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Abstract

The field of software visualization (SV) investigates approaches and techniques for static and dynamic graphical representations of algorithms, programs (code), and processed data. SV is concerned primarily with the analysis of programs and their development. The goal is to improve our understanding of inherently invisible and intangible software, particularly when dealing with large information spaces that characterize domains like software maintenance, reverse engineering, and collaborative development. The main challenge is to find effective mappings from different software aspects to graphical representations using visual metaphors. This paper provides an overview of the SV research, describes current research directions, and includes an extensive list of recommended readings.
Innovations Syst Softw Eng (2005) 1: 221–230
DOI 10.1007/s11334-005-0019-8
STATE OF THE ART
Denis Graˇcanin · Krešimir Matkovi´c
Mohamed Eltoweissy
Software visualization
Received: 1 May 2005/ Accepted: 18 June 2005 / Published online: 29 July 2005
© Springer-Verlag 2005
Abstract The field of software visualization (SV) investi-
gates approaches and techniques for static and dynamic graph-
ical representations of algorithms, programs (code), and
processed data. SV is concerned primarily with the analysis of
programs and their development. The goal is to improve our
understanding of inherently invisible and intangible software,
particularly when dealing with large information spaces that
characterize domains like software maintenance, reverse eng-
ineering, and collaborative development. The main challenge
is to find effective mappings from different software aspects
to graphical representations using visual metaphors. This
paper provides an overview of the SV research, describes
current research directions, and includes an extensive list of
recommended readings.
1 Introduction
Software visualization (SV) can be defined as a discipline
that makes use of various forms of imagery to provide insight
D. Graˇcanin (
B
)
Department of Computer Science,
Virginia Tech, 660 McBryde Hall,
Blacksburg, VA 24061, USA
E-mail: gracanin@vt.edu
Tel.: +1-540-2312060
Fax: +1-540-2316075
K. Matkovi´c
VRVis Research Center for Virtual Reality and Visualization, Ltd.,
DonauCity-Strasse 1,
1220 Vienna, Austria
E-mail: Matkovic@VRVis.at
Tel.: +43-1-2050130100
Fax: +43-1-2050130900
M. Eltoweissy
Bradley Department of Electrical and Computer Engineering,
Virginia Tech, 7054 Haycock Road,
Falls Church, VA 22043, USA
E-mail: toweissy@vt.edu
Tel.: +1-703-5388374
Fax: +1-703-5388348
and understanding and to reduce complexity of the exist-
ing software system under consideration” [60]. SV refers to
the visualization of computer programs and algorithms [108]
and attempts to give physical shape to shapeless or intangible
software that “disappears into disks.” The goal is to provide
better comprehension of software artifacts [5].
The use of SV raises the questions [2]: What can be visu-
alized? How? For what reasons? The effectiveness of SV is
also a basic question. Research over the years has envisioned
different aspects of source code, the code itself, data flow,
and run-time behavior. SV has been applied in various areas
like algorithm animation [20,34], software engineering, con-
current program execution [23], static and dynamic visual-
izations of object-oriented code [81,89], fault diagnostics [1,
95], debugging [4], and requirements analysis [24], to name
a few. An extensive compilation of research relating to these
fields can be found in [28,58,108].
A number of taxonomies have been developed that iden-
tify the properties of SV systems [79,85,86,94]. Attributes
defined by Roman and Price [86,94] include:
Scope and content: What is the aspect of the program being
visualized?
Abstraction: What kind of information is conveyed by the
visualization?
Form and technique: How is the graphical information be-
ing conveyed?
Method: How is the visualization specified?
Interaction: How can the user interact with the visualiza-
tion?
Staskoand Patterson [106] identify an additional property, the
level of automation provided for developing the SV system.
A task-oriented view of SV [72,75] uses the argument that
no single SV tool or technique can address all visualization
tasks. It is, therefore, necessary to identify the most appro-
priate visualization technique for the given SV task based on
the SV dimensions [72]:
Tasks: Why is the visualization needed?
Audience: Who will use the visualization?
222 D. Graˇcanin et al.
Target: What is the data source to represent?
Representation: How should it be represented?
Medium: Where should the visualization be represented?
2 Evolution of software visualization
SV has progressed from using simple two-dimensional (2D)
graphs [8,80,105,107,124] to three-dimensional (3D) rep-
resentations [75,76,91] and, more recently, virtual environ-
ments (VEs).
2.1 2D and 3D visualization
Two-dimensional SV techniques typically involve graph or
treelike representations consisting of a large number of nodes
and arcs [118]. A complex software system might include
thousands of such nodes and arcs. To make conceptualiza-
tion and comprehension easy for the user, visualizations of
such systems present pieces of the graph in different views
or different windows so that the user can focus on the level
of detail he desires. The software system is therefore rep-
resented in multiple windows that present to the observer
different characteristics of the system under consideration.
Examples of such visualization systems include Seesoft [38],
SHriMP [112], GROOVE [59], and FIELD [108].
Two-dimensional visualizations may lead to cluttering a
plethora of information on aflatplane.Eventhough pan/zoom
and fisheye views have been explored [112], visualizing soft-
ware in 2D does introduce a cognitive overload by presenting
too much information. Stasko [104] identifies the need for an
extra spatial dimension in visualizations and states that by
adding an extra spatial dimension, we supply visualization
designers with one more possibility for describing some as-
pect of a program or system.” An example of the advantages
of using 3D visualizations is the Cone Tree concept devel-
oped at Xerox PARC [104,121]. It has been claimed that the
cone tree can display up to 1000 nodes without visual clutter,
which is far beyond the capabilities of a 2D visualization.
The developed 3D visualization presents structured informa-
tion such as computer directories and project plans. In line
with representing the execution time behavior of object-ori-
ented code [59] in two dimensions, Stasko [104] discusses
the development of a system called POLKA-3D to represent
the same visualizations as a 3D animation.
Ware et al. [121] developed a system called GraphVisu-
alzer3D to visualize object-oriented code in 3D. They sug-
gest that perception is less error prone if software objects are
mapped to visual objects, as there is a natural mapping from
the former to the latter. They present the results of experi-
ments that analyzed perception in 2D and 3D and conclude
that there is encouraging empirical evidence that error rates in
perception are less in 3D visualization. One major advantage
of 3D visualization is that it allowsa user to perceivethe depth
of a presented structure. With 3D visualization, users can
zoom in or walk around structures or choose another angle
(by rotating the design) and hidden structures in a software
system may become evident. Three-dimensional visualiza-
tion might help identify new metaphors, fostering new ideas
with respect to design principles [41]. The hierarchy of rela-
tions and dependencies in design or source code would also
become more readily apparent because of the added depth. It
can also help to faster develop a “mental model” in the mind
of the user.
Another example of visualizing large nested graphs is
the NV3D system [84], which has been tested with graphs
containing more than 35,000 nodes and 100,000 relation-
ships. The NV3D system uses techniques like rapid zoom-
ing, elision, and 3D interactive visualization to display nested
graphs. Both the NV3D system and the POLKA-3D system
[104] analyze issues like spatial navigation, layout, semiot-
ics, and common uses of the third dimension to represent
characteristics like value, structure position, history of com-
putation, state of computation, and aesthetics to refine the
appearance of a 3D visualization.
