Software Visualization

Software Software VisualizationVisualization

Maria TkatchenkoMaria Tkatchenko

Nov 8, 2004Nov 8, 2004

Software Software VisualizationsVisualizations As applied to the following tasksAs applied to the following tasks

– project managementproject management– execution tracingexecution tracing– code reviewcode review– structure explorationstructure exploration

Common themesCommon themes– abstractionabstraction– context + overviewcontext + overview– pattern explorationpattern exploration

Papers discussedPapers discussed

Software Visualization in the LargeSoftware Visualization in the Large, Ball and , Ball and Eick,1996Eick,1996

Execution Patterns in Object-Oriented Execution Patterns in Object-Oriented VisualizationVisualization, De Pauw, et.al.,1998, De Pauw, et.al.,1998

Managing Software with New Visual Managing Software with New Visual RepresentationsRepresentations, Chuah and Eick,1997, Chuah and Eick,1997

Program Auralization: Sound Enhancements Program Auralization: Sound Enhancements to the Programming Environmentto the Programming Environment, DiGiano , DiGiano and Baecker,1992and Baecker,1992

3D Representations for Software 3D Representations for Software VisualizationVisualization, Marcus, Feng, Maletic, 2003, Marcus, Feng, Maletic, 2003

Software Visualization in Software Visualization in the Largethe Large

Thomas A. Ball and Thomas A. Ball and Stephen G. Eick, 1996Stephen G. Eick, 1996

OverviewOverview

““Software is invisible”Software is invisible” Four visual representations of Four visual representations of

softwaresoftware– To help software engineers cope To help software engineers cope

with complexitywith complexity Case studies involving different Case studies involving different

development tasksdevelopment tasks

Main GoalsMain Goals

Increasing programmerIncreasing programmer– ProductivityProductivity– EfficiencyEfficiency

Improving program structureImproving program structure Scalable visualizationsScalable visualizations

Visualizing softwareVisualizing software

StructureStructure Run-time behaviorRun-time behavior Code itselfCode itself

Visual representationsVisual representations

Line representationLine representation Pixel representationPixel representation

– Show line as a pixelShow line as a pixel File summary representationFile summary representation

– File as a rectangle, inner time-seriesFile as a rectangle, inner time-series Hierarchical representationHierarchical representation

– Zoomable tree-mapZoomable tree-map

Pixel representationPixel representation

File summary File summary representationrepresentation

Critique (1)Critique (1)

““Hiding system complexity… Hiding system complexity… contributes to low programmer contributes to low programmer productivity”productivity”– Untrue of object-orientedUntrue of object-oriented– Good design, interfaces, Good design, interfaces,

documentation, etc. recover thisdocumentation, etc. recover this IDEs and special purpose tools IDEs and special purpose tools

now deal with the issue identifiednow deal with the issue identified


Need for textual visualization of a Need for textual visualization of a large system?large system?

Aim may be to condense too Aim may be to condense too much informationmuch information

Good way to visualize non-Good way to visualize non-functional properties of text if functional properties of text if metadata availablemetadata available

Execution Patterns in Object-Execution Patterns in Object-Oriented VisualizationOriented VisualizationWim De Pauw, David Wim De Pauw, David Lorenz, John Vlissides, and Lorenz, John Vlissides, and Mark Wegman.,1998Mark Wegman.,1998

OverviewOverview

Visualizing execution traces of Visualizing execution traces of object-oriented programsobject-oriented programs

Explore at different levels of Explore at different levels of abstractionabstraction

Classification of behavior into Classification of behavior into patternspatterns

Goals of tools:Goals of tools:– Explore structure of executionExplore structure of execution– Find areas to optimizeFind areas to optimize

Current execution Current execution tracingtracing TextualTextual

– Too much detail in outputToo much detail in output– Hard to controlHard to control

OO visualization systemsOO visualization systems– Microscopic – sequence of message Microscopic – sequence of message

sendssends– Macroscopic - cumulativeMacroscopic - cumulative

Very difficult to scaleVery difficult to scale

Execution pattern viewExecution pattern view

Observe any part of the programs Observe any part of the programs execution at various levels of detailexecution at various levels of detail– Detail on demandDetail on demand

Detect and present generalized Detect and present generalized patterns of executionpatterns of execution– Pattern subsumes many parts of the Pattern subsumes many parts of the

tracetrace Figure from paperFigure from paper

Interaction diagram Interaction diagram vs. execution patternvs. execution pattern

Useful featuresUseful features

Collapsing/expanding subtreesCollapsing/expanding subtrees More clear notation for interaction More clear notation for interaction

diagramsdiagrams Easy change in level of abstraction Easy change in level of abstraction

and viewand view Detection and collapsing of Detection and collapsing of

repetitionsrepetitions Tree operationsTree operations

– FlatteningFlattening– OverlayingOverlaying

FlatteningFlattening

Pattern detectionPattern detection

Not only reduces clutter, but Not only reduces clutter, but makes things explicitmakes things explicit

