Defect prevention techniques

Software Defect Prevention Techniques
- Example Project -

Zarko Acimovic
Copyright © 2012 Zarko Acimovic

All rights reserved.

ISBN-10: 1481113305
ISBN-13: 978-1481113304

DEDICATION

I dedicate this book to my parents, Ivana and Goran

CONTENTS

1 Introduction

2 Theoretical Foundations for Defect Prevention 1

3 Automatic Tools for Defect Prevention 24

4 Tools for Defect Prevention in Java Software Development 25

5 Sample Project Software Requirements 25

6 Source Code with Violations 26

7 Design Defects Detected by ArgoUML 192

8 Examples of Design Defects in Sample Project 196

About the Author

Zarko Acimovic

1 INTRODUCTION

I present 5000 lines of Java source code from prototype project. The code is operational and fulfills its software
requirements. I wrote the code in 2004 and ever since had several business offers to commercialize it, which I resisted
due to complexity of the code. I tested the code with static analysis tools PMD, FindBugs, StateOfFlow and
ArgoUML in order to comprehend its architectural quality. Source code is presented as written in 2004. These tools
uncovered 1123 code violations (almost 1 violation per 5 lines of code) and 121 software design violations. All these
violations are presented in book with references to the source code. I recommend to readers to use these tools during
development and correct all the violations reported.

2 THEORETICAL FOUNDATIONS FOR DEFECT PREVENTION

Below are the details of E-learning course “Software Engineering” from IIT Bombay India >> NPTEL >> Courses
>> Computer Science and Engineering >> Software Engineering (Video).
My opinion is that this course provides solid theoretical foundation for applying software defect prevention
techniques. The course can be found on following location

http://nptel.iitm.ac.in/video.php?subjectId=106101061

Here are the details of the course:

1 - Introduction to Software Engineering (52:21)
2 - Introduction to Software Engineering (52:55)
3 - Overview of Phases (57:22)
4 - Overview of Phases (57:03)
5 - Requirements Engineering / Specification (56:39)
6 - Formal Specification (51:44)
7 - Algebraic Specification Methods (57:34)
8 - Systems Modeling Overview (59:38)
9 - Process Modeling - DFD , Function Decomp (56:28)
10 - Process Modeling - DFD, Function Decomp (53:23)
11 - Data Modeling - ER Diagrams, Mapping (1:00:55)
12 - Data Modeling - ER Diagrams, Mapping (58:08)
13 - Production Quality Software - Introduction (53:04)
14 - Software Design - Primary Consideration (1:04:43)
15 - Design Patterns (56:13)
16 - Class and Component Level Design (54:34)
17 - Architectural Design (59:28)
18 - Software Testing - I (55:39)
19 - Software Testing - II (51:18)
20 - Structural Programming and Some implementation (45:05)
21 - Software Metrics and Quality (54:51)
22 - Verification and Validation (52:43)

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Software Defects Prevention Techniques – Example Project

23 - Case Study (54:55)
24 - Case Study (58:39)
25 - Software Evolution (55:41)
26 - Agile Development (55:33)
27 - Software Reuse (53:43)
28 - Reuse Continued (57:07)
29 - Introduction to Project Management (52:36)
30 - Project Scope Management (1:08:45)
31 - Project Time Management (56:51)
32 - Estimation - I (51:42)
33 - Estimation - II (50:38)
34 - Project Quality Management (58:32)
35 - Quality Management Systems - I (54:43)
36 - Quality Management Systems (54:53)
37 - Project Configuration Management (53:00)
38 - Project Risk Management (56:04)
39 - Other PM Processes (55:41)

Here are the details of the videos:

1. Introduction to Software Engineering (52:21)

2. Introduction to Software Engineering (52:55)

• Waterfall Model for Development
• Deliverables in Waterfall Model
• Cost/Effort Distribution
• Shortcomings of Waterfall Model
• Prototyping Model
• Prototyping
• Limitations of Prototyping
• Iterative Development
• Spiral Model
• Project Management Process
• Project Planning
• Project Monitoring and Control

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3. Overview of Phases in Software Development (57:22)

4. Overview of Phases in Software Development (57:03)

• Structured Analysis
• Structured Methodology
• Requirement Specification Format
• System Design
• Alternatives
• Design goals
• System Architecture
• Structure Chart
• Structure Chart Notation
• OO Approach
• Design Document Format
• Detailed Design
• Implementation Phase
• Operations & Maintenance
• Summary