Three-dimensional visualization has been explored for all
areas where 2D visualization is used, including metrics-based
visualization of object-oriented programs and visualization
to track software errors, isolate problems, and monitor pro-
gress of development [18,19,67]. Three-dimensional UML
(Unified Modeling Language) representations have also been
researched [37].
2.2 Virtual environments
Virtual environments (VEs) open possibilities of “immer-
sion” and “navigation” that may help to better explore soft-
ware structure. VEs enable the user to interact with a repre-
sentation of something familiar, namely a world with familiar
objects that he/she can interact with. The concept of “worlds”
in a VE can be mapped to “entities” or “components” in
object-oriented code or a software system. It is possible for
all software artifacts from requirements to source code to
be represented and linked in a VE to improve comprehen-
sion. VEs would enable users to navigate through these links
faster and in a more intuitive manner than 2D representations
or even 3D structures.
Softwaresystems are largecomplexsystems composed of
multiple components. To effectively comprehend these sys-
tems, it is necessary to provide varying levels of detail. Any
user attempting to understand the system must be able to
zoom out and in to each level of detail as necessary. 3D
visualizations and VEs allow a user to concentrate on one
aspect of the world in detail while providing a distant view
of other aspects that are situated farther away. As the user
moves close to each entity or visual component, it comes
to “life” or presents a higher level of detail. This technique,
called elision, is a major property ofVEs that abstracts distant
objects and details closer objects. The user can move back
and forth between objects or structures in this world and ro-
tate them around to view information that might be hidden
from normal view.
Software visualization 223
Examples of SV systems that use VEs for representing
object-oriented software systems are ImsoVision [71] and
Software World [60]. The former represents C++ code in an
immersive VE, while the latter does the same for static Java
code. A major characteristic of both systems is the mapping
of static properties of object-oriented code to objects in the
VE. ImsoVision uses geometrical 3D shapes like platforms,
spheres, and horizontal and vertical columns as visual met-
aphors for the characteristics of C++ code, while Software
World uses real-world metaphors like the world, countries,
districts, and buildings as visual metaphors for the various
parts of Java code. An example of elision can be seen in the
ImsoVision system [71], which hides the private attributes of
an object under the platform that represents the object. The
private attributes are visible only when the user rotates the
platform around.
Both visualization systems visualize only static proper-
ties of code. They cannot be used to characterize the run-time
behavior of an object-oriented system. While it is evident that
VEs provide a far richer experience than 2D visualizations
for a user attempting to comprehend a software system, it
is necessary to further investigate metaphors and represen-
tations that allow us to move beyond visualizing static code
[2].
2.3 Distributed VEs
A distributed (networked) VE (DVE or net-VE) is a software
system in which multiple users interact with each other in
real time, even though those users may be physically located
around the world [99]. The users have a shared sense of space,
a shared sense of presence, a shared sense of time, a way to
communicate, and a way to share [99]. DVEs can be used for
collaborative SV-based applications dealing with large and
distributed software projects including coding, maintenance,
and interactive visualization [2].
WYSIWIS (WhatYou See Is What I See) is the basic ab-
straction that guides such multiuser interfaces, and the design
provides a sense of teamwork. WYSIWIS is crucial for col-
laboration; however, some research has indicated that strict
objectivity is too inflexible. It may actually hinder collabo-
ration in some cases since the users are forced to agree on a
common representation and can only see the same things in-
stead of being able to tailor their representation of the virtual
scene to meet their needs [103,109,110].
Indeed, collaboration in the real world often proceeds
without the participants having access to the same
information. This has led to the development of the Relaxed-
WYSIWIS concept. Snowdon introduced the term “subjec-
tive views” for the concept of multiple perspectives in VEs
[103]. A subjective VE can give the user the ability to control
the presentation style to best suit her working needs.
SOLVEN is a model to support subjective views [100].
The core feature of SOLVEN is an access matrix, which de-
fines the representation of individual objects for individual
users. The matrix defines an object’s view in terms of two
Software
Graphical
Representation
Visualization
Fig. 1 Mapping software to a graphical representation
independent factors, appearance (differing geometric defi-
nition) and modifier (highlighting and deemphasizing abili-
ties).
VR-VIBE is a multiuser 3D visualization of a collection
of documents or document references [102]. The visualiza-
tion is structured using a 3D spatial framework of keywords,
called points of interest, or POIs.
Grimstead et al. [48] describe the use of a distributed,
collaborative grid-enabled visualization environment. The
resource-aware visualization environment (RAVE) was de-
ployed as Web Services and accessed using a simple PDA.
Efforts like these clear the path for large-scale, multiuser.
3 Metaphors in SV
Building on ideas stated in the previous section, a metaphor
can be defined as a rhetorical figure whose essence is un-
derstanding and experiencing one kind of thing in terms of
another [63]. Metaphors in the medium of representation af-
fect the expressiveness of the visualization. Metaphors might
be abstract geometrical shapes (as in ImsoVision, NV3D,
GraphVisualizer3D) or they might be real-world entities (as
in Software World). While it is true that a user would be more
familiar with a real-world metaphor, the visual complexity of
the metaphor should not affect the effectiveness of the visual-
ization. Roman and Cox [93] represent the role of the visual
metaphor in a program visualization as shown in Fig. 1 [2].
Evidently, a metaphor is the entity that gives shape to the
different faces of intangible software [2]. The next questions
in investigating VE visualization techniques are: What are
the characteristics of an effective metaphor for a VE? What
are the desirable characteristics of a VE for visualizing an
object-oriented system? It is necessary to state the desirable
properties of a metaphor for SV in 2D, 3D, or VEs. While
considering the properties of a metaphor, issues that arise
regarding the characteristics of the SV system can also be
discussed.
Mackinlay discusses graphical design issues on the ba-
sis of two criteria: expressiveness and effectiveness [70].
Expressiveness refers to the medium used to express the
graphical representation, and effectiveness is the extent to
which the representation is effective for comprehension of
the visualized information. These two criteria form the basis
on which we propose our design issues for effective visual-
izations. To be effective and meaningful, any visualization
system should consider the following key areas.
(1) Scope of the representation: Visualizing complex, real-
time systems can create chaos if the scope of the SV is
224 D. Graˇcanin et al.
not defined. Scope, as identified by Price et al. [86], is
isolating the characteristics of the system that the visu-
alization will address. The SV might choose to address
static or dynamic features of the software, or it might
choose to represent control flow, data flow, dependen-
cies, or all three. For example, visualization of Java
source code might address the classes in other pack-
ages that a particular class depends on or inheritance
hierarchies for a class or interface dependencies for a
class, to name a few possibilities.
(2) Medium of representation: The type of information be-
ing visualized and the level of detail required in the
visualization are just two factors that dictate the type
of output medium needed. If the system to be visual-
ized is relatively small and if detail like complexity of
the source code, version history, detailed dependency
navigation, or linking of the graphical representation to
source code is not needed, a simple 2D graph is suffi-
cient. If, however, the system to be visualized should
provide detailed information like security vulnerabili-
ties in the code and design or if the representation should
present varying levels of information about the system
without overwhelming the user, then 3D visualizations
might be considered.
(3) Visual metaphor: Metaphors in the medium of repre-
sentation affect the expressiveness of the visualization.
Metaphors might be abstract geometrical shapes (as in
ImsoVision, NV3D, GraphVisualizer3D, and other 2D
representations) or they might be real-world entities (as
in Software World). The visual complexity of the met-
aphor should not affect the effectiveness of the visuali-
zation. However, in the case of DVEs [10], users might
feel more comfortable interacting with their colleagues
in a real-world immersive VE.
