ch. 91 software engineering tools and environments

Ch. 9 1

Software Engineering Tools and Environments

Ch. 9 2

Outline

• How did the field evolve?• How can tools and environments be

classified and compared?• What are the main categories?• How can tools be integrated?• What motivates new

tools/environments?

Ch. 9 3

Historical evolution

• Dominant factors affecting evolution– technological developments

• made certain tools necessary or possible

– better understanding of software engineering processes

Ch. 9 4

Technological developments—examples—

• Advances in graphical displays and user interfaces– graphical editors– graphical user interfaces (GUIs) – visual languages

• Advances in distributed systems– tools supporting distributed

configuration management and teams (groupware)

Ch. 9 5

Evolution

• Individual tools developed to support single activities (e.g.,compilation, debugging)

Integrated environments, i.e., tools that work together– e.g., environment supporting one

programming languageOpen environments

– tools have public interfaces which allow them to communicate and cooperate with other tools which respect those interfaces

Ch. 9 6

Dimensions for comparison (1)

• Interaction mode– batch-oriented tools– interactive tools

• Level of formality– syntax/semantics of documents

produced

• Dependency on phase of life cycle• Degree of standardization

Ch. 9 7

• Static vs. dynamic• Development tools vs. end-product

components• Single-user vs. multi-user• Single-machine vs. network-aware

Dimensions for comparison (2)

Ch. 9 8

Representative tools:Editors

• Textual or graphical• Can follow a formal syntax, or can

be used for informal text or free-form pictures

• Monolingual (e.g., Java editor) or multilingual

Ch. 9 9

Representative tools:Linkers

• Combine object-code fragments into a larger program– can be monolingual or polylingual

• In a broader sense, tools for linking specification modules, able to perform checking and binding across various specification modules

Ch. 9 10

Representative tools:Interpreters

• Traditionally at the programming language level

• Also at the requirements specification level– requirements animation

• Can be numeric or symbolic

Ch. 9 11

Representative tools:Code generators

• In a general sense, transform a high level description into a lower-level description– a specification into an

implementation

• Practical example– 4th Generation Languages

Ch. 9 12

Representative tools:Debuggers

• May be viewed as special kinds of interpreters where– execution state inspectable– execution mode definable– animation to support program

understanding

Ch. 9 13

Representative tools: Software testing (1)

• Test documentation tools– support bookkeeping of test cases

• forms for test case definition, storage, retrieval

Project Name: Date of test:

Tested function:

Test case description:

Description of results:

Tested module:

Comments:

Ch. 9 14

Representative tools: Software testing (2)

• Tools for test data derivation– e.g., synthesizing data from path

condition

• Tools for test evaluation– e.g., various coverage metrics

• Tools for testing other software qualities

Ch. 9 15

Representative tools:Static analyzers

• Data and flow control analyzers– can point out possible flaws or

suspicious-looking statements• e.g., detecting uninitialized variables

Ch. 9 16

Representative tools:GUI tools

• Graphical User Interfaces are now standard

• Common abstractions include– windows and the desktop metaphor

Pole disks 1 3

2 0 3 0

Ch. 9 17

User-Interface Management Systems

• Provide a set of basic abstractions (windows, menus, scroll bars, etc.) that may be used to customize a variety of interfaces

• Provide a library of run-time routines to be linked to the developed application in order to support input and output– UIMS fall both under the category of

development tools and under the category of end-product components

Ch. 9 18

Run-time dialog component

Dialog development tools

Progr.language run-time support

End user

DeveloperProgr. env.mt

UIMS as development tool and end-product component

Ch. 9 19

SCREEN

First name Last name

Birth date

day

month

year

Person

First name Last name Birth date

Day Month Year

Run-time dialog component

INTERNAL DATA STRUCTURE

Run-time structure of a UIMS

Ch. 9 20

Representative tools:Configuration Management

• Repository• shared database of artifacts

• Version management• versions stored, change history maintained

• Work-space control• check-out into private work-space• check-in into shared work-space

• Product modeling and building• facilities to (re)build products

Ch. 9 21

CVS

1.1 1.2 1.3 1.4

1.1 1.2 1.3

1.2.1.1 1.2.1.2

2.1

2.1 2.2

sequence of revisions

a branch and alater join

Ch. 9 22

make

1. sys : mod1.o mod2.o2. ld mod1.o mod2.o -o sys 3. mod1.o : mod1.c incl.h4. cc -c mod1.c5. mod2.o : mod2.c incl.h6. cc -c mod2.c

aids in building and rebuilding a producthelps keep a system in a consistent state after modifications

Ch. 9 23

Representative tools:Tracking tools

• Used during entire process to maintain information about the process and track that information

• The most important of these are defect-tracking tools– used to store information about

reported defects in the software product and track that information

Ch. 9 24

Representative tools:Reverse and

reengineering• Program understanding systems

– synthesize suitable abstractions from code • e.g., control and data flow graphs or use graphs

– extract cross-references and other kinds of documentation material on the product

• Reverse engineering tools also support the process of making the code and other artifacts consistent with each other

Ch. 9 25

Representative tools:Process support

• Maintain "to do" lists, reminding next activities in the process

• Automate sequences of recurring actions

• Full process support via PSEEs (Process-centered Software Engineering Environments)– driven by a process-modeling

language

Ch. 9 26

Representative tools:Management

• Tools for Gantt and PERT charts– graphical interface– support to analysis

• Cost estimation tools– based on models, such as COCOMO

Ch. 9 27

Tool integration

• Data integration approach– store all process artifacts in a

repository – common data representation for

artifacts that different tools can use to communicate with each other

• Control integration approach– different tools can communicate with

each other through control messages

Ch. 9 28

Forces influencing tool evolution

• To support new technology• To support new software processes• To support a particular method or

methodology