Java source code analysis for better testing

ICESCRUM
Application ICESCRUM2

Audit Report
2010-02-10

This document is a sample audit report produced automatically
from the results of the analysis of the application on the Kalistick platform.
It does not include any specific comments on the results.

Its purpose is to serve as a model to build custom reports,
it illustrates the ability of the platform to render a clear
and comprehensible quality of an application.

This document is confidential and is the property of Kalistick.
It should not be circulated or modified without permission.

Kalistick
13 av Albert Einstein
F-69100 Villeurbanne
+33 (0) 486 68 89 42
contact@kalistick.com
www.kalistick.com

Code audit of IceScrum2 application 2010-02-10

1 Executive Summary
The Quality Cockpit uses static analysis techniques: it does not execute the application, but analyzes the
elements that compose it (code, test results, architecture ...). The results are correlated, aggregated and
compared within the project context to identify risks related to quality. This report presents the results.

Variation compared to the objective

This chart compares the current status of the project
to the objectives set for each quality factor.

The goal, set at the initialization of the audit,
represents the importance of each quality factor. It
is intended to define the rules to follow during
development and the accepted tolerance.

Rate of overall non-compliance

This gauge shows the overall level of quality of the
application compared to its objective. It displays the
percentage of the application (source code)
regarded as not-compliant.

According to the adopted configuration, a rate
higher than 15% indicates the need for further
analysis.

Origin of non-compliances

This graph identifies the technical origin of
detected non-compliances, and the main areas of
improvement.

According to elements submitted for the analysis,
some quality domains may not be evaluated.

Confidential – This document is the property of Kalistick 2/58


Report Organization
This report presents the concepts of Quality Cockpit, the goal and the associated technical requirements
before proceeding with the summary results and detailed results for each technical area.

1 Executive Summary ...................................................................................................................................... 2
2 Introduction .................................................................................................................................................. 4
2.1 The Quality Cockpit............................................................................................................................... 4
2.2 The analytical........................................................................................................................................ 4
3 Quality objective........................................................................................................................................... 7
3.1 The quality profile ................................................................................................................................ 7
3.2 The technical requirements ................................................................................................................. 7
4 Summary of results..................................................................................................................................... 10
4.1 Project status ...................................................................................................................................... 10
4.2 Benchmarking ..................................................................................................................................... 13
4.3 Modeling application.......................................................................................................................... 17
5 Detailed results........................................................................................................................................... 19
5.1 Detail by quality factors...................................................................................................................... 19
5.2 Implementation .................................................................................................................................. 20
5.3 Structure ............................................................................................................................................. 24
5.4 Test ..................................................................................................................................................... 31
5.5 Architecture ........................................................................................................................................ 38
5.6 Duplication ......................................................................................................................................... 39
5.7 Documentation................................................................................................................................... 41
6 Action Plan.................................................................................................................................................. 43
7 Glossary ...................................................................................................................................................... 45
8 Annex .......................................................................................................................................................... 47
8.1 Cyclomatic complexity........................................................................................................................ 47
8.2 The coupling ....................................................................................................................................... 49
8.3 TRI and TEI .......................................................................................................................................... 50
8.4 Technical Requirements ..................................................................................................................... 52



2 Introduction

2.1 The Quality Cockpit
This audit is based on an industrialized process of code analysis. This industrialization ensures reliable results
and easily comparable with the results of other audits.

The analysis process is based on the "Quality Cockpit" platform, available through SaaS1 model
(https://cockpit.kalistick.com). This platform has the advantage of providing a knowledge base unique in that
it centralizes the results from statistical analysis of millions code lines, enriched continuously with new
analyses. It allows performing comparative analysis with other similar projects.

2.2 The analytical
The analysis focuses on the code of the application (source code and binary code), for Java (JEE) or C# (. Net)
technologies. It is a static analysis (without runtime execution), supplemented by correlation with
information from development tools already implemented for the project: version control system, unit
testing frameworks, code coverage tools.

The results are given through an analytical approch based around three main dimensions:

 The quality factors, which determine the nature of the impact of non-compliances detected, and the
impact on the quality of the application
 The quality domains, which specify the technical origin of non-compliances
 The severity levels, which positions the non-compliances on a severity scale to characterize their
priority

1
Software as a Service: application accessible remotely via Internet (using a standard browser)



2.2.1 The quality factors
The quality factors standardize a set of quality attributes which should claim the application according to ISO
912623:

 Maintainability. Ability of software to be easily repaired, depending on the effort required to locate,
identify and correct errors.

 Reliability. Ability of software to function properly in making the service expected in normal
operation.

 Changeability. Ability of software to be able to evolve, depending on the effort required to add,
delete, and modify the functions of an operating system.

 Security. Ability of software to operate within the constraints of integrity, confidentiality and
traceability requirements.

 Transferability. Ability to perform maintenance and evolution of software by a new team separate
from the one which developed the original software.

 Efficiency. Relationship between the level of software performance and the number of resources
required to operate in nominal conditions.

2.2.2 The quality domains
The quality domains determine the nature of problems according to their technical origin. There is six of it:

 Implementation. The problems inherent in coding: misuse of language, potential bugs, code hard to
understand ... These problems can affect one or more of the six quality factors.

 Structure. Problems related to the code organization: methods too long, too complex, with too many
dependencies ... These issues impact maintainability and changeability of the application.

 Test. Describes how the application is tested based on results of unit tests (failure rate, execution
time ...) but also of the nature of the code covered by the test execution. The objective is to ensure
that the tests cover the critical parts of the application.

2
ISO/IEC 9126-1:2001 Software engineering — Product quality — Part 1: Quality model :
http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=22749
3
The analysis focuses on a subset of ISO 9126 in order to focus on controllable dimensions automatically.



 Architecture. Problems with the software architecture of the application. The platform allows the
definition of an architectural model to modularize the application into layers or components and
define communication constraints between them. The analysis identifies in the code all the calls
which do not satisfy these constraints, to detect the maintainability, changeability and security risk
levels.