(a) Consistency of the metaphor: The metaphor or the
mapping from software artifacts to the representa-
tions should be consistent throughout the visualiza-
tion. Multiple software artifacts cannot be mapped
to the same metaphor. Similarly, a software artifact
cannot be mapped to multiple metaphors. In a VE,
the metaphor should be consistent with the world it
is present in.
(b) Semantic richness of the metaphor and complexity:
The metaphor chosen should be rich enough to pro-
vide mappings for all aspects of the software that
need to be visualized. The scope of the representa-
tion determines to a certain extent the nature of the
metaphor to be chosen. There should be enough ob-
jects or equivalent representations in the metaphor
for the software entities that need to be visualized.
The SV should not divert the user from the informa-
tion that the SV system is attempting to convey. The
VE should provide pertinent representations with-
out giving the user the impression of immersion in
endless space. Similar views can be found in [123].
(4) Abstractedness: The user of the visualization system
should be able to focus away from certain parts of the
representation and focus in detail on other parts of the
representation. This is the property of elision (used in
NV3D [84]) that permits different users to focus on the
level of detail they desire. For example, if a visuali-
zation system should aid an evaluator in discovering
security vulnerabilities, the evaluator would look for
different levels of detail (say, low-level representations
that map to source code) as opposed to a user who will
be interested only in visualizing if any security prob-
lems exist in the system. This ability to zoom in and
zoom out is what makes navigation through a 3D system
easier than understanding a 2D representation. Roman
and Cox [93] identify different levels of abstractedness,
namely direct representation, structural representation,
synthesized representation, and analytical representa-
tion.
(5) Ease of navigation and interaction: Ease of navigation
is obviously a major design issue when constructing a
visualization. The user should understand what is pre-
sented and what level of abstraction in the system he is
currently at. It should be easy for the user to move back
and forth between different views or different worlds (in
the case of VEs). Also, the nature of the medium of rep-
resentation would affect the level of navigation a user
expects to have in the visualization. Three-dimensional
visualizations should allow users to rotate the entities
around for different angles of view. It should be pos-
sible to hide or “close” objects that are not of interest
by clicking on them or interacting with them in other
ways.
(6) Level of automation: Automation specifies the degree
to which the construction of the SV system is auto-
matic. Effective visualizations would need to be fully
automated for SV to be more widely used.
4 Software visualization tools and applications
Based on concepts and developments in information visuali-
zation [14,111,117], usability [77], and software engineering
[16,42,68], new SV frameworks, notations [22], query lan-
guages [87], and techniques are proposed [26,29,32]. New
SV models enable interactive, online configuration of SV
views and mappings (Vizz3D [83]) and better support for
software comprehension [12,82,116].
The rube framework presents models (multimodels) and
their visualizations that are based on user-specified meta-
phors and aesthetics [53]. The RiOT framework can be used
to manage testing and provide dynamic visualization of heter-
ogeneously distributed component-based applications [46].
The Source Viewer 3D (sv3D) uses a 3D metaphor to repre-
sent software system and analysis data that extends the See-
soft pixel metaphor by rendering the visualization in a 3D
space [73].
Many SV tools have been developed for specific aspects
of software design and development[113,115]. CodeCrawler
is an example of a lightweight SV tool that combines met-
Software visualization 225
rics information with its visualizations [64,65]. SV tools can
be integrated within an integrated development environment
(IDE) such as Eclipse [69]. SV tools can also be accessed on
the Web [31] and presented as Web services [33].
Object-oriented aspects are often a topic of SV research
[51] that includes evolution of class hierarchies [47], ver-
sioning [11,96], run-time visualization [101], metrics [57],
and component-based software [40]. It also includes C++
[62] and Java [17,45,88] programming languages, as well as
UML [54,74].
Other SV areas include formalisms [3], metrics [9,66,
98], slicing [27,92,90], and XML [52,78,114], to name a
few. The remainder of this section discusses SV for software
evolution, software security, data mining in software systems,
algorithms, and software engineering education.
4.1 Software evolution
Software is continually changing and evolving [39]. Today’s
typical software system is a complex beast spanning millions
of lines of code. Manually analyzing the effects and impacts
of changes [56] to a software system is a labor-intensive and
often error-prone task. Visualizing the evolution of the sys-
tem may be accomplished, in part, through visualizing the
version history of a software system. Visualizing version his-
tory typically involves visualizing metrics such as number
of lines of code in a particular version of a file included in
the system, the percentage of growth and the percentage of
change in the system, defect density, and change complex-
ity measures [44]. This section discusses advances in version
history visualization.
An important construct in most of the works discussed
below is that of a modification request or maintenance request
(MR). A software system is assumed to consist of subsys-
tems. Each of these subsystems has a number of modules.
The modules include the program elements, which may be
a collection of one or more source files, and an MR is the
information representing work to be done to each module.
Deltas are part of an MR, representing editing changes made
to individual files in order to complete an MR. A file can
be checked out, edited, and then checked in [6,43]. Note that
this terminology works well with version control systems that
can record the parent MR for each delta list, along with the
number of lines added, deleted, and modified by that change.
Alternatively, as in the case of CVS, there is no concept of an
MR. Changes made to files are recorded as part of a checkout
or update of modules.
The forerunner to most of the attempts at version history
visualization can be seen in Seesoft, developed by Eick et
al. [38]. Seesoft is a tool for visualization of line-oriented
software statistics. Seesoft can visualize up to 50,000 lines
of code and provides information about various statistics like
the number of files under version control, the age of each line
of code in a file, the number of lines of code in each file, the
MR that touched a particular line of code in a file, and the
number of times the line was executed during testing. Seesoft
uses a row–column metaphor. Each column represents a file
and the rows in each column represent the number of lines of
code in the file. It allows user interaction to decipher inter-
esting patterns in the version history and also provides infor-
mation about the dates of changes, the reasons for changes,
the developer who changed the code, etc.
Another significant effort in version history visualization
is presented by Gall et al. [44]. Their work uses color and
the third dimension effectively to visualize software release
histories. The metrics that they visualize include size of the
system in terms of lines of code, age in terms of version num-
bers, and error-proneness in terms of defect density. Their
Software Release History visualization is composed of three
entities:
Time: The visualization is grouped according to the re-
lease sequence number (RSN). A snapshot of the system
at the time of each release enables the end user to see
the evolution of files between releases. Addition, dele-
tion, and modification of files between releases are clearly
visible.
Structure: The system is decomposed into subsystems.
Each subsystem is decomposed into modules, and each
module comprises the source code files.
Attributes: These include version number, size, change
complexity, and defect density.
The visualization wascreated using Java and virtual reality
modeling language (VRML) to render and navigate the 3D
spaces. The end user can navigate through the visualization
and use the mouse to extract information about the structure
of the entire system for a release or focus on a particular sub-
system and extractthe valuesof the modules in the subsystem.
The paper concludes with the suggestion that other metrics
like lines of code, complexity measures, and defect density
can be visualized. It also suggests the automatic detection of
change patterns to identify module dependencies. The type
of change pattern to be investigated could be input by the
user.
