visualizations for code metrics

Transcription

1 ThoughtWorks visualizations for code metrics NEAL FORD software architect / meme wrangler ThoughtWorks nford@thoughtworks.com 3003 Summit Boulevard, Atlanta, GA blog: memeagora.blogspot.com twitter: neal4d

2 housekeeping ask questions anytime download slides from nealford.com download samples from github.com/nealford

3 what was that? code_swarm point it to a subversion repository visualization of check-ins over time useful? cool!

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6 wtf s/min

7 external perspective is the software valuable to its users?

8 internal perspective how appropriate is the design? how amenable is emergent design? how easy is it to understand & extend? how maintainable is it? is it salvageable?

9 30,000 feet ground level

10 where are the defects?

11 which way do the messages flow?

12 where do the pictures come from? models created up front convey a vision but usually don t reflect reality generating a complete model for large systems is nearly impossible systems evolve locally, often uncontrolled the best picture very much depends on the question you are trying to answer need tools to create ad-hoc models more easily

13 1. select a meta-model a model that describes a model example: meta-model for a class diagram a class is a box with name, methods, fields,... available connectors: association, inheritance, aggregation rules: no circles in inheritance, etc.

14 common meta-models Metrics (Quantitative) Directed Graph M 1 xyz Foo Clas M1 M2 M3 Bar M 2 s Foo Bar M 1 Tree Process Model (e.g. Petri Net)

15 static analysis 2. inspection / instrumentation source code byte code dynamic analysis profiling, listen to messages, log files, network sniffer, etc.

16 3. mapping to the model example: messaging system capture send/receive actions Senders Comp. Channel A X B Y Receivers Comp. Channel C X C Y map onto directed graph Mapper Nodes: A, B, C Edges: X(A!C) Y(B!C) Graph Model

17 Graphviz 4. visualization &...

18 ...validation don t simply observe verify & alert enforce rules or best practices detect cycles islands on a dependency graph

19 the hawthorne effect

20 the hawthorne effect measure and let it be known that you are measuring

21 metrics

22 cyclomatic complexity measures complexity of a function V(G)= e - n + 2 V(G) = cyclomatic complexity of G e= # edges n= # of nodes

23 start 1 if (c1) f1() 3 f2() if (c2) nodes f3() 6 f4() edges end

24 chidamber & kemerer object-oriented metrics shyam r chidamber chris f kemerer easy but not terribly useful very useful

25 easy (but trivial) dit depth of inheritance tree # levels of inheritance noc number of children # immediate descendants npm number of public methods # public methods in class

26 very useful wmc rfc lcom cbo/ ce ca weighted methods/ class response for class lack of cohesion efferent couplings afferent couplings of cyclomatic complexity # of methods executed due to method call of sets of methods not shared via sharing fields of other classes this class uses (outgoing calls) of how many other classes use this class (incoming calls)

27 visualizations

28 source monitor freeware tool for gathering metrics metrics: lines, statements, % branches, calls, % comments, classes, methods/class, avg stmts/ method, max complexity, max depth, average depth, average complexity graphical user interface, windows only!

29 source monitor: kiviat graphs

30 source monitor: class summary

31 source monitor w/ c#

32 looking for... classes that violate several kiviat graph ranges really odd shapes

33 A project dedicated to making code metrics so widely understood, valuable, and simple that their use becomes ubiquitous, thus raising the quality of software across the industry.

34 panopticode parts code coverage with emma 1-line change to switch to cobertura checkstyle 1-line switch for custom rule sets jdepend code duplication using simian javancss aggregator & reports volatility treemaps

35 complexity treemap

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37 code coverage

38 looking for... 20,000 foot view along a single dimension simple view of one dimension information radiators

39 size & complexity pyramid developed at Universities of Berne and Lugano shows key metrics and their relationships allows comparison to industry standards created by iplasma tool from source code

40 pyramid 5.75 NOP NOC NOM NOM LOC CALLS 0.40 CYCLO FANOUT

41 iplasma + Struts

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43 vuze

44 looking for... adherence to industry standards low number of lines / method (see composed method pattern) low cyclomatic complexity / line