 Documentation. Problems related to lack of documentation in the code. This area primarily impacts
the transferability of code.

 Duplication. Identification of all significant copy-pastes in the application. They impact reliability,
maintainability, transferability and changeability.

2.2.3 Severity levels
The severity levels are intended to characterize the priority of correction of non-compliances. This priority
depends on the severity of the impact of non-compliance, but also on the effort required for correction:
some moderately critical problems might be marked with a high level of severity because of the triviality of
their resolution.

To simplify interpretation, the severity levels are expressed using a four-level scale. The first is an error, the
others are warnings, from most to least severe:

 Forbidden

 Highly inadvisable

 Inadvisable

 To be avoided

Compared to the Forbidden level, other levels of severity are managed with a tolerance threshold, which
increases inversely with gravity.



3 Quality objective
One of distinctive features of "Quality Cockpit" is to perform the analysis according to real needs of the
project in terms of quality, in order to avoid unnecessary efforts and to ensure greater relevance of quality
risks.

These requirements are formalized by defining the "quality profile" of the application, which characterizes
the quality levels expected on each of the six main quality factors. This profile is then translated as "technical
requirements" which are technical rules to be followed by the developers.

3.1 The quality profile
For this audit, the profile is established as follows:

See the Quality Cockpit

3.2 The technical requirements
Based on the above quality profile, technical requirements have been selected from the “Quality Cockpit”
knowledge base. These technical requirements cover the six quality domains (implementation, structure,
testing, architecture, documentation, duplication) and are configured according to the quality profile
(thresholds, levels of severity ...). The objective is to ensure a calibration of requirements that ensures the
highest return on investment.



Here are the details of these technical requirements:

Domain Rule Explanation, goal and possible thresholds
- According to your profile, between 150 and 200 rules were selected. They
Implementation

are exhaustively presented in the appendix of the report (8.4.1
Implementation rules).

Objective: avoid bad practices and apply best practices related to the
technology used.

Size of methods Number of statements. This measure is different from the number of lines
of code: it does not include comment lines or blank lines but only lines with
at least one statement.

Objective: avoid processing blocks difficult to understand.

The threshold for the project is:
 Number of lines: 100

Complexity of methods Cyclomatic complexity of a method. It measures the complexity of the
control flow of a method by counting the number of independent paths
covering all possible cases. The higher the number, the harder the code is to
maintain and test.
Structure

Objective: avoid processing blocks difficult to understand, not testable and
which tend to have a significant rate of failure.

The threshold for the project is:
 Cyclomatic complexity: 20

Complexity and Identifies methods difficult to understand, test and maintain because of
coupling of methods moderate complexity (cyclomatic complexity) and numerous references to
other types (efferent coupling).

Objective: avoid processing blocks difficult to understand and not testable.

The thresholds for the project are:
 Efferent coupling: 20



Domain Rule Explanation, goal and possible thresholds
Test coverage methods Rate of code coverage for a method. This metric is standardized by our
platform based on raw measures of code coverage when they are provided
in the project archive.

This rule requires a minimum level of testing (code coverage) for each
method of the application according to the TRI (TestRelevancyIndex); TRI
for each method assesses the risk that it contains bugs. His calculation takes
into account the business risks defined for the application.
Test

Objective: focus the test strategy and test efforts towards sensitive areas of
the application and check them. These sensitive areas are evaluated
according to their propensity to contain bugs and according to business
risks defined for the application.

Details of the thresholds are provided in the annex to the report (8.4.2 Code
coverage).

Rules defined See the architecture model defined for the application to check architecture
specifically through the constraints.
Architecture

architecture model.
Objective: ensure that developments follow the expected architecture
model and do not introduce inconsistencies which could be security holes,
maintenance or evolution issues.

Note: violations of architecture are not taken into account in the calculation
of non-compliance.

Header documentation Identifies methods of moderate complexity which have no documentation
of methods header. The methods considered are those whose cyclomatic complexity
Documentation

and number of statements exceed the thresholds defined specifically for
the project.

Objective: ensure that documentation is available in key processing blocks
to facilitate any changes in the development team (transferability).

The thresholds for the project are:
 Number of lines: 50

Detection of Duplicated blocks are invalid beyond 20 Statements
Duplication

duplications
Objective: detect identical blocks of code in several places in the
application, which often causes inconsistencies when making changes, and
which are factor of increased costs of testing and development.



4 Summary of results
This chapter summarizes the status of the project using global indicators. These indicators measure the
intrinsic quality of the project, but also compare its situation to other projects using “Quality Cockpit”
knowledge base.

4.1 Project status
The following indicators are related to the intrinsic situation of the project.

4.1.1 Rate of overall non-compliance
The rate of non-compliance measures the percentage of application code considered as non-compliant.


Specifically, this represents the ratio between the total number of statements, and the
number of statements in non-compliant classes. A class is considered as non-compliant if at least
one of the following statements is true:

- A forbidden non-compliance is detected in the class
- A set of non-compliances highly inadvisable, inadvisable, or to be avoided are detected in
the class, and beyond a certain threshold. This calculation depends on the severity of each non-
compliance and on the quality profile that adjusts the threshold of tolerance.



4.1.2 Deviation from target
This chart summarizes the difference between the target as represented by the quality profile and the
current status of the project. This difference is shown for each quality factor:


The level of non-compliance is calculated for each quality factor, and then weighted by the
level of requirements set for the related quality factor.

Quality theme Classes Significant non-compliances % application
Changeability 27 107 29%
Efficiency 7 8 5%
Maintainability 40 216 41%
Reliability 40 136 37%
Security 0 0 0%
Transferability 32 131 38%
[Total] 53 264 49.99%

Detailed results specify for each quality factor: the number of non-compliant classes, the
number of violations for selected rules, and the percentage of application code involved in non-
compliant classes.



4.1.3 Origin of non-compliances
The following chart shows the distribution of non-compliances according to their technical origin:


This chart compares each field according to the impact of rules that are associated with
the quality of the application. The impact is measured from the number of statements in classes
non-compliant.