Gall et al. [43] discuss another application of version
history visualization. They present an approach that uses
information in the release history of a system to uncover log-
ical dependencies and change patterns among modules. They
have developed a technique that automatically extracts infor-
mation about the logical dependencies among the modules of
a system. These logical dependencies are different from the
syntactic dependencies that are evident through source code
analysis. The authors propose the idea of change sequence
analysis and change report analysis to identify logical depen-
dencies. The change sequence analysis lists the releases in
which a module was changed. Different modules can be com-
pared on the basis of such change sequences, and common
change patterns can be identified.
Lanza and Ducasse in [35,36] study the evolution of clas-
ses in a system using a combination of SV and software
metrics. The visualization is 2D, with rows representing the
classes in a system and columns denoting the version of the
system. The first column would represent version 1 of the sys-
tem, the second version 2, and so on. The number of methods
226 D. Graˇcanin et al.
in the class decides the width of each rectangle representing
a class, while the number of instance variables in the class
decides the height of the rectangle. The authors suggest that
other metrics can also be used effectively to represent a class.
This metaphor allows easy visualization of the number of
classes in the system, the most recent classes that have been
added to the system, and growth and stagnation phases in the
evolution of the system. An innovative technique here is the
classification of classes based on the kind of changes made
to them over the different versions of the system.
Koike [61] presents a 3D visualization framework
(VRCS) by means of which a user can interact with a version
control system. Versions of the files in a system are repre-
sented as cubes arranged along the z-axis, ordered by time.
Releases that link versions of various files together are rep-
resented as circles. VRCS has been implemented using Op-
enGL/C and serves as an interface to RCS. Users can check
out, edit, and check in files, view differences between two
cubes/versions of a file, retrieve all the files that comprise a
release, and even build the executable file for a release. The
authors also suggest some mechanism that enables the user to
select the amount of graphical information presented. VRCS
can only be applied to single-user systems.
Finally, CVSscan [120] is an integrated multiview envi-
ronment that helps users to better understand the status, his-
tory, and structure of the source code, as well as, for instance,
the roles played by various contributors.
4.2 Software security
One possible application of SV is in the area of software
security analysis. For example, visualizing the results of de-
pendency analysis and traceability analysis in a software sys-
tem can help identify the potential security vulnerabilities if
proposed changes to a system are implemented.
Conti and Abdulla [21] discuss the use of SV for security
analysis. The authors examine the visual fingerprints left by
a wide variety of popular network attack software tools to
provide better understanding of the specific methodologies
used by attackers as well as the identifiable characteristics
of the tools themselves. The techniques used in the paper
are entirely passive in nature, making them virtually unde-
tectable by attackers. The paper explores the application of
several visualization techniques including parallel coordinate
plots and scrolling plots for their usefulness in identifying
attack tools, without the typical automated intrusion detection
system’s signatures and statistical anomalies. These visual-
izations were tested using a wide range of popular network
security tools, and the results showed that in many cases, the
specific tool can be identified.
While Conti and Abdullah [21] focused on attack tool
fingerprints, Yoo in [122] studied virus fingerprints. Their
paper focused on visualizing Windows executable viruses
using self-organizing maps (SOMs) without using virus-spe-
cific signature information as a prior stage of detecting com-
puter viruses. SOMs are visualized using the unified distance
matrix. The paper addresses the fact that each virus has its
own character to be distinguished, although it is inserted in
the executable file. Yoo observed that the virus features can-
not be hidden through the SOM visualization; these features
are like a strand of DNA that determines a person’s unique
genetic code. The authors studied how virus codes effect the
whole program projection, without each virus signature, and
described how a virus pattern in Windows executable files
indicates its family. The paper also shows that variants of
a virus can also be covered with the specific virus’s mask,
which is produced by SOM.
4.3 Data mining in software systems
Visualization is employed in data mining to visually pres-
ent already discovered patterns and to discover new patterns
visually. Success in both tasks depends on the system’s ability
to present abstract patterns as simple visual patterns [119].
SV is used in Burch et al. [15] for mining software
archives. A software archive is comprised of the informa-
tion stored by a configuration management system and re-
lated tools. This information includes versions, changes, bug
databases, and electronic mail. The authors claim that the
relevance to a project or set of projects of many software
engineering rules published in the literature is unclear; either
the rules are too general or results of the case studies cannot
be transferred, because the constraints of the case studies are
not well documented. The authors use visual data mining for
extracting rules from software archives for validation of the
application of these rules and also for discovering new pro-
ject-specific rules. The authors developed EPOSee to visual-
ize n-ary association and sequence rules and to study software
evolution and relations based on hierarchically ordered items.
EPOSee uses pixelmaps and parallel coordinate views and
provides visualizations that conform to Ben Shneiderman’s
visualization mantra: “Overview first, zoom and filter, then
details on demand” [97]. As an example, the paper studies
the large software archive of the Mozilla open source project.
Vityaev and Kovalerchuk[119] propose a technique called
inverse visualization (IV) to address the problem of visual-
izing complex patterns. Their approach does not use data
“as is” and does not follow a traditional sequence: discover
pattern—visualize pattern. Instead, the sequence proposed
[119] is: convert data to visualizable form—discover pat-
terns with predefined visualization. IV is based on specially
designed data preprocessing that permits the discovery of ab-
stract patterns that can be presented by simple visual patterns.
In the paper, the feasibility of solving inverse visualization
tasks is illustrated on functional nonlinear additive depen-
dencies that are transformed into simple and intuitive visual
patterns.
4.4 Algorithms and software engineering education
Algorithm and software engineering visualization can help
instructors to explain and learners to understand algorithms
and software engineering principles and practices [55]. For
example, an algorithm can be animated showing relevant
Software visualization 227
parameters and variables, the current state, and a visual repre-
sentation of the objects being manipulated, as well as an ani-
mated formal description of the algorithm. Complex model
structures are simplified at a high level of abstraction to high-
light only the important aspects. Details can then be shown
at lower levels of abstraction by omitting irrelevant details.
For better comprehension, the designer scales down data to
coarser structures and slows down algorithms that process
data. Smooth transitions between different states of moving
objects can make it easier to follow the way the algorithm
works on graphical representations of data structures.
A recent proposal by Baloian et al. [7] concerns an
approach to developing algorithm visualization that seeks to
construct context-dependent interfaces allowing the learner
to interactively control and explore the actions in the algo-
rithm.The proposed approach replaces standard control using
mouse clicks on graphic displays with a concept called con-
cept keyboards (CKs) mirroring the inherent logical struc-
tures of the algorithm under investigation. The CK concept
separates control elements, data input, and visual output ob-
jects by means of an adequate concept keyboard application
to be used to configure keyboards, collect startup data, and
visualize user actions.
A key on a CK has a special meaning (concept) associ-
ated with it instead of just a label. Each key of the CK will be
mapped to the execution of an existing method available in
the algorithm implementation. In order to choose the interest-
ing events (those that are crucial for understanding the algo-
rithm), the designer has a simple GUI displaying the available
actions and allowing them to select the relevant ones. CKs are
used to trigger more complex semantic actions on the system
in which they have been implemented. The special software
supplied allows the user to redefine the function of each key
and to regroup keys into fields of differing sizes. The user’s
attempts at manipulation of algorithms and data structures
are reflected by changes in the visualization or another form
of output like textual or acoustic information. This provides
users, including people with sensory disabilities, with suit-
able interfaces that may enhance the comprehension of the
algorithm being presented.
