EE easy to absorb these manufacturers over the years of experience in applying development, system design and integration. Of course, these manufacturers have a forecast of market demand and new technological development, as well as their own unique perspectives, will continue to be reflected in J2EE norms. With such a soil, J2EE products can fully meet the current changing and increasingly complex commercial applications, and will soon become a new system and integration of enterprises to build new systems and integration, extending existing systems. Therefore, the huge business opportunities and profits have made all vendors to improve J2EE more efforts, resulting in J2EE powerful vitality.
J2EE Application Server is in an intermediate layer, a front-end client layer, and has a corporate information system layer behind:
Client layer
The client layer is in the inside of the firewall of the company, which can be a browser running on the client layer, Java-based program, Swing, COM; or other web-type programming environment, access to protocols such as HTTP, HTTPS, IIOP Resources within the backend application server. It is worth mentioning that applet, it is a small client program that requires a browser JVM (Java virtual machine) to perform, we can implement a part of the business logic to be implemented with Applet. As a client application, it provides a more friendly graphical interface that can directly call EJB (EnterpriseJavabean in the business logic layer, of course, can also open an HTTP join with the Web layer's servlet for communication.
2. Application Service Layer
In general, this layer contains representative logic and business logic that supports client requests. Indicates that the logic layer is implemented by the JSP and Servlets displayed by the display dynamic HTML / WML page. Their main role is to accept and verify the data input by the user, transmit the data to the back-end business logic layer, and return the result of the business logic layer to the client layer. The business logic layer is used to meet the needs of financial applications such as finance, telecommunications, retail, and is implemented by EJB (EnterpriseJavabean). EJB relies on EJB Container to achieve transaction, life cycle, status management, resource pool and security. J2EE has three EJBs:
Session bean, indicating the interaction of the client program and the J2EE server. When the client program is executed, the session bean and related data will be deleted.
Entity beans, represents records in the database. When the client program is aborted or the server is shut down, the data of the entity bean is still saved in the database, and does not disappear
Message-Driven BEAN is an EJB triggered by message, which will monitor the message. Once the news arrives, it will do the corresponding operation.
3. Enterprise Information System Layer
Enterprise Information System (EIS) layer is a combination of existing applications, such as packaging applications, proprietary systems, etc. It can include Enterprise Resource Planning (ERP), large host transaction (CICS, IMS), database system, customer relationship management (CRM), data warehouse, financial, OA, and other legacy information systems. For such applications, it has become a big event in the enterprise. The application service layer is through JDBC, JCA these J2EE standards and JCAADAPTER for different applications to access the enterprise information system. J2EE1.3 specification has been issued by Java Connector Adapter, which has made a unified specification for access to Package applications such as ERP, CRM, and some system software such as MQSeries, Email services. For future, J2EE will work hard in WebServices and JCA. Provide a standard approach to implement WebServices in Java through standard WebServices models. In terms of Web Services, the functionality of security Web Services is provided using Oasis's SAML standard. Add asynchronous message mode in JCA to increase the connection method of the background system. Of course, other aspects such as JSP and EJB will continue to be improved. JSP will support standard Tag Library in the browser side, improve the model - view - control architecture to achieve the level of ASP.NET. On EJB, support for asynchronous messages and Web Services will be the direction. With the establishment of Liberty Alliance, J2EE will also find solutions (similar to Microsoft Passport service). For multimedia support and java swings are in the formulation.
On the one hand, the impact of new technologies is huge; on the other hand, new technologies have driven business model, and companies continue to move its traditional business to the Internet.
Java / J2EE
Java is a language that is born makes the program everywhere. Now you don't have to worry about what hardware and operating system. Large to IBM mainframe mainframe, small to hand-held mobile phones can run Java's program, which means that the Java app you wrote can flow everywhere. The programs that have been spent to spend a lot of human and labor have no longer exist. But Java is just a programming language, which is unable to provide many of the functions required for enterprise applications. Under the leadership of Sun, now has J2EE (Java 2 Enterprise Edition), which is standard for enterprise applications. Enterprises can use it to prepare an enterprise-class application, which provides information for enterprise applications. Transaction integrity, reliable messaging, etc. Since the 2,000 years of BC, more and more companies build their key applications on the web application server that supports J2EE standards. Some of the mainstream J2EE application servers can support the stability, availability, security, performance, scalability, and more required for enterprise applications.