4.1.4 Volumetry
The following table specifies the volume of the analyzed application:

Metric Value Trend
Line count 47671 +14.93%
Statement count 24034 +18.36%
Method count 4384 +13.75%
Class count 230 +10.58%
Package count 43 +4.88%


A "line" corresponds to a physical line of a source file. It may involve a white line or a
comment line. A "statement" is a primary unit of code, it can be written on multiple lines, but
also a line may contain multiple statements. For simplicity, a statement is delimited by a
semicolon (;) or a left brace ({).



4.2 Benchmarking
The “Quality Cockpit" knowledge base allows a comparative analysis of the project with other projects
reviewed on the platform. The objective is to measure its level of quality compared to an overall average.

This comparison benchmarking is proposed in relation to two categories of projects:

 The “Intra-Cockpit” projects: projects analyzed continuously on the platform, therefore, with a
quality level above average (a priori)
 The “Extra-Cockpit” projects: the projects reviewed from time to time on the platform in audit
mode, so with a highly heterogeneous quality.

Note: each project having its own specific quality profile, benchmarking does not take in account project
configuration, but uses instead raw measures.

4.2.1 Comparison on implementation issues
The chart below shows the status of the project implementation compared to the Extra-Cockpit projects,
therefore analyzed promptly on the platform. For each level of severity, the quality of the project is
positioned relative to others:




The project is positioned relative to other projects according to the rate of violations for
each rule. The distribution is based on the quartile method, three groups are distinguished,
"Better": the 25% best projects, "On the average": the 50% average projects, "Worse": the 25%
worse projects. This information is then synthesized by level of severity.

The implementation rules compared are not necessarily the same as quality profiles, but
here we compare the rules according to their severity level set for each project.

The following graph provides the same analysis, but this time with the Intra-Cockpit projects, analyzed
continuously on the platform, so with a level of quality normally above average since detected violations
should be more corrected:


A dominant red color indicates that the other projects tend to correct the violations
detected on this project.



4.2.2 Mapping the structure
The following chart compares the size of the methods of the current project with those of other projects,
"Intra-Cockpit" and "Extra-Cockpit", comparing the ratio of the application (as a percentage of statements)
which is located in processing blocks (methods) with a high number of statements:


A significant proportion of the application in the right area is an indicator of greater
maintenance and evolution costs.
NB: The application analyzed is indicated by the term "Release".



A similar comparison is provided for the cyclomatic complexity4 of methods, comparing the proportion of the
application (as a percentage of statements) that is located within complex methods:


A significant proportion of the application in the right area shows not only greater
maintenance and evolution costs, but also problems of reliability because this code is difficult to
test.

4.2.3 Comparison of main metrics
The following table compares the project with other projects, "Intra-Cockpit" and "Extra-cockpit", on the
main metrics related to the structure of the code. Recommended interval values are provided for
information purposes.

Metric Project Extra-Cockpit Intra-Cockpit Recommended
interval
Classes per package 5.35 7.57 50.68 6 - 26
Methods per class 19.06 10.71 8.74 4 - 10
Statements per method 5.48 8.05 7.26 7 - 13
Cyclomatic complexity per statement 0.34 0.3 0.29 0.16 - 0.24


4
Cyclomatic complexity measures the complexity of the code, and thus its ability to test it,
cf.http://classes.cecs.ucf.edu/eel6883/berrios/notes/Paper%204%20(Complexity%20Measure).pdf



4.3 Modeling application
To facilitate understanding of analysis results, the application is modeled in two ways: a functional
perspective to better identify the business features of the application and link them to the source code, and
a technical perspective to verify the technical architecture of the application.

These models are built using the modeling wizard available in the Cockpit. You can modify these templates
on the pages Functional modelization et Technical Architecture (depending on your user rights).

4.3.1 Functional model
The functional model represents the business view of application, which may be understood by all project
members.


The functional model is composed of modules, each one representing a business feature,
or a group of functionalities. These modules have been identified from a lexical corpus generated
from the application code which allows isolating the business vocabulary of the application.

4.3.2 Technical model
The technical model represents the technical architecture of the application code. The idea is to define a
target architecture model, which identifies the layers and / or technical components within the application,
and sets constraints to allow or prohibit communications between each of these elements.



The aim is threefold:

 Homogenize the behavior of an application. For example, to ensure that the logging traces are
written through a specific API, that data accesses pass through a dedicated layer, that some third-
party library is only used by specific components ...

 Ensure tightness of some components to facilitate their development and limit unintended
consequences, but also make them shareable with other applications. Dependency cycles are for
instance forbidden.

 Avoid security flaws for example by ensuring that calls to data layer always pass through a business
layer in charge of validation controls.

Results of the architecture analysis are provided in chapter 5.5 Architecture.


Green arrows formalize allowed communications between modules, while red arrows
formalize forbidden communications.



5 Detailed results
This chapter details the results by focusing, for each quality domain, non-compliant elements.

5.1 Detail by quality factors
The histogram below details the non-compliance rate for each quality factor, displaying also the number of
non-compliant classes. As a reminder, the rate of non-compliance is based on the number of statements
defined in non-compliant classes compared to the total number of statements in the project.

These rates of non-compliance directly depend on the quality profile and on the level of requirements that
have been selected:


Same class may be non-compliant on several factors, the total does not necessarily
correspond to the sum of the factors.



5.2 Implementation
Implementation domain covers the rules related to coding techniques. Unlike other domains, these rules are
often specific to the characteristics of a language (Java / C#). They identify, for example:

 Potential bugs: uninitialized variables, concurrency issues, recursive calls ...
 Optimizations in terms of memory or CPU
 Security vulnerabilities
 Obsolete code
 Code deviating from recommended standards
 ...

Implementations rules are the most numerous of the technical requirements. They are called "practice".

5.2.1 Breakdown by severity
The objective of this indicator is to identify the severity of the practices that led to the invalidation of the
classes. Here, severity is divided in two levels: forbidden practices (Forbidden security level) and inadvisable
practices (Highly inadvisable, Inadvisable and To be avoided security levels).