5. Requirements Engineering / Specification (56:39)

• Objectives
• Requirements engineering
• What is a requirement?
• Requirements abstraction (Davis)
• Types of requirement
• Requirements Audience
• Functional and non-functional requirements
• Functional requirements
• The LIBSYS system
• Examples of functional requirements
• Requirements imprecision
• Requirements completeness and consistency
• Non-functional requirements
• Non-functional classifications
• Non-functional requirement types
• Non-functional requirements examples
• Goals and requirements
• Examples
• User requirements
• Problems with natural language
• LIBSYS requirement
• Editor grid requirement

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• Requirement problems
• Structured presentation
• Guidelines for writing requirements
• System requirements
• Requirements and design
• Alternatives to NL specification
• Structured language specifications
• Form-based specifications
• Tabular specification
• Graphical models
• PDL interface description
• The requirements document
• IEEE requirements standard

6. Formal Specification (51:44)

• Natural Language Requirement Specification
• Problem Statement
• The Need for Formal Specification
• Formal methods
• Acceptance of formal methods
• Use of formal methods
• Specification in the software process
• Specification techniques
• Formal specification languages
• Use formal specification
• Development costs with formal specification
• Properties of Formal Specifications
• Library Example-Informal Statement
• Library Example -- Formalization
• Library Example -- Formalization - 2
• Library Example -- Prove Correctness
• Specification Types
• Interface specification
• Sub-system interfaces
• Behavioral specification
• Key points

7. Algebraic Specification Methods (57:34)

• Disadvantages of NL specifications
• Another Perspective - Dangers of Physical Representations in Analysis
• Towards Abstraction
• What does a Abstract Data Type (ADT) consist of?7:29
• What about Post Conditions?

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• Algebraic Manipulation using Axioms
• Abstract Math to Concrete realizations
• ADTs and Information Hiding
• Completeness of Specification
• Definition: sufficient completeness
• ADT Consistency

8. Systems Modeling Overview (59:38)

• Model types
• Context models
• The context of an ATM system
• Process models
• Behavioral models
• Order processing DFD
• Microwave oven model
• Microwave oven state description
• Microwave oven stimuli
• Microwave oven state description
• Microwave oven stimuli
• Microwave oven operation
• Semantic data models
• Library semantic model
• Data Dictionary Entries
• Object models
• Inheritance models
• Multiple inheritance
• Object aggregation
• Object behavior modeling
• Structured methods

9. Process Modeling - DFD , Function Decomposition (56:28)

• ER MODEL
• ENTITY
• ENTITY SET
• ATTRIBUTE
• DOMAIN
• PRIMARY KEYS
• EXAMPLE : A COLLEGE
• RELATIONSHIP
• RELATIONSHIP SET
• DEPICTING A RELATIONSHIP
• PRIMARY KEY FOR REPATIONSHIPS
• RELATIONSHIP CARDINALITY

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10. Process Modeling - DFD, Function Decomposition (53:23)

• RELATIONSHIP CARDINALITY
• EXISTENCE DEPENDENCE
• TERNARY RELATIONSHIPS
• WEAK ENTITY
• EXTENDED E-R MODEL
• Generalization

11. Data Modeling - ER Diagrams, Mapping (1:00:55)

• Generalization
• Specialization
• Inheritance
• Aggregation
• Process Model
• Function Decomposition
• FD Diagrams: Examples

12. Data Modeling - ER Diagrams, Mapping (58:08)

• Data Flow Diagram (DFD)
• DFD Notation
• Context Diagram
• Process Refinement
• Physical DFD
• Showing Boundaries
• DFD Example 1: Payroll
• DFD Example 2: Old Car Mart
• DFD Example Old Car Mart
• Example 3: Book Supplier
• Book Supplier: Exploding Process 2
• Book Supplier : homework

13. Production Quality Software - Introduction (53:04)

• Software construction then and now
• Software Crisis (Late 1980s)
• More perspective on the Software Crisis
• Brian Russell's Laws of Software Relativity
• Properties of Failing software
• Common Error in Managing the Process

