The life cycle of software

The software life cycle mainly includes the following stages: (1) Planning phase (System analysis and Software definition) (2) Requirements analysis phase (3) Software design phase (4) Coding phase (software implementation) (5) Software integration phase (6) test phase (7) Software acceptance and delivery (8) software use and maintenance

The following is a detailed description of the main elements of each phase of the software lifecycle:

(1) Planning stage. This stage mainly carries on the definition of the software target, and carries on the feasibility research to the software development and the use.

(2) Requirements analysis phase. This stage is primarily for developers to communicate with users in depth to determine what the target system should be capable of. This stage needs to write a written requirement analysis document, and obtain the confirmation of the supply and demand sides.

(3) Software design phase. Design the software development according to the requirement analysis document. Includes overview design and detailed design. Summary design is to transform the requirements into functional modules, detailed design is the implementation of the various modules described in detail, may include the algorithm, data structure, flowchart detailed description. This stage should produce the summary design book and the detailed design book two kinds of documents.

(4) Coding phase. Design the program code and database according to the content of the detailed design book. With the above three stages of bedding, this step of the program implementation will be much easier.

(5) Software integration. The various modules implemented by different programmers are integrated together to form a computer software with complete business functions.

(6) test phase. The testing phase does not have to wait until the end of the software integration phase, and can begin as early as the coding phase, and continues to software delivery. This stage includes: unit test, integration test, System test, acceptance test, alpha test (by a user in the development environment of the test, also can be a user within the development unit in the simulated actual operating environment of the controlled test, alpha test can not be done by programmers or testers), Beta testing (a test performed by multiple users of the software in the context of the actual use of one or more users is not done by a programmer or a tester).

(7) Software acceptance and delivery. After the software is completed and tested, the SOFTWARE PRODUCT is delivered by the developer to the user and the acceptance test is performed before acceptance.

(8) Software operation and maintenance. Software is formally put into use, the developer should maintain the software, to meet the needs of users. The methods of maintenance include: corrective maintenance, adaptive maintenance, perfect maintenance, preventive maintenance.

The life cycle of software