The following pie compares the number of non-compliant classes in implementation, according to the
practices that participated in this invalidation:

 When a class only violates forbidden practices, it is in the group “Forbidden practices”
 When a class only violates inadvisable practices, it is in the group “Inadvisable practices”
 Otherwise, the class violates practices of both categories and is in the group “Inadvisable and
forbidden practices”




The effort of correction related to forbidden practices is generally less important compared
to lower severities: a single violation is sufficient to cause a forbidden non-compliance when
several inadvisable practices are needed to cause non-compliance, depending on tolerance
thresholds.

The table below completes the previous graph by introducing the concept of “Significant non-compliance”. A
significant violation is a violation whose correction can fix fully or partially the non-compliance of a class.
Indeed, due to tolerance thresholds associated with levels of severity, the correction of some violations has
no impact on the non-compliance of the class.

Severity Significant non- New non- Corrected non- Other non-
compliances compliances compliances compliances
Forbidden 14 3 2 0
Highly inadvisable 71 29 7 70
Inadvisable 44 48 4 29
To be avoided 35 26 10 107

The columns "New non-compliance" and "Corrected non-compliances" are only relevant if
the audit follows a previous audit.



5.2.2 Practices to fix in priority
The two following tables provide a list of forbidden practices and highly inadvisable practices detected in the
application. These are generally the rules to correct first.

These tables provide for each practice the number of new non-compliances (if a previous audit has been
done), the total number of non-compliances for this practice, the number of non-compliant classes where
this practice has been detected and the percentage of statements of these classes compared to the overall
number of statement in the project.

These figures help to set up an action plan based on the impact associated with each practice.

5.2.2.1 Forbidden practices

Practice New Non- NC %
compliances classes application
DontUseNewToInstantiateIntegers 0 6 5 2.33%
AlwaysDeclareCloneableInterfaceWhenImplementingC 3 3 3 2.01%
loneMethod
AlwaysSynchronizeDateFormatter 0 1 1 1%
DontUseNewToInstantiateStrings 0 1 1 2.61%
MisplacedNullCheck 0 1 1 1%
NPEAlwaysThrown 0 1 1 1%
UseAppendMethodForStringBuffer 0 1 1 1%


5.2.2.2 Practice highly inadvisable

Practice New Non- NC classes %
compliances application
TraceErrorsWithLogger 20 80 28 33.98%
NeverMakeCtorCallInnerMethod 3 27 18 26.38%
UseLoggerRatherThanPrintMethods 4 27 7 9.47%
DontAssignVariablesInOperands 2 5 2 3.04%
DontIgnoreMethodsReturnValue 0 1 1 1.56%
OverrideEqualsWhenImplementingCompareTo 0 1 0 1%


5.2.3 Classes to fix in priority on the implementation issues
The two following tables provide an additional view about the impact of implementation issues in listing the
main classes involved in forbidden practices or highly inadvisable practices.



For each class is associated the number of existing violations (forbidden or highly inadvisable practices), the
number of new violations (if a previous audit has been done), and the compliance status of the class.

5.2.3.1 Classes with forbidden practices

Class NC New Non- Instructions
compliances
icescrum2.dao.model.impl.RemainingEstimationArray Yes 0 2 74
icescrum2.dao.model.impl.Sprint Yes 1 2 218
icescrum2.service.chart.PointBurnupChartProduct Yes 0 2 121
icescrum2.presentation.app.chat.PrivateChat Yes 0 1 184
icescrum2.service.impl.HibernateManagerImpl Yes 0 1 76
icescrum2.dao.impl.ProductDao Yes 0 1 69
icescrum2.dao.impl.UserDao Yes 0 1 76
icescrum2.dao.model.ISprint Yes 1 1 56
icescrum2.presentation.model.SprintImpl Yes 1 1 208
icescrum2.service.impl.ExportXMLServiceImpl Yes 0 1 628




5.2.3.2 Classes with practice highly inadvisable

Class NC New Non- Instructions
compliances
icescrum2.service.impl.RepositoryServiceImpl Yes 0 13 51
icescrum2.service.impl.ExportPDFServiceImpl Yes 1 9 455
icescrum2.service.impl.HibernateManagerImpl Yes 0 5 76
icescrum2.listeners.IS2ServletListener Yes 0 4 20
icescrum2.presentation.broadcast.RenderableSession Yes 0 4 110
icescrum2.service.chart.BurndownChartProduct Yes 0 4 172
icescrum2.service.chart.GlobalChartTest Yes 0 4 122
icescrum2.service.impl.ConfigurationServiceImpl Yes 1 4 103
icescrum2.service.impl.ExportXMLServiceImpl Yes 0 4 628
icescrum2.service.impl.ImportXMLServiceImpl Yes 0 4 482
icescrum2.service.impl.UserServiceImpl Yes 0 4 75
icescrum2.presentation.app.productbacklog.ProductBacklogUI Yes 2 3 817
icescrum2.service.chart.BurnupChartProduct Yes 0 3 184
icescrum2.service.chart.PointBurnupChartProduct Yes 0 3 121
icescrum2.service.impl.ExportPDFSprint Yes 3 3 97
icescrum2.presentation.app.product.ProductUI Yes 0 2 375
icescrum2.dao.impl.ExceptionManager No 0 2 103
icescrum2.dao.impl.ProblemDao No 0 2 51
icescrum2.filters.OpenSessionInViewPhaseListener No 0 2 97


5.3 Structure
The Structure domain targets rules related to the code structure, for example:

 The size of methods
 The cyclomatic complexity of methods
 Coupling, or the dependencies of methods towards other classes

The objective is to ensure that the code is structured in such a way that it can be easily maintained, tested,
and can evolve.

These rules are “metric”. They measure values (e.g. A number of statements) and are conditioned by
thresholds (e.g. 100 statements / method). Only metrics on which developers are able to act are presented
here. They apply to all methods.