The GRASP, and its successor jGRASP, were developed
in [25,50] with the goal of enhancing software system com-
prehension efficiency and effectiveness. The developed visu-
alization tools support well-defined cognitive processes
employed during a comprehension task, such as top-down,
bottom-up, and mixed comprehension models. Grissom et al.
[49] measured the effect of varying levels of student engage-
ment with algorithm visualization to learn simple sorting
algorithms. Their results showed that learning increases as
the level of student engagement increases. The authors con-
cluded that algorithm visualization has a bigger impact on
learning when students go beyond merely viewing a visu-
alization and are required to engage in additional activities
structured around the visualization.
5 Conclusions
Advances in SV are leading to its pervasive adoption for bet-
ter comprehension, engineering, and consequently, enhance-
ments in algorithm animation, software evolution, and
software metrics. Development of secure software and soft-
ware engineering education products is also a major benefit.
Interactivevisualization can be coupled with other modal-
ities, such as sensing or predictive methods, to provide pow-
erful new capabilities for SV as well as other visualization
domains. In addition, the fusion of visualization techniques
with other areas such as data mining, grid computing, and
Web Services is promoting broad-based advances, particu-
larly in the emerging areas of visual analytics and mobile
visualization. Another promising area of SV advancement is
collaborative VEs that will lead to better understanding of
collaborative software engineering processes.
Indeed, the importance of SV is growing, both in acade-
mia and industry [13]. A recent survey of software mainte-
nance, reengineering, and reverse engineering studies
[29,30] shows that 40% of researchers consider SV “abso-
lutely necessary for their work” while 42% of researchers
consider it “important but not critical.” In addition, a sig-
nificant increase in SV research is apparent in the plethora
of recent conferences, workshops, and symposia on SV. For
a wide spectrum of new ideas and approaches, the reader
is referred to the Dagstuhl seminar “Software Visualization”
(2001), the ACM Symposium on Software Visualization
(2003, 2005), and the IEEE International Workshop on Visu-
alizing Softwarefor Understanding andAnalysis (2002, 2003,
2005).
References
1. Amari H, Okada M (1999) A three-dimensional visualization tool
for software fault analysis of a distributed system. In: Proceedings
of the IEEE systems, man, and cybernetics conference (SMC’99),
4:194–1999
2. Asokan R (2003)Automatic visualization of the version history of
a software system in three dimensions. Master’s thesis, Virginia
Polytechnic Institute and State University, Falls Church, VA
3. Averbukh VL (1997) Toward formal definition of conception
“adequacy in visualization”. In: Proceedings of the 1997 IEEE
symposium on visual languages, pp 46–47
4. Baecker R, DiGiano C, Marcus A (1997) Software visualization
for debugging. Commun ACM 40(4):44–54
5. Ball T, Eick SG (1996) Software visualization in the large. IEEE
Comput 29(4):33–43
6. Ball T, Kim JM, Porter AA, Siy HP (1997) If your version control
system could talk ... . In: Proceedings of the ICSE workshop on
process modelling and empirical studies of software engineering
7. Baloian N, Breuer H, Luther W (2005) Algorithm visualization
using concept keyboards. In: Proceedings of the 2005 ACM sym-
posium on software visualization (SoftVis’05). ACM Press, New
York, pp 7–16
8. Balzer M, Deussen O (2004) Hierarchy based 3D visualization
of large software structures. In: Proceedings of the conference on
visualization (VIS’04). IEEE Press, Washington, DC, p 598.4
228 D. Graˇcanin et al.
9. Balzer M, Deussen O, Lewerentz C (2005) Voronoi treemaps for
the visualization of software metrics. In: Proceedings of the 2005
ACM symposium on software visualization (SoftVis’05). ACM
Press, NewYork, pp 164–172,214
10. Bassil S, Keller RK (2001) Software visualization tools: survey
and analysis. In: Proceedings of the 9th international workshop
on program comprehension (IWPC 2001), Toronto, pp 7–17
11. Bieman JM,AndrewsAA,Yang HJ (2003) Understanding change-
proneness in OO software through visualization. In: Proceedings
of the 11th IEEE international workshop on program comprehen-
sion (IWPC’03), pp 44–53
12. Boisvert C (2004) Supporting program development comprehen-
sion by visualising iterative design. In: Proceedings of the 8th
international conference on information visualisation (IV’04),
pp 717–722
13. Bril RJ, Postma A, Krikhaar RL (2003) Embedding architectural
support in industry. In: Proceedings of the international confer-
ence on software maintenance (ICSM’03), pp 348–357
14. Brown M, Domingue J, Price B, Stasko J (1994) Software visu-
alization: a CHI ’94 workshop. SIGCHI Bull 26(4):32–35
15. Burch M, Diehl S, Weissgerber P (2005) Visual data mining in
software archives. In: Proceedings of the 2005 ACM symposium
on software visualization (SoftVis’05). ACM Press, New York,
pp 37–46
16. Burnett M, Cook C, Rothermel G (2004) End-user software eng-
ineering. Commun ACM 47(9):53–58
17. Cattaneo G, Faruolo P, Petrillo UF, Italiano GF (2004) JIVE: Java
interactive software visualization environment. In: Proceedings
of the 2004 IEEE symposium on visual languages and human
centric computing (VLHCC’04), pp 41–43
18. Chuah MC, Eick SG (1997) Glyphs for software visualization. In:
Proceedings of the 5th iternational workshop on program com-
prehension (IWPC’97), pp 183–191
19. Chuah MC, Eick SG (1998) Information rich glyphs for software
management data. IEEE Comput Graph Appl 18(4):24–29
20. Collins TD (2003) Applying software visualization technology to
support the use of evolutionary algorithms. J Vis Lang Comput
14(2):123–150
21. Conti G, Abdullah K (2004) Passive visual fingerprinting of net-
work attack tools. In: Proceedings of the 2004 ACM workshop
on visualization and data mining for computer security (Viz-
SEC/DMSEC’04), pp 45–54
22. Costagliola G, Deufemia V, Polese G (2004) A framework
for modeling and implementing visual notations with applica-
tions to software engineering. ACM Trans Softw Eng Methodol
13(4):431–487
23. Cox P, Gauvin S, Rau-Chaplin A (2005) Adding parallelism to
visual data flow programs. In: Proceedings of the 2005 ACM
symposium on software visualization (SoftVis’05). ACM Press,
NewYork, pp 135–144
24. Cross II JH, Hendrix TD, Barowski LA, Mathias KS (1998) Scal-
able visualizations to support reverse engineering: a framework
for evaluation. In: Proceedings of the 5th working conference on
reverse engineering, pp 201–209
25. Cross II JH, Hendrix TD, Mathias KS, Barowski LA (1999)
Software visualization and measurement in software engineer-
ing education: an experience report. In: Proceedings of the 29th
ASEE/IEEE conference on frontiers in education, pp 12b1/5–
12b1/10
26. De Pauw W, Reiss SP, Stasko JT (2001) ICSE workshop on soft-
ware visualization. In: Proceedings of the 23rd international con-
ference on software engineering (ICSE’01), pp 758–759
27. Deng Y, Kothari S, Namara Y (2001) Program slice browser. In:
Proceedings of the 9th international workshop on program com-
prehension (IWPC’01), pp 50–59
28. Diehl S (ed) (2002) Proceedings of the international seminar
on software visualization, Dagstuhl Castle, Germany, 20–25
May 2001. Revised papers. Lecture notes in computer science,
vol 2269. Springer, Berlin Heidelberg New York
29. Diehl S (2005) Software visualization. In: Proceedings of the 27th
international conference on Software engineering (ICSE’05).