Xml
XML is a structured data expression. There is a respective data expression between various systems, such as relational databases, file servers, and user-defined data expressions, which must be understood when applying this information data, and explains them in the program Once the data structure changes, the application has also changed, which is shackled on the development of business applications, and it is difficult to integrate between different systems. With the birth and development of XML, inter-system, cross-industrial applications are very simple, this structured data expression makes the application no need to understand the specific data physical location, data structure add and delete the application. The impact is very small. Each industry has gradually established a data dictionary of the industry, which promotes the general use of XML. XML allows data to flow. Webserve
Some people say that WebServices will truly implement the compute network, some people say that WebServices will change the current IT competition, and Sun's CEOSCOTT MCNEAAaly said that Web Services will be a top peak in Sun's business development, Bill Gates think it is Microsoft .NET core. In fact, Web Services is more extensive in it is a leap forward of distributed computing models, which truly solves distributed computing problems, which is also scientists working hard. Using huge, ubiquitous Internet computing power to achieve extensive calculations and enterprise services. One fact has established, only ASCII technical standards have been supported by ASCII technical standards since IT, and is applied to almost all-in-laws, and now Web Services is very likely to become such standards again. Really becoming bridges connected between companies and businesses, making companies can extend their business services to the world, promoted to the Internet, and truly becoming a link in the business value chain of dynamic development. For future business models, business services, provide technical implementation methods for cross-enterprise, cross-industry, and cross-regional services.
Today's reduced enterprise operation costs and business service through-line processes are becoming a focus of business development, while WebServices is in time, making companies achieve these purposes.
But recently with the slowdown and even in some areas of the global economy, plus the US 911 incident, the company has reduced the investment budget, and the investors are also reduced investment. This is a bad news for the development and adoption of new technologies. We can imagine that the convenience of life, any time, any time, any time, anywhere, will be delayed. The increase in productivity will slow down. So we look forward to the economic recovery, and I look forward to the improvement of information technology to promote productivity.
.NET
.NET's predecessor is Microsoft's DNA (DistributedNetworkarchIture), replaced by .NET during 2000. The .NET adheres to the birth of Microsoft and strategies: Helps customers speed up the market reaction, provide complete, integrated solutions and shortened customers return. These can be reflected in Microsoft's product characteristics. Bill Gates As the Chief Software Architect After the .NET's Vision and Frame Plan, it began to vigorously do the work of market propaganda and research and development, and there was a moment of hosted. .NET uses WebServices as the core, fully supports SOAP, UDDI, and WSDL, and implements the CLR (Common Language Runtime) similar to Java Virtual Machine in the underlying to support .NET underlying library The Visual Basic, C # (Similar to Java Interpretable Programming Language) and ASP, etc. And in the backend supports its database SQL Server and Passport, plus perfect development tools .NET Studio consists of a complete solution. J2EEVS.NET
From 3, in 2002, the GIGA Information Group made a global survey, and 65% of the respondents in the selected platform of "the most influencing your web service strategy" chose J2EE, the remaining 35 % Chose .NET. In fact, many of the respondents have used these two technologies as their future basic application platform. But 75% to 80% in large enterprises have chosen J2EE, while Microsoft. Net occupies favorable positions in small businesses. It can be inferred that the most crazy compensation will appear in the market of medium-sized enterprises.
Justify these two technologies and make choices, not a matter. It is necessary to see the functions that can be implemented in front of them, but also look at the future development direction. However, in general, J2EE has a stronger architecture, pay more attention to enterprise, or gives you more choices and more vendors. And .NET has better development tools, beautiful graphical interfaces, low cost, individual vendors' easy integration and management. For future technological development, both parties will pay more attention to and use partners' power to strengthen and supplement their own platforms. But in the future, the technical decision is still quite different, Microsoft's Chief Technology Architect or CTO Bill Gates is the final decision maker of .NET. J2EE is relatively complex, one of JCPEC (Javacommunity Process'Sexecutive Committee) is this standard decision-making body, and various manufacturers need to submit technical specifications through JSRS (Java Specification Requests), and wait JCP EC. Decide.
So you can say this, if your company pays more attention to the strategy, then choose J2EE; if your business pays more attention to the graphical interface and specific tactics, .net first rushed.
(Source: Communication World)