5.3.1 Typology of structural problems
This histogram shows for each rule of structure domain number of non-compliance (thus methods) and the
percentage of related statements compared to the total number of statements in the application:


The percentage of statements shown is interesting since there is often only a few methods
concentrating a large part of the application code.

When some rules have been configured to be excluded from the analysis, they are
displayed in this graph but without any results.

One method may be affected by several rules; therefore, the total does not correspond to
the sum of numbers.

The following table completes this view by introducing the number of new violations and the number of
violations corrected in the case where a previous audit was conducted:

Anomaly Significant non- New non- Corrected non- NC
compliances compliances compliances rate
Statement count higher than 100 2 1 0 1%
Cyclomatic complexity higher than 20 14 4 0 3%




5.3.2 Mapping methods by size
The histogram below shows a mapping of methods according to their size. The size is expressed in number of
statements to ignore the writing styles conventions.

The last interval identifies the methods with a number of statements which exceeds the threshold. These
methods are considered non-compliant because they are generally difficult to maintain and extend, and also
show a high propensity to reveal bugs because they are difficult to test.

The percentage of statements is provided because larger methods usually focus a significant part of the
application:


The following table details the main non-compliant methods identified in the last interval of the previous
graph:



Method Instructions Lines Complexity New
violation
icescrum2.service.impl.ExportPDFServiceImpl.addRelea 131 227 38 New
sePlan ( icescrum2.dao.model.IUser, int[], int[],
icescrum2.dao.model.IProduct)
icescrum2.service.impl.ClicheServiceImpl.createCliche ( 208 343 42
icescrum2.dao.model.IProduct, java.util.Date)

5.3.3 Mapping methods by complexity
The histogram below shows a mapping of methods according to their cyclomatic complexity (see 8.1
Cyclomatic complexity).

Cyclomatic complexity is a measure aiming to characterize the complexity of a block of code, by identifying
all possible execution paths. This concept has been standardized by Mc Cabe5, but several calculation
methods exist. The one used here is the most popular and the simplest: it counts the number of branching
operators (if, for, while,? ...) and conditions (??, && ...).

The last interval identifies methods whose complexity exceeds the threshold. These methods are considered
non-compliant for the same reasons as for the long methods: they are generally difficult to maintain and
extend, and also show a high propensity to reveal bugs.

The percentage of statements and the percentage of complexity are provided because the most complex
methods generally focus a significant part of the application.


5
1976, IEEE Transactions on Software Engineering: 308–320.
http://classes.cecs.ucf.edu/eel6883/berrios/notes/Paper%204%20(Complexity%20Measure).pdf.



The following table details the main non-compliant methods identified in the last interval of the previous
graph:

Method Instructions Lines Complexity New
violation
icescrum2.service.impl.ExportPDFServiceImpl.addRelea 131 227 38 New
sePlan ( icescrum2.dao.model.IUser, int[], int[],
icescrum2.service.impl.ReleaseServiceImpl.saveRelease 59 84 30 New
( icescrum2.dao.model.IRelease,
icescrum2.dao.model.IProduct, boolean,
icescrum2.dao.model.IUser)
icescrum2.service.impl.SprintServiceImpl.closeSprint ( 70 120 21 New
icescrum2.dao.model.IRelease,
icescrum2.dao.model.ISprint,
icescrum2.dao.model.IUser,
icescrum2.service.impl.SprintServiceImpl.saveSprint ( 43 69 20 New
icescrum2.dao.model.IRelease, java.lang.Integer,
icescrum2.dao.model.impl.Sprint.equals ( 47 70 84
java.lang.Object)
icescrum2.service.impl.ClicheServiceImpl.createCliche ( 208 343 42
icescrum2.dao.model.IProduct, java.util.Date)
icescrum2.service.impl.ImportXMLServiceImpl.parsePro 73 169 41
duct ( org.w3c.dom.Element)
icescrum2.dao.model.impl.ProductBacklogItem.equals ( 45 40 37
java.lang.Object)
icescrum2.dao.model.impl.Build.equals ( 29 27 24
java.lang.Object)
icescrum2.dao.model.impl.CustomRole.equals ( 27 27 24
java.lang.Object)
icescrum2.service.impl.UserServiceImpl.saveUser ( 24 36 23
icescrum2.dao.model.impl.ExecTest.equals ( 27 25 22
java.lang.Object)
icescrum2.dao.model.impl.Task.equals ( 27 26 22
java.lang.Object)
icescrum2.dao.model.impl.Test.equals ( 27 25 22
java.lang.Object)

5.3.4 Mapping methods by their complexity and efferent coupling
This rule is intended to identify methods whose code has many dependencies to other classes. The concept
of “efferent coupling” refers to those outgoing dependencies.

The principle is that a method with a strong efferent coupling is difficult to understand, maintain and test.
First because it requires knowledge of the different types it depends on, then because the risk of
destabilization is higher because of these dependencies.



This rule is crossed with the cyclomatic complexity to ignore some trivial methods, such as initialization
methods of graphical interfaces that make calls to many classes of widgets without presenting any real
complexity.

This rule considers that a method is non-compliant if it exceeds a threshold of efferent coupling and
threshold of cyclomatic complexity.

The chart below shows a mapping of methods according to their complexity and their efferent coupling. Each
dot represents one or more methods with the same values of complexity and coupling. They are divided into
four zones according to their status in relation to both thresholds:

 The area on the lower left (green dots) contains compliant methods, below both thresholds
 The area on the lower right (gray dots) contains compliant methods; they have reached the
complexity threshold, but remain below the coupling threshold
 The area in the upper left (gray dots) contains compliant methods; they have reached the coupling
threshold, but remain below the complexity threshold
 The area in the upper right (red dots) contains non-compliant methods; above both thresholds


The intensity of the color of the dots depends on the number of methods that share the
same values in complexity and coupling: the more the color of the point is marked, the more
involved methods.