ACM Press, NewYork, pp 718–719
30. Diehl S, Kerren A (2002) Reification of program points for
visual execution. In: Proceedings of the 1st international work-
shop on visualizing software for understanding and analysis
(VISSOFT’02), pp 100–109
31. Domingue J, Mulholland P (1997) Staging software visualiza-
tions on the web. In: Proceedings of the 1997 IEEE symposium
on visual languages, pp 364–371
32. Domingue J, Sutinen E (2002) Software visualization – editorial.
J Vis Lang Comput 13(3):257–258
33. Dong J, Yang S, Zhang K (2005) VisDP: A web service for
visualizing design patterns on demand. In: Proceedings of the
international conference on information technology: coding and
computing (ITCC’05), 2:385–391
34. Douglas S, Hundhausen C, McKeown D (1995) Toward empir-
ically-based software visualization languages. In: Proceedings
of the 11th IEEE international symposium on visual languages,
pp 342–349
35. Ducasse S, Lanza M (2005) The class blueprint: visually support-
ing the understanding of classes. IEEE Trans Softw Eng 31(1):75–
90
36. Ducasse S, Lanza M, Bertuli R (2004) High-level polymetric
views of condensed run-time information. In: Proceedings of the
8th European conference on software maintenance and reengi-
neering (CSMR’04), pp 309–318
37. Dwyer T (2001) Three dimensional UML using force directed lay-
out. In: Proceedings of theAustralian symposium on information
visualisation 2001, Sydney, Australia, pp 77–85
38. Eick SG, Steffen JL, Summer EE Jr (1992) Seesoft: a tool for
visualizing line oriented software statistics. IEEE Trans Softw
Eng 18(11):957–968
39. Eick SG, Graves TL, KarrAF, Mockus A, Schuster P (2002)Visu-
alizing software changes. IEEE Trans Softw Eng 28(4):396–412
40. Favre JM, Cervantes H (2002) Visualization of component-
based software. In: Proceedings of the 1st international work-
shop on visualizing software for understanding and analysis
(VISSOFT’02), pp 51–60
41. Feijs L, Jong RD (1998) 3D visualization of software architec-
tures. Commun ACM 41(12):73–78
42. Fiutem R, Merlo E, Antonio G, Tonella P (1996) Understanding
the architecture of software systems. In: Proceedings of the 4th
workshop on program comprehension (WPC’06), pp 187–196
43. Gall H, Hajek K, Jazayeri M (1998) Detection of logical coupling
based on product release history. In: Proceedings of the inter-
national conference on software maintenance (ICSM’98). IEEE
Press, Washington, DC, p 190
44. Gall H, Jazayeri M, Riva C (1999) Visualizing software release
histories: The use of color and third dimension. In: Proceedings
of the IEEE international conference on software maintenance
(ICSM’99)
45. Gestwicki P, Jayaraman B (2005) Methodology and architecture
of JIVE. In: Proceedings of the 2005 ACM symposium on soft-
ware visualization (SoftVis’05). ACM Press, New York, pp 95–
104
46. Ghosh S, Bawa N, Craig G, Kalgaonkar K (2001) A test man-
agement and software visualization framework for heteroge-
neous distributed applications. In: Proceedings of the 6th IEEE
international symposium on high assurance systems engineering
(HASE’01), pp 106–116
47. Girba T, Lanza M, Ducasse S (2005) Characterizing the evolu-
tion of class hierarchies. In: Proceedings of the 9th European con-
ference on software maintenance and reengineering (CSMR’05),
pp 2–11
48. Grimstead IJ,Avis NJ, Walker DW (2005)Visualization across the
pond: How a wireless PDA can collaborate with million-poly-
gon datasets via 9,000 km of cable. In: Proceeding of the 10th
international conference on 3D web technology (Web3D 2005),
pp 47–56,187
49. Grissom S, McNally MF, Naps T (2003) Algorithm visualization
in CS education: comparing levels of student engagement. In: Pro-
ceedings of the 2003 ACM symposium on software visualization
(SoftVis’03), pp 87–94
Software visualization 229
50. Hendrix D, Cross II JH, Barowski LA (2004)An extensibleframe-
work for providing dynamic data structure visualizations in a
lightweight IDE. In: Proceedings of the 35th technical sympo-
sium on computer science education (SIGCSE’04), pp 387–391
51. Hill T, Noble J, Potter J (2002) Scalable visualizations of object-
oriented systems with ownership trees. J Vis Lang Comput
13(3):319–339
52. Hopfner M, Seipel D, von Gudenberg JW (2003) Comprehending
and visualizing software based on XML-representations and call
graphs. In: Proceedings of the 11th IEEE international workshop
on program comprehension (IWPC’03), pp 290–291
53. Hopkins JF, Fishwick PA (2003) The rube framework for software
modeling and customized 3-D visualization. J Vis Lang Comput
14:97–117
54. Huang S, Tilley S (2003) Workshop on graphical documentation
for programmers: assessing the efficacy of UML diagrams for
program understanding. In: Proceedings of the 11th IEEE inter-
national workshop on program comprehension, pp 281–282
55. Hundhausen CD, Douglas SA, Stasko JT (2002) A meta-study
of algorithm visualization effectiveness. J Vis Lang Comput
13(3):259–290
56. Hutchins M, Gallagher K (1998) Improving visual impact anal-
ysis. In: Proceedings of the international conference on software
maintenance, pp 294–303
57. Irwin W, Churcher N (2003) Object oriented metrics: precision
tools and configurable visualisations. In: Proceedings of the 9th
international software metrics symposium, pp 112–123
58. Jeffery CL (1999) Program monitoring and visualization: an ex-
ploratory approach. Springer, Berlin Heidelberg, New York
59. Jerding DF, Sasko JT, Ball T (1996) Visualizing message patterns
in object-oriented. Technical report GIT-GVU-96-15, Graphics,
Visualization, and Usability Center, College of Computing, Geor-
gia Institute of Technology, Atlanta
60. Knight C, Munro M (1999) Comprehension with[in] virtual env-
ironment visualisations. In: Proceedings of the 7th international
workshop on program comprehension, Pittsburgh, PA, pp 4–11
61. Koike H (1993) The role of another spatial dimension in software
visualization. ACM Trans Inf Syst 11(3):266–286
62. LaFollette P, Korsh J, Sangwan R (2000) A visual interface for
effortless animation of C/C++ programs. J Vis Lang Comput
11(1):27–48
63. Lakoff G, Johnson M (1980) Metaphors we live by. University of
Chicago Press, Chicago
64. Lanza M (2003) CodeCrawler: lessons learned in building a soft-
ware visualization tool. In: Proceedings of the 7th European con-
ference on software maintenance and reengineering (CSMR’03),
pp 409–418
65. Lanza M (2004) CodeCrawler: polymetric views in action. In:
Proceedings of the 19th international conference on automated
software engineering (ASE’04), pp 394–395
66. Lanza M, Ducasse S (2003) Polymetric views: a lightweight vi-
sual approach to reverse engineering. IEEE Trans Softw Eng
29(9):782–795
67. Lewerentz C, Simon F (2002) Metrics-based 3D visualization of
large object-oriented programs. In: Proceedings of the 1st inter-
national workshop on visualizing software for understanding and
analysis (VISSOFT’02), Paris, pp 70–77
68. Lieberman H, Fry C (2001) Will software ever work? Commun
ACM 44(3):122–124
69. Lintern R, Michaud J, Storey MA, Wu X (2003) Plugging-in
visualization: experiences integrating a visualization tool with
Eclipse. In: Proceedings of the 2003 ACM symposium on soft-
ware visualization (SoftVis ’03).ACM Press, NewYork, pp 47–56
70. Mackinlay JD (1986) Automating the design of graphical presen-
tations of relational information.ACMTrans Graph 5(2):110–141
71. Maletic JI, Leigh J, Marcus A, Dunlap G (2001) Visualiz-
ing object-oriented software in virtual reality. In: Proceedings
of the 9th international workshop on program comprehension
(IWPC’01), Toronto, pp 26–35
72. Maletic JI, Marcus A, Collard ML (2002) A task oriented view
of software visualization. In: Proceedings of the 1st international
workshop on visualizing software for understanding and analysis
(VISSOFT’02), pp 32–40
73. Maletic JI, Marcus A, Feng L (2003) Source viewer 3D (sv3D):
a framework for software visualization. In: Proceedings of the
25th international conference on software engineering (ICSE’03),
pp 812–813
74. Malloy BA, Power JF (2005) Exploiting UML dynamic object
modeling for the visualization of C++ programs. In: Proceedings
of the 2005 ACM symposium on software visualization (Soft-
Vis’05). ACM Press, New York, pp 105–114
75. Marcus A, Feng L, Maletic JI (2003a) 3D representations for soft-
ware visualization. In: Proceedings of the 2003 ACM symposium
on software visualization (SoftVis’03). ACM Press, New York,
pp 27–36
76. Marcus A, Feng L, Maletic JI (2003b) Comprehension of soft-
ware analysis data using 3D visualization. In: Proceedings of the
11th IEEE international workshop on program comprehension
(IWPC’03), pp 105–114
77. Marcus A, Comorski D, Sergeyev A (2005) Supporting the evo-
lution of a software visualization tool through usability studies.
