Describe the use of various tests in the Software development lifecycle

When it comes to the software lifecycle, let's start by reviewing it. A software PRODUCT or software system also has to undergo the gestation, birth, growth, maturity, decline and other stages, generally known as the software lifecycle (software life cycle) Usually, the software lifetime includes: 1, the problem definition;2, feasibility study;3, demand analysis;4, overall total, 5, detailed design, 6, coding and unit testing, 7, comprehensive testing.

Next, look at software testing. From the stage of software testing, the test can be divided into 4 main stages: unit test, integration test, System test, acceptance test. This is a process of testing from small to large and gradual.

From a feature-based perspective:

　　1, unit Testing This step is mainly for developers in the development process, the program internal functions, classes, variables and so on the correctness of the test. For example, a function needs to insert some important data into the database. After you have written this function, test it to verify that: 1) The function correctly brings out the data variables that need to be inserted into the database.　　2) The data that is brought out can be inserted correctly into the database to be inserted.　　2, functional testing as the name implies is the product of the various functions to verify, according to the functional test cases, test-by-item, check whether the product meets the user requirements of the function.　　In a project, there are many functions, each function has many methods, we can not determine the correctness of the unit test, so we need a more detailed functional testing process. 3, Integration test integration test is based on unit testing, all modules according to detailed design requirements of the assembly into subsystems or systems, for integration testing.　　Integration testing focuses on the correctness of the interface between modules and the overall functionality after integration.　　Once the unit tests for each function or function module have been completed, it is necessary to test whether the overall data flow between these functions or modules is correct.　 4, scene test through the use of the scene to the system's function points or business process description, thereby improving the test effect of a method.   Why does the scenario approach describe the whole event so clearly? Because, today's system is basically the event to trigger the control process. Such as: we apply for a project, we need to submit the approval documents, and then by the department manager for approval, after approval by the general manager to final approval, if the department manager audit does not pass, the direct return. The scenario is formed when each event is triggered. The event flow is formed by the different triggering sequences and processing results of the same event.　　This series of processes we use the scene method can be clearly described clearly. 5, System testing system testing is to be integrated testing software, as a part of the computer system, and other parts of the systems, in the actual operating environment of the computer system to carry out a series of rigorous and effective testing to discover software potential problems, to ensure the normal operation of the system. The purpose of the system testing is to verify whether the final software system meets the user's requirements.　　  Based on non-functional angle: 1, pressure test pressure test is the system of continuous pressure test, by determining a system bottleneck or not receive the performance points, to obtain the system can provide the most service level of testing.　　We usually browse the Web process, the Web site under a lot of load, when the response of the system will degenerate or fail. 2. Regression test regression test refers to re-testing the previous test to ensure the correctness of the modification after the change.　　In theory, a new version of the software will require regression testing to verify that the errors previously discovered and repaired are re-emerging on the new software version. The goal of regression testing is to verify that a previousBut the bugs that have been fixed are no longer re-emerging.　　It is generally referred to as a re-testing of a defect that is known to have been corrected again around the time it originally appeared.　　　　3. The safety test examines the product to verify that the product complies with the safety requirements definition and the product quality standards. 1) Improve the safety and quality of IT products, 2). Try to find a security issue before release to fix the cost; 3) measure security.　　4) Verify that the protection mechanism installed in the system can protect the system in practice, so that it will not be invaded by              , without interference from various factors. 4. Accessibility testing is a test of the possibility of using software for people with varying degrees of accessibility.　　Simply put, it is the test software can be blind, no mouse, presbyopia, color blindness and other disabled persons or some people with disabilities normal use, which also contains a normal person in some cases of temporary obstacles in the case of regular use, such as the arms of infants. Testing software for the accessibility of people with disabilities, whether all pages and components can be read out by a specific read software, whether full keyboard operation is supported, etc. 5. The Compatibility Test compatibility test verifies how dependent the software is on the environment it relies on, including how dependent it is on the hardware platform and how dependent it is on the software platform.　　That is, the portability of the software that is usually said. The primary purpose of the compatibility test is to be compatible with third-party software to ensure that third-party software is functioning properly and that users are unaffected. Because of the variety of application software and system software has been to a large extent, and can be expected to continue to explode at the rate of growth, data sharing between software and system resource sharing becomes a problem, which is the meaning of the compatibility test. Although compatibility testing does not guarantee full quality, compatibility testing is a necessary step for a project.

Describe the use of various tests in the software development life cycle