2022 system integration project management engineer examination knowledge points: software development model

Many candidates are preparing for the exam 2022 System integration project management engineer examination , I have arranged for you 2022 Knowledge points of system integration project management engineer examination ： Software development model , For everyone to prepare for the exam and review .

Software development model

For the development model knowledge points , To master the concept of software life cycle 、 Characteristics and applications of various development models . The main development models examined include waterfall model 、 Spiral model 、 Iterative model （RUP）、V Model 、 Agile methods, etc .

（1） Waterfall model . Waterfall model is also called life cycle method , Is the most commonly used development model in structured methods , It divides the process of software development into software planning 、 Demand analysis 、 software design 、 Program code 、 There are six stages of software testing and operation and maintenance , It stipulates that they are from top to bottom 、 A fixed order of connection , It's like a waterfall , Step by step . characteristic ： Accept the results from the previous development activity as the input of this activity ; Use this input , What should be done to implement this activity .

（2） Spiral model . Spiral model combines waterfall model and rapid prototyping model , Combining the advantages of both , And added risk analysis . It is based on prototypes , Rotate from inside to outside along the spiral , Every revolution has to be planned 、 risk analysis 、 Implement engineering and customer evaluation activities , And develop a new version of the prototype . Spiral model emphasizes risk analysis , It is especially suitable for large and complex 、 High risk systems .

（3） Iterative model ： Iterations include generating product releases （ Stable 、 Executable product version ） All development activities for and all other peripheral elements necessary to use the release . therefore , In a way , Development iteration is a complete process through all work processes ：（ At least ） Requirements workflow 、 Analyze design workflow 、 Implement workflow and test workflow . In an iterative model , Every iteration produces a product that can be released , This product is a subset of the final product . Iterative model is applicable to projects that cannot completely define all requirements of products in advance 、 Software development planning multi-phase development . In modern development methods , for example XP、RUP etc. , Recommended without exception 、 Advocate adopting iterative models that can significantly reduce risks . Iterative model is applicable to projects that cannot completely define all requirements of products in advance 、 Software development planning multi-phase development .

（4）V Model . In the waterfall model and other classical models , Testing is often used as an afterthought , But there are also test centric development models , That's it V Model .V The model claims that testing is not an afterthought act , But a process as important as the development process , As shown in the figure below .

① The main purpose of unit testing is to deal with all kinds of errors that may exist in the coding process , For example, the user input the boundary value error in the validation process .

② The main purpose of integration testing is to solve the problems that may exist in the detailed design , In particular, check the possible errors in the interface between each unit and other program parts .

③ The system test is mainly aimed at the outline design , Check whether the system as a whole operates effectively , For example, whether the expected high performance can be achieved in the product setting .

④ Acceptance tests are usually conducted by business experts or users , To confirm that the product can really meet the business needs of users .

（5） Agile methods . It's a human centered 、 iteration 、 Step by step development method , It is applicable to projects with theout or unable to completely determine requirements and scope at beginning , Or need to deal with a rapidly changing environment , Or the needs and scope are difficult to determine in advance , Or you can define smaller incremental improvements in a way that benefits stakeholders .

Agile methods , Also called adaptive life cycle 、 Or change the driving method .

（6） Prototype model . The prototype model is produced to make up for the deficiency of waterfall model .

The first step in prototyping is to build a rapid prototype , Realize the interaction between customers or future users and the system , After discussing and communicating with users about the prototype , Understand the requirements in order to really grasp what the software product users need is like . After fully understanding , On the basis of the prototype, we can develop the products that satisfy the users . In practice, prototyping is often carried out in the process of requirements analysis and definition .