Similar vs. identicalSimilar vs. identical– Automatic pattern detection Automatic pattern detection

importantimportant– The slight differences often not that The slight differences often not that

important to the programmerimportant to the programmer Pattern matchingPattern matching

– AutomaticAutomatic– Tools for programmer to express Tools for programmer to express

similaritysimilarity

PatternsPatterns

IdentityIdentity Class Identity ***Class Identity *** Message StructureMessage Structure Depth-LimitingDepth-Limiting Repetition ***Repetition *** Polymorphism ***Polymorphism *** AssociativityAssociativity Commutativity ***Commutativity ***

Experimental resultsExperimental results

Uncover unexpected behaviorUncover unexpected behavior Help understand unfamiliar codeHelp understand unfamiliar code Improve performanceImprove performance

ContributionsContributions

Intuitive and scalable metaphorIntuitive and scalable metaphor Generalization of similar Generalization of similar

execution patternsexecution patterns Execution patterns allow to Execution patterns allow to

characterize system complexitycharacterize system complexity


Collapsing of repetition is a great Collapsing of repetition is a great ideaidea– Use for design as well as analysisUse for design as well as analysis

Good use of the OO programming Good use of the OO programming principles and metaphorprinciples and metaphor

Learning curve for distinguishing Learning curve for distinguishing patterns and classespatterns and classes


How often large-scale vs. local How often large-scale vs. local exploration of execution is exploration of execution is performedperformed

Library of patternsLibrary of patterns– Instead of language to express Instead of language to express

similaritysimilarity– How much can be captured with How much can be captured with

common patterns?common patterns?– Non-standard execution patternsNon-standard execution patterns

Managing Software with Managing Software with New Visual New Visual RepresentationsRepresentationsMei C. Chuah, Stephen Mei C. Chuah, Stephen G. Eick, 1997G. Eick, 1997

OverviewOverview

Managing: tracking and Managing: tracking and scheduling many resourcesscheduling many resources– Need a way to represent each oneNeed a way to represent each one

Way to view time-oriented Way to view time-oriented informationinformation

Glyphs to view summariesGlyphs to view summaries– Combinations of established viewsCombinations of established views– Interpret by prior knowledgeInterpret by prior knowledge

Issues in Project Data Issues in Project Data Management (1)Management (1) TimeTime

– Deadline, milestonesDeadline, milestones Large data volumesLarge data volumes

– UnstructuredUnstructured– Partition data and management Partition data and management

responsibilities hierarchicallyresponsibilities hierarchically

Issues in Project Data Issues in Project Data Management (2)Management (2) Diversity/varietyDiversity/variety

– Resources and their attributesResources and their attributes– Flexible visual representationsFlexible visual representations

Data <-> “real-world” Data <-> “real-world” correspondencecorrespondence– Data element to real-world entityData element to real-world entity– Glyphs group properties of a data Glyphs group properties of a data

element visuallyelement visually

Time-oriented Time-oriented informationinformation Traditional:Traditional:

– AnimationAnimation– Time-series plotTime-series plot

Variation on time-series plotVariation on time-series plot– TimeWheelTimeWheel– 3D-Wheel3D-Wheel

Show trendsShow trends

TimeWheel (1)TimeWheel (1)

Each object attribute a time-Each object attribute a time-seriesseries

Individual time-series laid out Individual time-series laid out around a circlearound a circle

Preattentively pick out objectsPreattentively pick out objects Small multiples show:Small multiples show:

– General trendGeneral trend– divergencesdivergences



Advantages over linear:Advantages over linear:– Reduce number of eye movementsReduce number of eye movements– Less susceptible to local patternsLess susceptible to local patterns– No ordering implication from readingNo ordering implication from reading– Higher information densityHigher information density

3D-Wheel (1)3D-Wheel (1)

Same as TimeWheel, use height Same as TimeWheel, use height to encode timeto encode time

Dominant time trend through Dominant time trend through shapeshape

Common problem of occlusionCommon problem of occlusion– Hard to identify divergences from Hard to identify divergences from

trendtrend

3D-Wheel (2)3D-Wheel (2)

InfoBug (1)InfoBug (1)

InteractiveInteractive Use animation to show at Use animation to show at

different times within the projectdifferent times within the project Small footprintSmall footprint Preattentive patternsPreattentive patterns



Glyph:Glyph:– Head – code types in componentHead – code types in component– Wings - # lines of code vs. # errorsWings - # lines of code vs. # errors– Body – size of componentsBody – size of components– Tail - # lines added and deleted, to Tail - # lines added and deleted, to

fix errors or add functionalityfix errors or add functionality

CritiqueCritique

Glyph seems like a good idea, but too Glyph seems like a good idea, but too complicated at timescomplicated at times– TailTail– Hard to compare when scaled downHard to compare when scaled down

Circular time-data looks good for Circular time-data looks good for patternspatterns

Would be nice to see used with a Would be nice to see used with a number of different systems, compare number of different systems, compare patternspatterns

Program Auralization: Program Auralization: Sound Enhancements to Sound Enhancements to the Programming the Programming EnvironmentEnvironment Christopher Christopher J. DiGiano and Ronald M. J. DiGiano and Ronald M. Baecker,1992Baecker,1992

