(Done) 2. Design, Testing and IDEs Flashcards
1
Q
What are structure diagrams
A
- Diagrams that show the smaller tasks of a larger programs
2
Q
Features of structure diagrams
A
- The programs you want to write is split up into manageable modules
- Each of those modules is decomposed even smaller modules and eventually into modules that perform individual tasks
3
Q
Advantages of structure diagrams (5)
A
- Easier to write code to carry out individual tasks
- Makes cooperation easier as each module can be written individually
- Its easier to test as each module is independent
- Each module can be updated independently
- able to reuse the modules in the future
4
Q
Define a program being easy to maintain
A
- It is easy for other programmers to add onto or repair the program
5
Q
What features of a code can improve the maintainability
A
- Comments explaining key features of the program
- Indentation separating different segments of the program
- Accurate naming of Variables, sub programs and parameters
- Using sub programs
6
Q
What is the purpose of defensive design
A
- To ensure a program functions properly
7
Q
Define program misuse
A
- The user doing things the programmer does not expect them to do
8
Q
Methods of defensive design
A
- Anticipating how users might misuse their program and attempt to prevent it
- Ensure their code is well maintained
- Reduce the number of errors in their code through testing
9
Q
Define input validation
A
- Checking if data meets certain criteria before passing it into the program
10
Q
Why is input validation used
A
- To prevent accidental or intentional misuse of a program when entering data
11
Q
Types of Input validation
A
- Range check
- Presence check
- Format check
- Look-up table
- Length check
12
Q
What is a range check
A
- Checks whether the data is within a specified range
13
Q
What is a presence check
A
- Checks whether data has actually been entered
14
Q
What is a format check
A
- Checks the data has the correct format (e.g. a date)
15
Q
What is a look-up table
A
- Checks the data against a table of acceptable values
16
Q
What is a length check
A
- Checks the data is the correct length
17
Q
What does authentication do
A
- Confirms the identity of a user before they’re allowed to access certain pieces of data or features in the program (e.g. passwords)
18
Q
Common ways to increase the security of a password based system
A
- Force users to use strong passwords and get them to change them regularly
- Limit the number of failed authentication attempts before an account is lost
- Ask for a random selection of characters from the password on each authentication
19
Q
Types of errors
A
- Syntax errors
- Logic errors
20
Q
Define syntax errors
A
- When the compiler or interpreter doesn’t understand something due to and error in language rules or grammar
21
Q
Define logic errors
A
- When the compiler or interpreter is able to run the program, but the program does something unexpected
22
Q
How are syntax errors diagnosed
A
- They’ll be unable to translate the source code and a syntax error (with it’s location) will be returned
23
Q
How are logic errors diagnosed
A
- Compilers and interpreters will not detect them
- Diagnosed by systematically testing the program
24
Q
Two main types of testing
A
- Iterative testing
- Final testing
25
Define iterative testing
- The program is tested while it is being developed
26
Define final testing
- The program is tested at the end of the development process
27
What will be contained within a test plan
- The outline of exactly what you are going to test and how you are going to test it
28
Types of test data
- Normal data
- Boundary data
- Invalid data
- Erroneous data
29
Define normal data
- Things that a user is likely to put in a program
30
Define boundary data
- Values at the limit of what the program should be able to handle
31
Define invalid data
- Inputs with a correct data type that should be rejected by the program
32
Define erroneous data
- Inputs with an incorrect data type that should be rejected by the program
33
Features of high-level languages (6)
- One instruction is many machine code instructions
- Same code will work for many different machines and processors
- The programmer can easily store data without knowing about the memory structure
- Code is easy to read, understand and modify
- Must be translated before a computer is able to understand it
- Not much control over what the CPU actually does so programs will be less memory efficient and slower
34
Features of low-level languages (6)
- One instruction of assembly code is usually one instruction of machine code
- Usually written for one type of machine or processor, won't work on any others
- The programmer needs to know about the internal structure of the CPU and how it manages memory
- Code is difficult to read, understand and modify
- Machine code can be executed directly without a translator
- Control of what the CPU does so programs are more memory efficient and faster
35
Features of a compiler (4)
- Translates all of the source code at the same time and creates an executable file (exe)
- Only needed once to create an exe
- Returns a list of errors for the entire program once compiling is complete
- Once compiled the program runs quickly but compiling can take a long time
36
Features of an interpreter (4)
- Translates and runs the source code one instruction at a time
- Needed every time you want to run the program
- Returns the first error it finds and then stops the program
- Program will run more slowly because the code is being translated as the program is running
37
Define IDE
- A piece of software that provides features to help a programmer develop their program
38
Parts of an IDE (6)
- Code editor
- Run-time environment
- Explorer window
- output window
- Error diagnostic and debugging tools
- Breakpoints
39
Function of a code editor
- Where the code is written, usually has line numbering and auto-color coding
40
Function of a run-time environment
- Allows the code to be run quickly via a start or run button
41
Function of a explorer window
- Helps navigate through programs
42
Function of an output window
- To show the output from a program when it is run
43
Function of error diagnostic and debugging tools
- To help find and fix errors in a program
44
Function of breakpoints
- Stop the program of certain lines so you can gather information like value of variables whilst the program is running
45
Features of an IDE
- Translator
- Auto-documentation
- GUI builder
46
Features of a translator
- Compiler, interpreter or both
- Allows the source code to be interpreted by the computer
47
Features of Auto-documentation
- Helps with maintenance
- Can extract certain features of a program, variable names, sub program names and comments stored in a separate document
48
Features of a GUI builder
- Helps the programmer design a user interface by building it graphically rather than having to design it using source code
