In the practice, the incremental development is not allowed. It is strictly forbidden to reprint this column This paper is reproduced from the Software Engineering Expert Network www.21cmm.com. Do not reprint without CBS license, thank you for the application development of cooperative incremental software development As shown in Figure 1. The incremental development plan in Figure 1 divides the project into four incremental parts, reuse the existing components in some increments, created the top-level architecture in the increment 1, defined three low-layer subsystems, one of which It has been implemented. The realized subsystem contains an reusable component, and the stubs used in the subsystem will be implemented in subsequent increments. Piles are not only placeholders, but it contains an interface specification and function specification, so that the mutual relationship between functions and pile functions is well defined. When completed, the increment 1 is evaluated by the user. As a result of the user feedback, the components in the increment 1 are the conversion of the increment 2. The second subsystem is implemented in the increment 2, instead of the pile in the increment 1. Other existing components are reused in increment 2, by modifying an increase in increment 2. The increased function is defined in increment 2, but it is achieved until the final increment is achieved. The third subsystem implementation begins with increment 3. The third subsystem contains a new component, a reuse component, and a pile. User evaluation of increment 3 results in a change in a component in increment 4. Increment 4 is like all previous increments, which is the accumulation of all work so far, plus some new work. During increment 4, all reserved piles are implemented. As the final increment, increment 4 represents the entire complete system. The processing of the remainder of the system is important for the integration of the design. The correctness of each step is verified, and the sequence of subsequent increments is logically logically logically in the proper execution point. The completeness of each step of incremental design ensures the balance integration of new work progress. Figure 2 shows the progress assignment of incremental development of the project. After the top-level specification, an incremental development plan is established. Normative and Incremental Development Plan changes according to the development experience, quality assay and user feedback after each step. When each step is integrated, the complete definition, design and verification, will be submitted for an independent authentication test. The quality metrics in the certification test (such as failure time, reliability, the number of errors per thousand lines) are the measurement specifications for development process control. If the measured quality meets the establishment of standards, the development will continue. If you do not meet, find out the cause, take action to improve the development process. When the increment 1 delivers the authentication test, the development of the specification of the increment 1 is embedded. If there are multiple development groups, increment 3 can also start parallel at the same time. The incremental development of the expandable system provides user feedback, intelligent control, progress, and budget management control of technology work. Regarding each incremental user feedback is determined whether a correct system is established, the quality metrics in each increment are judging whether or not a system is correctly established. This method also supports product quality and process control.
