CORBA-based distributed programming Advanced Corba Distributed Programming
introduction
In recent years, with the increasing maturation of Internet technology, public and commercial companies are enjoying the high-quality digital life brought by high speed and low-cost network information transmission. However, due to the continuous expansion of network size and the rapid speed of computer hardware and software technology, it has brought great challenges to the traditional application software system.
First, in enterprise applications, hardware system integrators are based on performance, price, service, etc., usually integrate hardware devices, operating systems, database platforms, etc. from different manufacturers, etc. in the same system, resulting in Isomerism has brought serious problems with interoperability, compatibility, and smooth upgrade capabilities for application software.
In addition, as the network-based business is increasing, the distributed application of traditional client / server (C / S) mode is increasingly displayed in the limitations of operational efficiency, system network security, and system upgrade capabilities.
In order to solve the interconnection of different hardware devices and software systems in the distributed computing environment (DCE, DISTRIBUTED Computing Environment), enhance interoperability between network software, solve the shortcomings in traditional distributed computing models, etc., object management organization (OMG) A common object requesting agency architecture (CORBA) is proposed to enhance the interoperability between software systems to make the construction flexible distributed application system possible.
It is based on the development and maturity of object-oriented technology, the general application of customer / server software system model and integration of existing systems, and promoting the maturation and development of CORBA technology. As the core of object-oriented system, CORBA has brought a true interconnection for today's network computing environment.
Summary
The paper mainly introduces the basic principles and overall frameworks of CORBA (public object request agency structure), and the basic method of applying CORBA intermediate parts for enterprise-class distributed applications.
In response to the continuous development of new data services, growing data volumes and continuously improved real-time requirements, China Mobile BOSS system adopts CORBA distribution for the considering of interoperability between software systems, constructive intertility distributed application systems. Multi-layer system architecture achieves the original intention of integration, centralized, real-time, and three-story platform.
In order to meet the requirements of Jiangsu Netcom integrated data network integrated business billing and management system and the BOSS system, the interface of LCMIS system and Jiadu company and Jiadu company is preparing to architecture on CORBA's service system. CORBA-based chat software implements communication between different middleware (CORBA and TUXEDO), making the integration of LICMS and Hummer systems, and lay a technical foundation for the smooth integration of the two systems.
Chapter 1 CORBA Introduction
1.1 CORBA Overview
CORBA (The Common Object Request Broker Architecture: General Object Request Agent Structure) is a distributed object-oriented application architecture specification. It is proposed by the OMG research group in the late 1980s. It is gradually improved in the 1990s, and the formation is now common by the software industry. Approved Standards - Corba / IIOP Specification 2.3. Corba's developer OMG initially constructed from 3CM, American Airlines, Canon, Data General, Hewlett-Packard, Philips, Sun and Unisys, formed in 1989, specializing in research and industry standards for public software platforms, currently More than 800 member units join OMG.
CORBA is a new technology that has developed in the case of rapidly developing software and hardware resources. It allows the distributed application to complete communication, regardless of what vendors are produced, as long as the CORBA standard can communicate with each other. CORBA 1.1 is proposed in 1991, and also proposes interface definition language interface definition language, id1, and allows client / server objects to communicate in a particular ORB (Object Request Agent) implementation. The CORBA 2.0 standard proposed and adopted in 1994 truly realized interoperability between different manufacturers. CORBA is an industrial standard funded by object management organization (ORG) funding in distributed object projects. Corba is just a standard, which is introduced to achieve distributed calculations. To illustrate what the CORBA is in the distribution calculation, we will explain from it in comparison with several other distribution computing technologies.
Unlike pastly-oriented RPC (Remote Procedure Call), CORBA is based on object-oriented technology, which can solve interoperability between remote objects. Microsoft's DCOM (Distributed Component Object Model) is also solving this problem, but it is based on a Windows operating system. Although the DCOM has implemented in other operating systems such as Sun Solaris, Digital UNIX, IBM MVS when writing. But there is no doubt that it will only be better on Microsoft's operating system. Only CORBA is a truly cross-platform, platform independence is one of the original intentions of CORBA. Another technique for platform-independent is Java RMI (Remote Method Invocation), but it can only be implemented in Java. CORBA is different from this, which can be used as a language-defined language that is called IDL (Interface Definition Language), that is, any language can make CORBA components, while CORBA components can be used in any language.
Therefore, it is possible to understand the language-independent object interoperability model in CORBA: CORBA. That is, CORBA design is independent of the platform and language, so CORBA can run on any platform, which can be positioned anywhere in the network, and can use any language with an IDL (Interface Definition Language).
1.2 CORBA development and evolution
After nearly ten years of development, CORBA has gradually been mature, and successfully applied in many large software systems in my country, thereby producing a lot of demand for software developers who grasp CORBA technology. Here, we have organized this lecture at the request of the readers. This series introduces the basic idea, architecture, and development of CORBA, and the design and development of CORBA applications. I hope to help the majority of software development, designers, open ideas, and deepen the understanding of CORBA, and then truly master this technology. And can develop a more powerful software system in actual work, more efficient and rapidly developing a stronger software system, and ultimately promoting the booming of my country's software career.
CORBA development process
1. Object Management Organization (OMG)
OMG was established in 1989, as a non-profit organization, focusing on the development of advanced technology, commercially feasible and independent of the manufacturer's software interconnection, promoting object-oriented model technology, enhancing software Portability, Reusability and Interoperability.
At the beginning of the organization, members include Unisys, Sun, Cannon, Hewlett-Packard, Philips, etc., Which have reputable hardware and software in the industry, and currently has more than 800 members.
2. The main version of CORBA
● In November 1990, OMG issued the "Object Management System Guide" and preliminantly clarified the idea of CORBA;
● October 1991, OMG launches version 1.0, which defines the interface definition language (IDL), object management model, and content based on dynamic requesting API and interface warehouse;
● In December 1991, OMG launched the CORBA version 1.1, on the basis of clarifying the two-meaning in version 1.0, introduced the concept of object adapter;
● In August 1996, OMG based on the previous upgrade version, completed the development of version 2.0, the importance of this version is the introduction of the object request Agent Agreement (IIOP, Internet Inter-ORB Protocol) to achieve different manufacturers. ORB true interoperability;
● In September 1998, OMG issued the CORBA version 2.3, which added asynchronous real-time transmission, service quality specification, and so on supporting CORBA objects. Currently, middleware manufacturers who announced support for Corba 2.3 specifications include the famous CORBA product manufacturer such as Inprise (Borland), Iona, Bea System.