45 GraphViz

46 e v e n d o t t l i s t f i l e

47 output

48 generating dot files

49 untangling jars jar analyzer Kirk Knoernschild

50 xml output

51 t r a n s f o r m e d

52 graphical struts 1.0

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55 looking for... not that! small number of oneway dependencies no rats nests no cycles

56 Vizant ant task to create a GraphViz DOT file from an ant build file

57 ant 1.5

58 log4j

59 tomcat 3.3.1

60 from= dist

61 to= prepare

62 look for... hot spots more even distribution networks around common dependent elements think about extracting via macrodef

63 SpringViz XSLT => DOT for spring dependencies

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66 SpringViz

67 look for... regularity symmetry overloaded dependencies isolated pockets

68 toxicity chart provides easy to compare overview of quality created with checkstyle + excel

69 toxicity chart SessionFactory Utils.java AbstractBeanFactory.java BeanWrapperImpl.jav a DispatcherServ let.java SchedulerFactory Bean.java AntPathMatcher.jav a SQLErrorCodeSQLExceptionTranslator.jav a HibernateTemplate.jav a ReloadableResourceBundleMessageSource.jav a PropertiesBeanDef initionreader.jav a StatementCreatorUtils.java Lazy ConnectionDataSourceProxy.java Def aultmessagelistenercontainer.java JdoTransactionManager.jav a TopLinkTransactionManager.jav a ScriptFactory PostProcessor.java TransactionAwareConnectionFactory Proxy.java NumberUtils.jav a HibernateAccessor.jav a SpringSessionSy nchronization.jav a BeanDef initionvalueresolv er.java ExtendedEntity ManagerCreator.jav a ParameterMethodNameResolv er.java CallableStatementCreatorFactory.java BeanFactory AspectJAdvisorsBuilder.java CustomizableTraceInterceptor.jav a AbstractXsltView.jav a GenericCollectionTy peresolv er.java ArgumentConv ertingmethodinv oker.java SharedEntity ManagerCreator.jav a FreeMarkerConf igurationfactory.java SelectedValueComparator.jav a MockHttpServ letrequest.java FrameworkPortlet.jav a ResourceArray Property Editor.java AspectJWeav ermessagehandler.java MethodMapTransactionAttributeSource.jav a SingleConnectionFactory.java MessageListenerAdapter.jav a JdoTemplate.jav a DataSourceUtils.java Velocity View.jav a AbstractMessageListenerContainer.java SqlLobValue.jav a PortletRequestHandledEv ent.java JdbcOperations.jav a TxAdv icebeandef initionparser.java ArgTy pepreparedstatementsetter.jav a Ref reshablepagedlistholder.java AbstractJasperReportsSingleFormatView.java ClassUtils.java Simpl Message.jav a JmsTransactionManager.jav a TransactionAttributeEditor.jav a Def aultbeandef initiondocumentreader.java AbstractInterceptorDrivenBeanDefinitionDecorator.java ResultSetWrappingSqlRowSet.jav a HsqlMaxValueIncrementer.jav a CodebaseAwareObjectInputStream.jav a AbstractSingletonProxy FactoryBean.java LocalSlsbInv okerinterceptor.java BeansDtdResolv er.java AbstractMessageSource.jav a AbstractDependency InjectionSpringContextTests.java TomcatInstrumentableClassLoader.java LocalContainerEntity ManagerFactoryBean.java ResourceEntity Resolver.java RedirectView.jav a HtmlCharacterEntityReferences.java AbstractPathMapHandlerMapping.jav a AspectJPrecedenceComparator.java ResourceServ let.java Adv isedsupport.jav a EhCacheFactory Bean.java CustomCollectionEditor.java CommonsMultipartFile.jav a OpenEntity ManagerInViewFilter.jav a TopLinkInterceptor.jav a MethodInv okingjobdetailfactorybean.java Def aultnamespacehandlerresolver.java XmlValidationModeDetector.jav a GenericFilterBean.jav a HessianServ iceexporter.java Property AccessorUtils.java InstantiationModelAwarePointcutAdv isorimpl.java BooleanExpressionComplexity ClassDataAbstractionCoupling ClassFanOutComplexity CyclomaticComplexity FileLength MethodLength NestedIfDepth AnonInnerLength ParameterNumber MissingSwitchDefault TreeWalker