The histogram below provides an additional view of this mapping and precise figures for the four zones in
terms of percentage of methods and statements of the application. The last bars indicate the area of non-
compliance:


The following table details the main non-compliant methods:

Method Efferent Complexity New
Coupling violation
icescrum2.service.impl.ExportPDFServiceImpl.addReleasePlan ( 35 38 New
icescrum2.dao.model.IUser, int[], int[],
icescrum2.service.impl.SprintServiceImpl.closeSprint ( 29 21
icescrum2.dao.model.IRelease, icescrum2.dao.model.ISprint,
icescrum2.dao.model.IUser, icescrum2.dao.model.IProduct)
icescrum2.service.impl.ImportXMLServiceImpl.parseProduct ( 23 41
org.w3c.dom.Element)
icescrum2.service.impl.SprintServiceImpl.autoSaveSprint ( 21 16
icescrum2.dao.model.IRelease, icescrum2.dao.model.IUser,
icescrum2.service.impl.SprintServiceImpl.saveSprint ( 20 20
icescrum2.dao.model.ISprint, icescrum2.dao.model.IRelease,
java.lang.Integer, icescrum2.dao.model.IUser,
icescrum2.service.impl.ImportXMLServiceImpl.importProduct ( 20 18 New
java.io.InputStream, icescrum2.dao.model.IUser,
icescrum2.service.beans.ProgressObject)



5.4 Test
The Test domain provides rules to ensure that the application is sufficiently tested, quantitatively but also
qualitatively, i.e. tests should target risk areas.

5.4.1 Issues
It is important to situate the problems inherent in managing tests to understand the results of analysis for
this area.

5.4.1.1 Unit testing and code coverage
The results of this domain depend on the testing process applied to the project: if automated unit testing
process and / or code coverage are implemented on the project, then the analysis uses the results of these
processes.

As a reminder, we must distinguish unit testing and code coverage:

 A unit test is an automated test, which usually focus on a simple method inside source code. But
since this method has generally dependencies on other methods or classes, a unit test can test a
more or less important part of the application (the larger is this part, the less relevant is the test)

 Code coverage measures the amount of code executed from tests, by identifying each element
actually executed at runtime (statements, conditional branches, methods ...). These tests can be
unit tests (automated) or integration tests / functional (manual or automated).

Code coverage is interesting to combine with the unit tests because it is the only way to measure the code
actually tested. However, many projects still do not check the code coverage, which does not allow verifying
the quality of testing in this type of analysis.

The indicators presented next address both cases; they are useful for projects with unit tests and/or code
coverage but also for other projects.

5.4.1.2 Relevance of code coverage
Code coverage provides figures indicating the proportion of code executed after the tests, for example 68%
of statements of a method are covered or 57% of the project statements...

The problem is that these figures do not take into account the relevance to test the code. For example a
coverage of 70% of the application is a good figure, but the covered code could be trivial and without any
real interest for the tests (e.g. accessors or generated code), whereas the critical code may be located in the
remaining 30%.

The analysis performed here captures the relevance to test of each method, which is used to calibrate the
code coverage requirements and to set appropriate thresholds to better target testing effort towards risk
areas.



5.4.2 TestRelevancyIndex metrics (TRI) and TestEffortIndex (TEI)
To refine the analysis of tests, two new metrics were designed by the Centre of Excellence in Information and
Communication Technologies (CETIC) based on researches conducted during the past 20 years and from the
“Quality Cockpit” knowledge base6.

The TestRelevancyIndex (TRI) measures the relevancy of testing a method in accordance with its technical
risks and its business risk.

Technical risk assesses the probability of finding a defect; it is based on different metrics such as cyclomatic
complexity, number of variables, number of parameters, efferent coupling, cumulative number of non-
compliances...

The business risk associates a risk factor to business features which should be tested in priority (higher risk),
or instead which should not be tested (minor risk). It must be determined at the initialization of the audit to
be considered in the TRI calculations. The objective is to guide the testing effort on the important features.

For this, the TRI is used to classify the methods according to a scale of testing priority, and thus to distinguish
the truly relevant methods to test from trivial and irrelevant methods in this area. For each level of the scale,
a specific threshold to achieve with code coverage can be set. This allows setting a high threshold for critical
methods, and a low threshold for low-priority methods.

The TestEffortIndex (TEI) completes the TRI by measuring the level of effort required to test a method. Like
the TRI, it is based on a set of unit metrics characterizing a method. It helps to refine the decisions to select
the code to be tested by balancing the effort over the relevance test.

The details of calculating these two indexes are providing in annex (8.2 The coupling).

5.4.3 Mapping methods by testing priority
The histogram below shows a mapping of methods according to their priority of testing, using a scale of four
levels based on TRI of methods (each level corresponding to a range of TRI).

This mapping uses the code coverage information only if they were supplied for analysis. For each priority
level are indicated:

 The average coverage rate (0 if coverage information was not provided)
 The number of methods not covered (no coverage)
 The number of methods insufficiently covered (coverage rate below the target rate set for this level
of priority)
 The number of methods sufficiently covered (coverage greater than or equal to the target rate set
for this level of priority)

6
CETIC, Kalistick. Statistically Calibrated Indexes for Unit Test Relevancy and Unit Test Writing Effort, 2010



The table below shows these figures for each priority level, also adding a fifth level corresponding to the
methods without test priority:

Test priority Covered Uncovered Insufficient covered
Critical 0 3 2
High 4 13 5
Medium 6 46 2
Low 18 96 3
None 115 3093 0
[Total] 143 3251 12

5.4.4 Coverage of application by tests
This graph, called “TreeMap” shows code coverage of the application against test objectives. It helps to
identify parts of the application that are not sufficiently tested regarding identified risks. It gathers the
classes of project into technical subsets, and characterizes them following two dimensions:

 size, which depends on the number of statements
 color, which represents the deviation from the test objective set for the classes: the color red
indicates that the current coverage is far from the goal, whereas the green color indicates that the
goal is reached




A class can be green even if it is not or little tested: for example, classes with a low
probability of technical defects or without business risk. Conversely, a class already tested can be
stated as insufficient (red / brown) if its objective is very demanding.

