Chapter 9 Compatibility TestingWord格式.docx

1、Configuration Testing, you learned about hardware configuration testing and how to assure that software works properly with the hardware it was designed to run on and connect with. This chapter deals with a similar area of interaction testingchecking that your software operates correctly with other

2、software.Testing whether one program plays well with others has become increasingly important as consumers demand the ability to share data among programs of different types and from different vendors and take advantage of the ability to run multiple programs at once.It used to be that a program cou

3、ld be developed as a standalone application. It would be run in a known, understood, benign environment, isolated from anything that could corrupt it. Today, that program likely needs to import and export data to other programs, run with different operating systems and Web browsers, and interoperate

4、 with other software being run simultaneously on the same hardware. The job of software compatibility testing is to make sure that this interaction works as users would expect.The highlights of this chapter include What it means for software to be compatible How standards define compatibility What p

5、latforms are and what they mean for compatibility Why being able to transfer data among software applications is the key to compatibilityCompatibility Testing OverviewSoftware compatibility testing means checking that your software interacts with and shares information correctly with other software.

6、 This interaction could occur between two programs simultaneously running on the same computer or even on different computers connected through the Internet thousands of miles apart. The interaction could also be as simple as saving data to a floppy disk and hand-carrying it to another computer acro

7、ss the room.Examples of compatible software are Cutting text from a web page and pasting it into a document opened in your word processor Saving accounting data from one spreadsheet program and then loading it into a completely different spreadsheet program Having photograph touchup software work co

8、rrectly on different versions of the same operating system Having your word processor load in the names and addresses from your contact management program and print out personalized invitations and envelopes Upgrading to a new database program and having all your existing databases load in and work

9、just as they did with the old programWhat compatibility means for your software depends on what your team decides to specify and what levels of compatibility are required by the system that your software will run on. Software for a standalone medical device that runs its own operating system, stores

10、 its data on its own memory cartridges, and doesnt connect to any other device would have no compatibility considerations. However, the fifth version of a word processor （see Figure 9.1） that reads and writes different files from other word processors, allows multiuser editing over the Internet, and

11、 supports inclusion of embedded pictures and spreadsheets from various applications has a multitude of compatibility considerations.Figure 9.1. Compatibility across different software applications can quickly become very complicated.View full size imageIf youre assigned the task of performing softwa

12、re compatibility testing on a new piece of software, youll need to get the answers to a few questions: What other platforms （operating system, web browser, or other operating environment） and other application software is your software designed to be compatible with? If the software youre testing is

13、 a platform, what applications are designed to run under it? What compatibility standards or guidelines should be followed that define how your software should interact with other software? What types of data will your software use to interact and share information with other platforms and software?

14、Gaining the answers to these questions is basic static testingboth black-box and white-box. It involves thoroughly analyzing the specification for the product and any supporting specifications. It could also entail discussions with the programmers and possibly close review of the code to assure that

15、 all links to and from your software are identified. The rest of this chapter discusses these questions in more detail.Platform and Application VersionsSelecting the target platforms or the compatible applications is really a program management or a marketing task. Someone whos very familiar with th

16、e customer base will decide whether your software is to be designed for a specific operating system, web browser, or some other platform. Theyll also identify the version or versions that the software needs to be compatible with. For example, youve probably seen notices such as these on software pac

17、kages or startup screens:Works best with AOL 9.0Requires Windows XP or greaterFor use with Linux 2.6.10This information is part of the specification and tells the development and test teams what theyre aiming for. Each platform has its own development criteria and its important, from a project manag

18、ement standpoint, to make this platform list as small as possible but still fill the customers needs.Backward and Forward CompatibilityTwo terms youll hear regarding compatibility testing are backward compatible and forward compatible. If something is backward compatible, it will work with previous

19、versions of the software. If something is forward compatible, it will work with future versions of the software.The simplest demonstration of backward and forward compatibility is with a .txt or text file. As shown in Figure 9.2, a text file created using Notepad 98 running under Windows 98 is backw

20、ard compatible all the way back to MS-DOS 1.0. Its also forward compatible to Windows XP service pack 2 and likely will be beyond that.Figure 9.2. Backward and forward compatibility define what versions will work with your software or data files.NOTEIts not a requirement that all software or files b

21、e backward or forward compatible. Thats a product feature decision your software designers need to make. You should, though, provide input on how much testing will be required to check forward and backward compatibility for the software.The Impact of Testing Multiple VersionsTesting that multiple ve

22、rsions of platforms and software applications work properly with each other can be a huge task. Consider the situation of having to compatibility test a new version of a popular operating system. The programmers have made numerous bug fixes and performance improvements and have added many new featur

23、es to the code. There could be tens or hundreds of thousands of existing programs for the current versions of the OS. The projects goal is to be 100 percent compatible with them. See Figure 9.3.Figure 9.3. If you compatibility test a new platform, you must check that existing software applications w

24、ork correctly with it.This is a big job, but its just another example of how equivalence partitioning can be applied to reduce the amount of work.To begin the task of compatibility testing, you need to equivalence partition all the possible software combinations into the smallest, effective set that

25、 verifies that your software interacts properly with other software.In short, you cant test all the thousands of software programs on your operating system, so you need to decide which ones are the most important to test. The key word is important. The criteria that might go into deciding what progr

26、ams to choose could be Popularity. Use sales data to select the top 100 or 1,000 most popular programs. Age. You might want to select programs and versions that are less than three years old. Type. Break the software world into types such as painting, writing, accounting, databases, communications,

27、and so on. Select software from each category for testing. Manufacturer. Another criteria would be to pick software based on the company that created it.Just as in hardware configuration testing, there is no right textbook answer. You and your team will need to decide what matters most and then use

28、that criteria to create equivalence partitions of the software you need to test with.The previous example dealt with compatibility testing a new operating system platform. The same issues apply to testing a new application （see Figure 9.4）. You need to decide what platform versions you should test y

29、our software on and what other software applications you should test your software with.Figure 9.4. Compatibility testing a new application may require you to test it on multiple platforms and with multiple applications.Standards and GuidelinesSo far in this chapter youve learned about selecting the

30、 software that youll compatibility test with your program. Now, its time to look at how youll approach the actual testing. Your first stop should be researching the existing standards and guidelines that might apply to your software or the platform.There are really two levels of these requirements:

31、high-level and low-level. It may be a misnomer to refer to them as high and low, but in a sense, thats really what they are. High-level standards are the ones that guide your products general operation, its look and feel, its supported features, and so on. Low-level standards are the nitty-gritty details, such as the file formats and the network communications protocols. Both are important and both need to be tested to assure compatibility.High-Level Standards and GuidelinesWill your software run under Wind