Subject: Programming environments
Programming environments
Concept, functions and types
1. Software development activities
In Software Engineering a certain organization is called "life cycle" in
the time of the software development activities. The main activities are the following
:
Analysis
Design
Coding
Integration
Maintenance
The figure represents the so-called "cascade life cycle", where the arrows indicate
the order in which the activities are carried out. This model is in disuse, but is still
being adequate to identify the main activities and the natural order between them.
Analysis of requirements
The needs of the users are studied, it is decided what should be done
] computer application to satisfy them in whole or in part, and a
Requirements Document is generated.
Architecture Design
The Requirements Document is studied and the global structure of the
application is established , decomposing it into parts (modules, subsystems) relatively
independent. A Design Document is generated.
Detailed Design
In this second part of the design activity, the functions of each
module are set, with the detail of its interface. The declaration code (or
specification) of each module is generated.
Coding
The code of each module is developed.
Programming environments – 1
Programming environments
Tests of units
As a complement to the coding, each module or group of modules is
tested separately. In the tests, it is checked whether each module complies with its
detailed design specification.
Integration tests
The complete application is operated, combining all its modules. Se
perform tests to verify that the overall operation complies with
established in the design document.
Validation tests
As a final step of the integration, new tests of the application are performed in
] its set. In this case, the objective is to verify that the product developed
complies with the provisions of the requirements document, and therefore satisfies the
needs of users to the extent provided.
Maintenance phase
There are no differentiated activities from the previous ones. The maintenance of the product
requires redoing some of the initial work, which may correspond to any of the
activities of the previous stages.
Programming environments – 2
Programming environments
2. Software development environments
A software development environment is a combination of tools that
automates or supports at least a large part of the tasks (or phases) of development: requirements analysis
design architecture, detailed design, coding, unit tests,
integration and validation tests, configuration management, maintenance, etc. The
tools must be well integrated, being able to interoperate with each other.
They are formed by the set of instruments (hardware, software, procedures, …)
that facilitate or automate development activities. In the context of this subject
software instruments are basically considered.
• CASE: Computer-Aided Software Engineering
o With this generic term are called software products that support
computing development [19659002] o It would be desirable to automate the whole development, but it is usually automated
only in part
or CASE Products: they are each of the tools or software tools of
development support
• CASE technology supports vertical activities
o Vertical activities are specific to a phase of the life cycle: analysis
of requirements, architecture design, edition and compilation of the code, etc.
• Support is also needed for horizontal activities
o Horizontal activities are the general activities: documentation,
planning, configuration management, etc.
In [194] 59007] a practical vision of what is a development environment is exposed.
Programming environments – 3
Programming environments
3. CASE products in general
CASE products facilitate the organized development of the software applying techniques from
Software Engineering. In a broad sense we can include in CASE technology all
the variety of tools applicable in software development: analysis tools
and design; editors of code, documents, diagrams, etc .; compilers and editors of
executable code (linkers); debuggers; consistency analyzers; tools for
obtaining metrics; code or documentation generators; etc., etc.
Due to that huge variety of products, various attempts have been made to
classify them. A point of view for its classification is the level of functions performed by a
particular product. In [3] (Table I) the following terminology is suggested for functional levels
:
• Service (service): automatically performs a certain operation (atomic or
unitary).
Example: compilation of a program
• Tool: provides the services needed to support a given task
(what a member of the development team does at a given time
).
Example: source code edition.
• Workbench: supports all the corresponding activities
to a professional role or profile of one of the members of the development team.
also called "tool" (tool)
Example: "tool" CASE of analysis and design (OO, UML, …)
• Environment or factory (environment, factory): it supports the whole process of development.
Sometimes it is also called "workbench" [19] 659002] Programming environments – 4
Programming environments
4. Programming environment
The activities best supported by development tools are usually the central
: coding and unit testing. The set of tools that support
these activities constitute what is called a programming environment. Sometimes they
use the abbreviations IDE (Integrated Development Environment) to designate these environments,
although they are not a complete development environment, but only a part of it.
• Following the previous terminology, of levels functional, is the workbench of the
programmer
• It supports the activities of the coding phase (preparation of the code and
unit test)
• The same products are also used for the design detailed and for the
integration tests.
• It is situated, therefore, in the central part of the development cycle
Analysis
Design
Coding
Detailed design
Coding
Unit Test
Tests of
Integration
Integration
Maintenance
Programming Environments – 5
Programming Environments
5. Functions of a Programming Environment
As has been said, the mission of a Programming Environment is to support the preparation
of programs, that is, to coding and testing activities.
• Tasks Essentials of the coding phase are:
or Edition (creation and modification) of the source code
or Process / execution of the program
– Direct interpretation (source code)
– Compilation (machine code) – assembly – execution
– Compilation (intermediate code) – interpretation
• Other functions:
o Browse (browse) the source code
or Analyze consistency, quality, etc.
or Execute in mode debug
o Automatic execution of tests
or Version control
o Generate documentation, reform code
or … and many more …
Programming environments – 6
Programming environments
6. Types of Programming Environments
A programming environment can be conceived and organized in very different ways
. Some of them are mentioned below.
• In the early stages of computing, program preparation was carried out
through a chain of operations such as the one shown in the figure for
a language processed by compiler. Each of the tools had
to be manually invoked separately. Under these conditions can not be spoken
properly a programming environment
Editor
Compiler
Editor
Debugger
P. source
P. object
Bookstore
P. executable
Result
o The editor is a simple text editor
o The compiler translates each source code file into object code
o The editor (linker / builder / loader) combines several object files for generate
an executable file
o The debugger handles information in terms of machine language
• A programming environment itself combines tools such as these,
improved and better integrated. It is sometimes referred to by IDE (Integrated
Development Environment).
IDE
Reform
Compiler
Editor
Debugger
Tests
References
.. . etc. …
• The components whose evolution has been most apparent are those that perform the
interaction with the user:
o The editor is no longer a simple text editor, but has a clear orientation [19659002] to the programming language used (recognizes and handles certain syntactic elements
)
Programming environments – 7
Programming environments
o The debugger does not present information in terms of the machine language, but [19659002] of the source language
o The editor is well integrated with the other tools (it is positioned
directly in the source code points where there are errors in
compilation, or that are running with the debugger at a given moment
• It is not easy to establish a classification within the variety of environments of
existing programming. [1] The following classes
of environments were described at some point [1] , not excluding, using an essentially pragmatic approach:
o Language-centric environments
o Structure-oriented environments
o Tool collection environments
Other classifications are presented in [4] and [5] based on more or less formal
criteria.
6.1 Environments centered on a language
Present the following general characteristics:
.
from Nettech Post http://bit.ly/2sbKeXg
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