An effective strategy to improve its coverage is to focus on large classes close to the goal.

5.4.5 Most important classes to test (Top Risks)
The following chart allows quickly identifying the most relevant classes to test, the “Top Risks”. It is a
representation known as "cloud" that displays the classes using two dimensions:

 The size of the class name depends on its relevancy in being tested (TRI cumulated for all methods of
this class)
 The color represents the deviation from the coverage goal set for the class, just as in the previous
TreeMap




This representation identifies the critical elements, but if you want to take into account the
effort of writing tests, you must focus on the following representation to select items to be
corrected.

5.4.6 Most important classes to test and require the least effort (Quick Wins)
The “Quick Wins” complements “Top Risks” by taking into account the testing effort required for testing the
class (TEI):

 The size of the class name depends on its interest in being tested (TRI), but weighted by the effort
required (TEI accumulated for all methods): a class with a high TRI and a high TEI (therefore difficult
to test) appears smaller than a class with an average TRI but a low TEI
 The color represents the deviation from the coverage goal set for the class, just like the TreeMap or
QuickWin


5.4.7 Methods to test in priority



The following table details the main methods to be tested first. Each method is associated with its current
coverage rate, the raw value of its TRI and its level of TEI:



Method Coverage Relevancy Priority Effort New
(TRI) violation
icescrum2.service.impl.ExportPDFServiceImpl. 0% 39.0 Critical Very high New
addReleasePlan ( icescrum2.dao.model.IUser,
int[], int[], icescrum2.dao.model.IProduct)
icescrum2.service.impl.ImportXMLServiceImpl. 0% 39.0 Critical Very high
parseProduct ( org.w3c.dom.Element)
icescrum2.service.impl.ClicheServiceImpl.creat 0% 37.0 Critical Very high
eCliche ( icescrum2.dao.model.IProduct,
java.util.Date)
icescrum2.service.impl.ProductBacklogServiceI 76% 36.0 Critical High
mpl.saveProductBacklogitem (
icescrum2.dao.model.IStory,
icescrum2.dao.model.IProduct,
icescrum2.dao.model.ICustomRole)
icescrum2.service.impl.TaskServiceImpl.updat 51% 35.0 Critical High
eTask ( icescrum2.dao.model.ITask,
java.lang.String)
icescrum2.service.impl.ProductBacklogServiceI 60% 34.0 High High
mpl.associateItem (
icescrum2.dao.model.impl.Sprint.equals ( 0% 33.0 High Very high
java.lang.Object)
icescrum2.service.impl.ExportPDFServiceImpl. 0% 33.0 High High New
addProject ( java.util.HashMap,
icescrum2.service.chart.VelocityChartSprint.ini 0% 33.0 High High
t()
icescrum2.service.chart.BurndownChartReleas 0% 33.0 High High
e.init ( )
icescrum2.service.impl.ReleaseServiceImpl.up 45% 32.0 High High
dateRelease ( icescrum2.dao.model.IRelease,
icescrum2.service.impl.TestServiceImpl.saveTe 79% 32.0 High High
st ( icescrum2.dao.model.ITest,
icescrum2.service.impl.SprintServiceImpl.auto 0% 32.0 High Very high
SaveSprint ( icescrum2.dao.model.IRelease,



icescrum2.service.impl.SprintServiceImpl.calcu 47% 32.0 High High
lateDailyHours ( icescrum2.dao.model.ISprint,
int)
icescrum2.service.impl.SprintServiceImpl.close 61% 32.0 High Very high
Sprint ( icescrum2.dao.model.IRelease,
icescrum2.dao.model.impl.ProductBacklogIte 0% 31.0 High High
m.equals ( java.lang.Object)
mpl.changeRank (
mpl.getStory ( org.w3c.dom.Element,
java.util.Map)
mpl.updateProductBacklogItem (
icescrum2.dao.model.ICustomRole)

5.5 Architecture
The Architecture domain aims to monitor compliance of a software architecture model. The target
architecture model has been presented in Chapter 4.3.2 Technical model. The following diagram shows the
results of architecture analysis by comparing this target model with current application code.

Currently, architecture non-compliances are not taken into account in the calculation of
non-compliance of the application.




Non-compliances related to communication constraints between two elements are
represented using arrows. The starting point is the calling element, the destination is the one
called. The orange arrows involve direct communication between a top layer and bottom layer
non-adjacent (sometimes acceptable). The black arrows refer to communications totally
prohibited.

5.6 Duplication
The Duplication domain is related to the “copy-and-paste” identified in the application. To avoid many false
positives in this area, a threshold is defined to ignore blocks with few statements.

Duplications should be avoided for several reasons: maintenance and changeability issues, testing costs, lack
of reliability...

5.6.1 Mapping of duplication
The chart below shows a mapping of duplications within the application. It does not take into account the
duplication involving a number of statements below the threshold, because they are numerous and mostly
irrelevant (e.g. duplication of accessors between different classes sharing similar properties).



Duplicates are categorized by ranges of duplicated statements. For each range is presented:

 The number of different duplicated blocks (each duplicated at least once)
 The maximum number of duplications of the same block


5.6.2 Duplications to fix in priority
The following table lists the main duplicates to fix in priority. Each block is identified by a unique identifier,
and each duplication is located in the source code. If a previous audit were completed, a flag indicates
whether duplication is new or not.



Duplication Duplicated Class involved Lines New
number blocks size violation
239 111 icescrum2.presentation.app.roadmap.RoadmapUI 858:1003 New
239 111 icescrum2.presentation.app.releasebrowser.ReleaseBr 1045:1190 New
owserUI
owserUI
237 56 icescrum2.service.impl.ClicheServiceImpl 309:373
237 56 icescrum2.service.impl.ClicheServiceImpl 201:263
236 52 icescrum2.service.chart.GlobalChartTest 243:316
236 52 icescrum2.service.chart.VelocityChartSprint 219:292
236 52 icescrum2.service.chart.ExecChartTest 156:229
235 50 icescrum2.service.chart.BurndownChartProduct 322:391
owserUI
233 48 icescrum2.service.chart.BurndownChartRelease 202:268

5.7 Documentation
The Documentation domain aims to control the level of technical documentation of the code. Only the
definition of standard comment header of the methods is verified: Javadoc for Java, XmlDoc for C#. Inline
comments (in the method bodies) are not evaluated because of the difficulty to verify their relevance (often
commented code or generated comments).