In: Proceedings of the 13th international workshop on program
comprehension (IWPC’05), pp 307–316
78. Marks RM, Wilkie FG (2004) Visualising object-oriented source
code complexity using XML. In: Proceedings of the 9th IEEE
international conference on engineering complex computer sys-
tems navigating complexity in the e-Engineering age, pp 161–170
79. Myers BA (1990) Taxonomies of visual programming and pro-
gram visualization. J Vis Lang Comput 1(1):97–123
80. Noack A, Lewerentz C (2005) A space of layout styles for hierar-
chical graph models of software systems. In: Proceedings of the
2005 ACM symposium on software visualization (SoftVis ’05).
ACM Press, NewYork, pp 155–164
81. Pacione MJ (2004) Software visualisation for object-oriented pro-
gram comprehension. In: Proceedings of the 26th international
conference on software engineering (ICSE’04), pp 63–65
82. Pacione MJ, Roper M, Wood M (2004)A novelsoftwarevisualisa-
tion model to support software comprehension. In: Proceedings of
the 11th working conference on reverse engineering (WCRE’04),
pp 70–79
83. Panas T, Lincke R, Löwe W (2005) Online-configuration of soft-
ware visualizations with Vizz3D. In: Proceedings of the 2005
ACM symposium on software visualization (SoftVis’05). ACM
Press, NewYork, pp 173–182
84. Parker G, Franck G, Ware C (1998) Visualization of large nested
graphs in 3D: Navigation and interaction. J Vis Lang Comput
9(3):299–317
85. Price BA, Small IS, Baecker R (1992) A taxonomy of software
visualization. In: Proceedings of the 25th Hawaii international
conference on system sciences, 2:597–606
86. Price BA, Baecker RM, Small IS (1993) A principled taxonomy
of software visualization. J Vis Lang Comput 4(3):211–266
87. Reiss SP (2002) A visual query language for software visuali-
zation. In: Proceedings of the IEEE 2002 symposia on human
centric computing languages and environments (HCC’02), pp 80–
82
88. Reiss SP (2003) JIVE: Visualizing java in action. In: Proceed-
ings of the 25th international conference on software engineering
(ICSE’03), pp 820–821
89. Reiss SP (2005) Tool demonstration: JIVE and JOVE: Java as it
happens. In: Proceedings of the 25th international conference on
software engineering (ICSE’03), pp 820–821
90. Rilling J, Mudur S (2005) 3D visualization techniques to
support slicing-based program comprehension. Comput Graph
29(3):311–329
91. Rilling J, Mudur SP (2002) On the use of metaballs to visually
map source code structures and analysis results onto 3D space. In:
Proceedings of the 9th working conference on reverse engineering
(WCRE’02), pp 299–308
230 D. Graˇcanin et al.
92. Rilling J, Seffah A, Bouthlier C (2002) The CONCEPT project:
applying source code analysis to reduce information complexity
of static and dynamic visualization techniques. In: Proceedings of
the 1st international workshop on visualizing software for under-
standing and analysis (VISSOFT’02), pp 90–99
93. Roman GC, Cox KC (1992) Program visualization: the art of
mapping programs to pictures. In: Proceedings of the 14th inter-
national conference on Software engineering. ACM Press, Mel-
bourne, pp 412–420
94. Roman GC, Cox KC (1993)A taxonomy of program visualization
systems. IEEE Comput 26(12):11–24
95. Ruthruff J, Creswick E, Burnett M, Cook C, Prabhakararao S,
M Fisher I, Main M (2003) End-user software visualizations for
fault localization. In: Proceedings of the 2003 ACM symposium
on software visualization (SoftVis’03). ACM Press, New York,
pp 123–132
96. Seemann J, von Gudenberg JW (1998) Visualization of differ-
ences between versions of object-oriented software. In: Proceed-
ings of the 2nd Euromicro conference on software maintenance
and reengineering, pp 201–204
97. Shneiderman B (2002) Creativity support tools. Commun ACM
45(10):116–120
98. Simon F, Steinbrückner F, Lewerentz C (2001) Metrics based
refactoring. In: Proceedings of the 5th European conference on
software maintenance and reengineering, pp 30–38
99. Singhal S, Zyda M (1999) Networked virtual environments: de-
sign and implementation. ACM Press SIGGRAPH Series, Addi-
son-Wesley, Reading, MA
100. Smith G, Mariani J (1997) Using subjective views to enhance 3D
applications. In: Proceedings of the ACM symposium on virtual
reality software and technology. ACM Press, New York, pp 139–
146
101. Smith MP, Munro M (2002) Runtime visualisation of object
oriented software. In: Proceedings of the 1st international work-
shop on visualizing software for understanding and analysis (VIS-
SOFT’02), pp 81–89
102. Snowdon D, Jää-Aro KM (1997) A subjective virtual environ-
ment for collaborative information visualization. In: Virtual Real-
ity Universe’97, Santa Clara, CA
103. Snowdon D, Greenhalgh C, Benford S (1995) What you see is not
what I see: subjectivity in virtual environments. In: Framework
for immersive virtual environments (FIVE’95), QMW University
of London, UK
104. Stasko JT (1992) Three-dimensional computation visualization.
Technical report GIT-GVU-94-33, Graphics, Visualization, and
Usability Center, College of Computing, Georgia Institute of
Technology, Atlanta
105. Stasko JT, Muthukumarasamy J (1996) Visualizing program exe-
cutions on large data sets. In: Proceedings of the 1996 IEEE sym-
posium on visual languages, pp 166–173
106. Stasko JT, Patterson C (1992) Understanding and characterizing
software visualization systems. In: Proceedings of the 1992 IEEE
workshop on visual languages, Seattle, pp 3–10
107. Stasko JT, Turner CR (1992) Tidy animations of tree algorithms.
In: Proceedings of the 1992 IEEE workshop on visual languages,
Seattle, pp 216–218
108. Stasko JT, Domingue JB, Brown MH, Price BA (eds) (1998) Soft-
ware visualization. MIT Press, Cambridge, MA
109. Stefik M, Bobrow DG, Foster G, Lanning S, Tatar D (1987a)
WYSIWIS revised: early experiences with multiuser interfaces.
