are here: Freetutes.com
Analysis and Design
Development of Software - Coding Stage/Phase in SDLC
Once the design is complete, most of the major decisions about the system have
been made. The goal of the coding phase is to translate the design of the system
into code in a given programming language. For a given design, the aim of this
phase is to implement the design in the best possible manner. The coding phase
affects both testing and maintenance profoundly. A well written code reduces the
testing and maintenance effort. Since the testing and maintenance cost of software
are much higher than the coding cost, the goal of coding should be to reduce the
testing and maintenance effort. Hence, during coding the focus should be on developing
programs that are easy to write. Simplicity and clarity should be strived for,
during the coding phase.
An important concept that helps the understandability of programs is structured
programming. The goal of structured programming is to arrange the control flow
in the program. That is, program text should be organized as a sequence of statements,
and during execution, the statements are executed in the sequence in the program.
For structured programming, a few single-entry-single-exit constructs should
be used. These constructs includes selection (if-then-else), and iteration (while
- do, repeat - until etc). With these constructs it is possible to construct a
program as sequence of single - entry - single - exit constructs. There are many
methods available for verifying the code. Some methods are static in nature that
is, that is they do not involve execution of the code. Examples of such methods
are data flow analysis, code reading, code reviews, testing (a method that involves
executing the code, which is used very heavily). In the coding phase, the entire
system is not tested together. Rather, the different modules are tested separately.
This testing of modules is called "unit testing".
Consequently, this phase is often referred to as "coding
and unit testing". The output of this phase is the verified and unit
tested code of the different modules.
Page | Contents
| Next Page >>