OverviewOverview

Use of sound in a programming Use of sound in a programming environment, not in a specific environment, not in a specific applicationapplication

Auralization: use of non-speech Auralization: use of non-speech audio for supporting the audio for supporting the understanding and effective use understanding and effective use of computer programsof computer programs

Benefits of soundBenefits of sound

New channelNew channel– Don’t add clutter to visual displayDon’t add clutter to visual display– directionlessdirectionless

Varied across up to 20 Varied across up to 20 dimensionsdimensions

Logarithmic natureLogarithmic nature Already familiar with its meaningAlready familiar with its meaning

Program taxonomyProgram taxonomy

ExecutionExecution– Behaviour of a programBehaviour of a program

ReviewReview– ModulesModules– keywordskeywords

PreparationPreparation– Syntactic structureSyntactic structure

Execution (1)Execution (1)

Info about behaviour of the Info about behaviour of the programprogram– VariablesVariables– Internal state, control flowInternal state, control flow

Trend detectionTrend detection Can represent:Can represent:

– Values – data flowValues – data flow– Events – control flowEvents – control flow

Execution (2)Execution (2)

Classifications for values and Classifications for values and eventsevents– Common – typical structuresCommon – typical structures– Arbitrary – unpredictable elementsArbitrary – unpredictable elements– Internal – internal stateInternal – internal state

ValuesValues– Map to many sound dimensionsMap to many sound dimensions

EventsEvents– Patterns or “melodies” usefulPatterns or “melodies” useful

ReviewReview

Interactive exploration of codeInteractive exploration of code– Modules, keywordsModules, keywords

Alternative to indentation, code Alternative to indentation, code style,..style,..

Use “audio landmarks” to mark Use “audio landmarks” to mark important segmentsimportant segments

Recognize patterns when scrollingRecognize patterns when scrolling

PreparationPreparation

Syntactic structureSyntactic structure StagesStages

– Entering a programEntering a program– CompilationCompilation

Loop exampleLoop example– ScopeScope– scalabilityscalability


Interesting, yet-unexplored ideaInteresting, yet-unexplored idea Definitely would have benefited Definitely would have benefited

from presenting a user studyfrom presenting a user study Useful for pattern recognitionUseful for pattern recognition Hard to convince that it’s good for Hard to convince that it’s good for

anything but highest-level overviewanything but highest-level overview Utility for monitoring background Utility for monitoring background

activitiesactivities


Enhancement to visual, couldn’t Enhancement to visual, couldn’t replacereplace

No scalabilityNo scalability Couldn’t follow execution real-Couldn’t follow execution real-

timetime Workspace issuesWorkspace issues Real-life examples?Real-life examples?

3D Representations for 3D Representations for Software VisualizationSoftware VisualizationAndrian Marcus, Louis Andrian Marcus, Louis Feng, Jonathan I. Feng, Jonathan I. Maletic, 2003Maletic, 2003

OverviewOverview

Tool using 3D, texture, .. to represent Tool using 3D, texture, .. to represent multiple attributes in one viewmultiple attributes in one view

Visualization of large-scale software Visualization of large-scale software to assist in comprehension and to assist in comprehension and analysisanalysis

Categorize info to display important Categorize info to display important info more efficientlyinfo more efficiently

Visualization front-end, independent Visualization front-end, independent of source of dataof source of data

Dimensions of interestDimensions of interest

Tasks – why visualizeTasks – why visualize Audience – usersAudience – users Target – data sourceTarget – data source Representation – how to show Representation – how to show

datadata Medium – where displayedMedium – where displayed

Features (1)Features (1)

Separate visualization from data Separate visualization from data collectioncollection

Manipulation on a per-element basisManipulation on a per-element basis Users can develop own visualization Users can develop own visualization

metaphors based on tasksmetaphors based on tasks Function similar to another tool done Function similar to another tool done

7 years prior7 years prior

Features (2)Features (2)

Visual front-end – can be used Visual front-end – can be used with output of many analysis toolswith output of many analysis tools

Certain elements only suitable for Certain elements only suitable for certain data typescertain data types

Support for user needsSupport for user needs

Overview ***Overview *** ZoomZoom FilterFilter Details-on-demandDetails-on-demand Relate ***Relate *** HistoryHistory ExtractExtract

CritiqueCritique

Propose to develop a stereoscopic Propose to develop a stereoscopic display – not practical? display – not practical?

Visual elements only suitable for Visual elements only suitable for certain data – guidance to users?certain data – guidance to users?

Core components designed as an Core components designed as an application frameworkapplication framework– Extend with new mappings and Extend with new mappings and

visual elementsvisual elements

ConclusionsConclusions

Applying visualization to various Applying visualization to various aspects of software engineeringaspects of software engineering

Various channels - visual, audioVarious channels - visual, audio Building on existing ideasBuilding on existing ideas User studies and community User studies and community

acceptance?acceptance?

Documents

Software Visualization