In addition, the header documentation is verified only for methods considered quite long and complex.
Because the effort to document trivial methods is rarely justified. For this, a threshold on the cyclomatic
complexity and a threshold on the number of statements are defined to filter out methods to check.

5.7.1 Mapping documentation issues
The chart below shows the status of header documentations for all methods with a complexity greater than
the threshold. The methods are grouped by ranges of size (number of statements). For each range are given
the number of methods with header documentation and the number of methods without header
documentation. The red area in the last range corresponds to the methods not documented therefore non-
compliant.



5.7.2 Methods to document in priority
The following table lists the main methods to document in priority:

Method Instructions Complexity New
violation
icescrum2.service.impl.ExportXMLServiceImpl.exportSprint 81 10 New
icescrum2.service.impl.ReleaseServiceImpl.saveRelease 59 30 New
icescrum2.service.impl.ClicheServiceImpl.createCliche 208 42
icescrum2.service.impl.SprintServiceImpl.autoSaveSprint 89 16
icescrum2.service.chart.VelocityChartSprint.init 78 13
icescrum2.service.impl.SprintServiceImpl.closeSprint 70 21
icescrum2.service.impl.ExportXMLServiceImpl.exportItem 66 10
icescrum2.service.chart.BurndownChartRelease.init 66 14



6 Action Plan
For each domain, a recommendation of corrections was established on the basis of tables detailing the rules
and code elements to correct. The following graph provides a comprehensive strategy to establish a plan of
corrections by defining a list of actions. This list is prioritized according to the expected return on
investment: the actions recommended in the first place are those with the best ratio between effort to
produce and gain on the overall rate of non-compliance.

Here is the explanation of each step:

1. Correction of forbidden practices
These practices are often easy to correct, and because they invalidate the classes directly, the
correction generally leads to significantly improve the overall rate of non-compliance (if classes are
not invalidated by other rules).

2. Splitting long methods
Using some IDE, it is often easy to break a method too long into several unit methods. This is
achieved using automated operations performing refactorings, avoiding any risk of regression
associated with manual intervention.

3. Documentation of complex methods
This step aims to document methods identified as non-compliant in documentation domain, this is a
simple but potentially tedious operation.

4. Correction of inadvisable practices
Correspond to all practices remaining after correction of forbidden practices: practices highly
inadvisable, inadvisable and to be avoided.



5. Removing of duplications
This operation is more or less difficult depending on the case: you have first to determine whether
the duplication should really be factorized, because two components may share the same code base
but be independent. Note that the operation can be automated by some IDE and according to the
type of duplication.

6. Modularization of complex operations
This operation is similar to splitting long methods, but is often more difficult to achieve due to the
complexity of the code.

The action plan can be refined on the Quality Cockpit using the mechanism of "tags." Tags
allow labeling the results of analysis to facilitate operations such as the prioritization of
corrections, their assignment to developers or the targeting of their fix version.



7 Glossary

Block coverage
Block coverage measures the rate of code blocks executed during testing compared to total blocks. A code
block is a code path with a single entry point, a single exit point and a set of statements executed in
sequence. It ends when it reaches a conditional statement, a function call, an exception, or a try / catch.

Branch coverage
Branch coverage measures the rate of branches executed during tests by the total number of branches.

if (value)
{
//
}
This code will be covered by branches to 100% if the if condition was tested in the case of true and false.

Line coverage
Lines (or statements) coverage measures the rate of executed lines during testing against the total number
of lines. This measure is insensitive to conditional statements, coverage of lines can reach 100% whereas all
conditions are not executed.

Line of code
A physical line of a source code in a text file. White line or comment line are counted in lines of code.

Non-compliance
A test result that does not satisfy the technical requirements defined for the project. Non-compliance is
related to a quality factor and a quality domain.

Synonym (s): violation

Quality domain
The test results are broken down into four areas depending on the technical origin of the non-compliances:

 Implementation: Issues related to the use of language or algorithmic
 Structure: Issues related to the organization of the source code: methods size, cyclomatic complexity
...
 Test: Related to unit testing and code coverage
 Architecture: Issues related to the software architecture
 Documentation : Issues related to the code documentation: comments headers, inline comments ...
 Duplication : The “copy-pastes” found in the source code

Quality factor
The test results are broken down into six quality factors following application needs in terms of quality:

 Efficiency: Does the application ensure required execution performance?
 Changeability: Do the code changes require higher development costs?



 Reliability: Does the application contain bugs that affect its expected behavior?
 Maintainability: Do the maintenance updates require a constant development cost?
 Security: Has the application security flaws?
 Transferability: Is the transfer of the application towards a new development team a problem?

Statement
A statement is a primary code unit. For simplicity, a statement is delimited by a semicolon (;) or by a left
brace ({). Examples of statements in Java:

 int i = 0;
 if (i == 0) {
 } else {}
 public final class SomeClass
 {
 import com.project.SomeClass;
 package com.project;
Unlike lines of code, statements do not include blank lines and comment lines. In addition, a line can contain
multiple statements.



8 Annex

8.1 Cyclomatic complexity
Cyclomatic complexity is an indicator of the number of possible paths of execution.

Its high value is a sign that the source code will be hard to understand, to test, to validate, to maintain and to
evolve.

8.1.1 Definition
Imagine a control graph that represents the code that you want to measure the complexity. Then, count the
number of faces of the graph. This gives the structural complexity of the code, also called cyclomatic
complexity.


Java source code analysis for better testing

Java source code analysis for better testing

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