70 test to code ratio Lines of unit test code per line of production code /4/06 15/4/06 29/4/06 13/5/06 27/5/06 10/6/06 24/6/06 8/7/06 22/7/06 5/8/06 19/8/06 2/9/06 16/9/06 30/9/06 14/10/06 28/10/06 11/11/06 25/11/06 9/12/06 23/12/06 6/1/07 20/1/07 3/2/07 17/2/07 3/3/07 17/3/07 31/3/07 14/4/07 28/4/07 12/5/07 26/5/07 9/6/07 23/6/07 7/7/07 21/7/07 4/8/07 18/8/07 Releases Unit test LOC/LOC created using unix tools + excel

71 cc / loc / releases

72 look for... notifications along your key dimension toxicity: high-spikes test-to-code ratio: higher is better complexity / loc: trends deltas more interesting than raw numbers

73 Unveiling the beauty of statistics for a fact based world view. time-based statistical view of chart data founded in Stockholm by Ola Rosling, Anna Rosling Rönnlund and Hans Rosling now realized in the google spreadsheet motion gadget

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75 the data

76 motion chart gadget

77 look for... time-based trends odd outliers along dimensions symmetry fluidity

78 CodeCrawler

79 CodeCrawler

80 CodeCrawler academic graphical metrics tool language independent written in VisualAge Smalltalk based on the Moose platform quirky but powerful

81 x-ray graduate student project written by Jacopo Malnati ( open-source software visualization plug-in for eclipse provides system complexity view, class & package dependency view model of the underlying Java project can be triggered and used by other plug-ins

82 x-ray visualizing itself through via system complexity view

83 using x-ray install the plug-in choose the Analyze Current Project action from the package explorer x-ray creates textual information and actions visualizations characterized by entities positioned according to layouts and criterions

84 actions # packages # methods open selected classes show/hide nodes show dependencies project name lines of code color tag # classes snapshot image show/hide package content

85 polymetric views system complexity view class dependency view package dependency view

86 system complexity view

87 system complexity view tries to illustrate disharmonies in the design and implementation of a system. identify big nodes (compared to the others) anomalies of shape (provided by the inheritance tree) view provides several different dimensions of metrics

88 positional metrics

89 system complexity view

90 color metrics

91 system complexity view

92 x-ray itself Azureus 3.0 (more than 500,000 lines of code)

93 dependencies outgoing incoming

94 class & package dependency views

95 class dependency view

96 package dependency

97 Azureus packages

98 filtering (< 30 weight)

99 proximity alert

100 look for... towers (=> lots of code, lots of methods) tangled dependencies exuberant responsibility natural partitions balance

101 10,000 ft view (literally) CodeCity by Richard Wettel

102 CodeCity integrated environment for software analysis software systems are visualized as interactive, navigable 3D cities written in VisualWorks Smalltalk, atop the Moose platform classes => buildings packages => districts

103 citylyzer

104 Citylyzer written atop x-ray inspired by CodeCity building height => number of methods width/length => number of attributes packages => districts

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109 look for... real cityscape buildings that wouldn t exist in the real world overly crowded neighborhoods abandoned parts of town would you live there?

110 metrics + agility wire metrics & analysis into continuous integration manually check often discuss on iteration boundaries fail the build with: xpath expressions & plugins jdepend-like unit tests

111 summary intermediate altitude information radiators single dimensions compelling evidence cool!

112 ThoughtWorks? s please fill out the session evaluations samples at github.com/nealford NEAL FORD software architect / meme wrangler ThoughtWorks This work is licensed under the Creative Commons Attribution-Share Alike 3.0 License. nford@thoughtworks.com 3003 Summit Boulevard, Atlanta, GA blog: memeagora.blogspot.com twitter: neal4d