ACM Trans Inf Sys 5(2):147–167
110. Stefik M, Foster G, Bobrow DG, Kahn K, Lanning S, Suchman L
(1987b) Beyond the chalkboard: computer support for collabora-
tion and problem solving in meetings. Commun ACM 30(1):32–
47
111. Storey MAD, Fracchia FD, Müller HA (1997a) Cognitive design
elements to support the construction of a mental model during
software visualization. In: Proceedings of the 5th international
workshop on program comprehension (IWPC 1997), Dearborn,
MI, pp 17–28
112. Storey MAD, Wong K, Fracchia FD, Müller HA (1997b) On int-
egrating visualization techniques for effective software explora-
tion. In: Proceedings of the 1997 IEEE symposium on information
visualization, Phoenix, AZ, pp 38–45
113. Storey MAD,
ˇ
Cubrani´c D, German DM (2005) On the use of
visualization to support awareness of human activities in software
development: a survey and a framework. In: Proceedings of the
2005 ACM symposium on software visualization (SoftVis’05).
ACM Press, NewYork, pp 193–202
114. Telea A, Maccari A, Riva C (2002) An open visualization toolkit
for reverse architecting. In: Proceedings of the 10th international
workshop on program comprehension (IWPC’02), pp 3–10
115. Tilley S, Huang S (2002) On selecting software visualization tools
for program understanding in an industrial context. In: Proceed-
ings of the 10th international workshop on program comprehen-
sion (IWPC’02), pp 285–288
116. Tudoreanu ME (2003) Designing effective program visualization
tools for reducing user’s cognitive effort. In: Proceedings of the
2003 ACM symposium on software visualization (SoftVis’03).
ACM Press, NewYork, pp 105–114
117. Tufte E (1990) Envisioning information. Graphics Press, Chesh-
ire, UK
118. van Ham F (2003) Using multilevel call matrices in large soft-
ware projects. In: Proceedings of the 2003 IEEE symposium on
information visualization (INFOVIS’03), pp 227–232
119. Vityaev E, Kovalerchuk B (2002) Inverse visualization in data
mining. In: Proceedings of the 2002 international conference on
imaging science, systems, and technology, pp 133–137
120. Voinea L, Telea A, van Wijk JJ (2005) CVSscan: visualization
of code evolution. In: Proceedings of the 2005 ACM symposium
on software visualization (SoftVis’05). ACM Press, New York,
pp 47–56
121. Ware C, Hui D, Franck G (1993) Visualizing object oriented
software in three dimensions. In: Proceedings of the 1993 IBM
Centre forAdvanced Studies conference (CASCON’93), Toronto,
pp 612–660
122. Yoo I (2002) Visualizing windows executable viruses using self-
organizing maps. In: Proceedings of the 2004 ACM workshop
on visualization and data mining for computer security (Viz-
SEC/DMSEC’04), pp 82–89
123. Young P, Munro M (1998) Visualizing software in virtual real-
ity. In: Proceedings of the 6th international workshop on program
comprehension (IWPC’98), Ischia, pp 19–26
124. Zernik D (1995) Visualizing programs using graphs. In: Proceed-
ings of the 18th convention of electrical and electronics engineers
in Israel, pp 1.3.3/1–1.3.3/4
... We noticed that some papers did not fit in defined categories, as they do not always focus on an application field. It is the case for reviewing tool papers, evaluation methods [21], [29], [35], opinion papers [37] or papers dealing with SV as a whole [33], [34]. Besides, we extracted data from those offering shared ideas on particular discussed aspects. ...
... Regarding visualized artifacts, as SE generally deals with large amounts of data, it originates from heterogeneous sources such as Source Code Management (SCM) repositories, source code, Issue Tracking Systems (ITS), mailing and project discussion lists [30], [33], [34]. The main goal is to see how source code files changes over time. ...
... Caserta and Zendra [46] present the findings Conduct empirical studies to validate usefulness On existing visualizations, or the ones being developed, to add them values and speed up the integration process. Controlled experiment, unbiased subjects, quantitative measures [1]- [3], [7], [8], [10], [11], [21], [24], [26], [27], [30], [31], [33], [39], [41], [43], [44], [46], [47] 39.5% (19/48) ...
... Visualization as a programming learning media is not a new thing. Researchers have developed visualization tools to help students in learning algorithm and programming [4,9,10,22,23]. Because from the visual sense, humans more tend capture more information obtained than through other sense [28]. Visualization can support efficient and effective interaction for a variety of cognitive task such as analyzing, summarizing, and taking conclusions on the information obtained. ...
... There are so many software visualization system appear to be used with a particular purpose and continue growing every year [22]. Gra anin et al. [9] define the software visualization as a field to investigate with approaches and certain techniques that aims to represent graphics algorithm staticly or dynamicaly, code and data processed. Software visualization has the main purpose to analyzed program and development; to improve the understanding of invisible concept and how software works. ...
... Visualization is known to be an effective tool to understand patterns in large amount of information. In the field of software visualization, visualization algorithms and techniques can provide meaningful graphical representations for the code and data in a software artifact [16]. In particular, for the code clones and bugs, a well-designed visualization can provide more information regarding bug propagation, features associated with the bugs, and confidence into why some machine learning classifiers are working better than the others. ...
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Testing software is considered to be one of the most crucial phases in software development life cycle. Software bug fixing requires a significant amount of time and effort. A rich body of recent research explored ways to predict bugs in software artifacts using machine learning based techniques. For a reliable and trustworthy prediction, it is crucial to also consider the explainability aspects of such machine learning models. In this paper, we show how the feature transformation techniques can significantly improve the prediction accuracy and build confidence in building bug prediction models. We propose a novel approach for improved bug prediction that first extracts the features, then finds a weighted transformation of these features using a genetic algorithm that best separates bugs from non-bugs when plotted in a low-dimensional space, and finally, trains the machine learning model using the transformed dataset. In our experiment with real-life bug datasets, the random forest and k-nearest neighbor classifier models that leveraged feature transformation showed 4.25% improvement in recall values on an average of over 8 software systems when compared to the models built on original data.
... Software visualization (SV) for DP SV has long history in software engineering research and practice [47,48]. It has been used for visualizing code structure and features [49], code execution [50], and evolution [51], of large codebases in particular [52]. SV has also been applied to bug repositories, where it has been helpful in correlating bugs with code structure [53]. ...
... There exist surveys about software visualization in general [3] and about its various subfields, such as architecture [4] or awareness visualization [5]. Maletic et al. [6] presented a task-oriented taxonomy of software visualization. ...
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Thesis
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Thesis
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