First, the historical origin of component technology
In the 1968 NATO Software Engineering Conference, MCLLROY put forward the idea of "software assembly production line" in the "Software Components" in the submission of the conference. Since then, the components technology implements software multiplexing, using "granted wood" to produce software, becoming a long-term dream of software developers. Software multiplexing refers to the process of repeating the process of software designed for multiplex purposes. For software development, software reuse includes: early function multiplexing, object-oriented words
The multiplexing of the class, and the components of the complete software system in the Internet age.
Effective software multiplexing can improve the efficiency and quality of software development. The software multiplexing based on component multiplexing will bring great value, "Software Reuse" pointed out that many companies have convinced that the achievements made by multiple companies make persistently, management can look forward to obtaining the following advantages.
1) Place the market time: Reduce the original 1/2 to 1/5;
2) Defect density: Reduce 1/5 to 1/10;
3) Maintenance cost: Reduce 1/5 to 1/10;
4) Overall software development costs: Reduce approximately 15%, long-term projects can be reduced as 75%.
Therefore, component technology has always been considered to solve the practical way of software crisis. In the past few decades, although the mainstream thoughts of software development have been erased, the software industry has not given an attempt to abandon component technology.
At the end of the 190s, in the early 1980s, the structured software development idea dominated, and the multiplexed complex was the function multiplexing and module multiplexing. The function adapts to different application requirements by parameters, and the package module is also connected and assembled through the interface specification description. However, due to structural existence, the multiplexing ability of the function level is limited, and the result is that the system structure is confusing, the efficiency is low, and the software ingredient is reused. Function multiplexing and module multiplexing do not solve the crisis of software engineering.
In the L80, the object-oriented software development thought rapidly, through the package, inheritance and application, the object-oriented software development successfully implemented the code level multiplexed. Category and encapsulation, implement data abstraction and information hidden, inheritance, and improve code reuse. Object-oriented technology is recognized as current mainstream technology. However, the object-oriented multiplexing is not out of the code level reuse, and since the multiplexed particles are low, the potential of the reuse in software development is far from being played. Class multiplexing has not resolved the crisis of software engineering.
Second, the technology of components in the Internet
The Internet Application Age has not only increased the complexity of application requirements and software. Component technology has advanced in the Internet era, and has been aware of software crisis in the Internet.
l Wub-facing technology to achieve higher levels of abstraction
Component technology is packaged for a set of groups, and represents a specific service of one or more functions, and provides users with multiple interfaces. The entire component hides the specific implementation and serves only using the interface. Thus, at different levels, both the components can combine a plurality of logical logic of the bottom layer into new components with large particle size, even directly to a system, enable the reuse of the module from the code level, object level, and architecture level to The system level may be implemented, so that the software is like hardware, the dream that can be equipped with a fixed system is achieved.
l The components technical standards are mature
At present, the mainstream software component technical standards are: Microsoft proposed COM / COM , Sun Proposed JavaBean / EJB, OMG proposed CORBA. They provide portability, isomeric realization environment and robust platform for the development of application software, ending the development of the development language chaos in the object, solving the problem of software multiplexing in communication, interoperability, etc. .
Third, my country's software industry research on component technology
l Beijing University Software Engineering Institute
Beijing University Software Engineering Research Institute is an academic institution focused on research and practice in software engineering and its related fields. It was established in the 1983 Software Engineering Teaching and Research, and officially listed in 1999 to become a professional research institute of Peking University. In recent years, under the leadership of the company's Yang Fuqing academician, the software reuse and software component technology has been conducted in-depth research. The results represent the bluebird project, after the "seven-five", "eight five" "nine five". Bluebird Project has achieved results in software reuse and component technology.
l Chinese Academy of Sciences Software Research Institute
The Software Engineering Technology Research Center of the Chinese Academy of Sciences, under the leaders of Dr. Feng Yulin, chief researcher, in depth, fruitful results. Among them, the information basic software core platform for the results of knowledge innovation projects is representative.
l Shanghai Puyuan
Puyuan is one of the earliest manufacturers in China, and is also a special manufacturer in China only providing a realized Internet application base platform for components. Puyuan created a new Internet-related technology with advanced component multiplexing techniques and visual development technologies, created a set of application base platforms with internationally leading components ---- EOS.
l Internet laboratory
The Internet Lab is the famous IT research institution in my country. It has long been engaged in component technology and software industries. It issued a "component-oriented Internet application foundation platform research report on January 16, 2004" is currently more detailed in China. Technical research professional report.