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• Software Maintenance
• Quality Factors for Software
• Quality Factors
• Quality Factors - contd.
• Quality Factors
• Keys to achieving Structural Quality
• What ls Abstraction?
• Abstraction
• Abstraction Techniques
• Encapsulation
• Modules
• Desirable Characteristics - Weak Coupling
• Information Hiding
• Protocol Vs Behavior
• IH and Abstraction
• Factorization and Specialization
• Inclusion
• Benefits of Inheritance
• Uses for inheritance

14. Software Design - Primary Consideration (1:04:43)

• What's Design?
• Example Designs in Real Life
• Programs
• Example Designs in Real Life
• Design in Software Engineering
• Examples of Process Design
• What is covered in Product Design?
• From Analysis to Design
• Factors To be considered in Design
• Factors to be considered in Design
• Process of Complex System Design
• Top-down Vs. Bottom-up Approach
• Decomposition
• Composition/Interconnection
• Basic Principles To be applied during design
• Abstraction
• Example Abstractions
• Describing Abstractions
• Encapsulation
• Refinement
• Refinement and Change Process
• Communication
• Other Kinds of Communication

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15. Design Patterns (56:13)

• Reuse in Software Engineering
• Patterns in Software Engineering
• Design Patterns
• Describing a Design Pattern
• Pattern Description Template provided by
• Classification of Patterns
• Examples of Creational Patterns
• Behavioral Patterns
• A Problem
• The Solution
• The Design Pattern: Prototype
• Singleton Pattern
• Implementing Singleton
• Adapter Pattern
• Composite Pattern
• The Solution
• Instance Structure for an Instance of a Composite Class
• The Composite Pattern
• The Facade Pattern
• How to interact with components with a subsystem?
• The Facade Pattern
• Proxy Pattern: A Mechanic for Communication
• Real object and Proxy object are different
• The Proxy Pattern
• The Decorator Pattern: Object Diagram
• Visual Component
• The Template Method Pattern
• Strategy Pattern

16. Class and Component Level Design (54:34)

• Class
• Example Classes
• Kinds of Classes
• Levels of Abstraction
• Beck and Cunningham's CRC Method
• CRC: our recommendation
• A system decomposed in CRCs
• Contributions of CRC
• Bertrand Meyer' Design-by-Contract
• Design by Contact Method
• Contracts
• An Example Contact for class Book

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• A Contact Specification
• Class Design
• Part-Whole Design
• Odell's Classification Criteria
• Component-Integral Object
• Material-Object (made of)
• Portion-Object
• Place-Area
• Member-Bunch
• Member-Partnership
• Non-aggregation relations
• Transitivity in Part-Whole
• Two Kinds of Part-whole Relations in UML
• Designing New Subclasses From Old: Inheritance
• Use of Inheritance in a Subclass
• Components
• Use of Inheritance in a Subclass
• Components
• Design of Components
• Decisions about component's non-functional properties
• Reuse in Component Technologies

17. Architectural Design (59:28)

• Software Architecture
• Why Do We need Architecture?
• Basic Principles applied by Architects
• Several Approaches to Architecture
• The Zachman Framework
• Open Distributed Processing Reference Model (ODP-RM)
• ODP: Enterprise viewpoint
• ODP: Information viewpoint
• ODP: Computational viewpoint
• ODP: Computation viewpoint
• ODP: Engineering viewpoint
• ODP: Transparencies
• ODP: Transparencies Defined
• 4+1 View Model
• Unified Process Model of Architecture
• Commonly occurring Architectural Patterns
• Layers
• Peers
• Client-server
• Pipelines
• Transactional Flows

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• Filters
• Blankboards
• Facade
• Broker
• MVC
• Microkernel
• Framework Architectures
• A Framework
• References/Readings

18. Software Testing - I (55:39)

• Why Testing?
• A Test Case
• What criteria to use?
• Black Box Testing
• White Box Testing
• Levels of Testing
• Stub Modules
• Test Drivers
• Test Drivers during Partial Integration
• Testing Modules with Top Down Integration
• Testing Modules with Bottom Up Integration
• Regression Testing
• Monitoring Behavior of Programs
• Documentation Probes
• Standard Error Probes and Exceptions (user defined)
• Assertions for defensive programming
• Different Types of Assertions
• IS the output of a test correct?
• Test Objectives
• Alpha testing and Beta testing
• Debugging
• Testing In Software Development

19. Software Testing - II (51:18)

• Black box vs. white box testing
• Black Box Testing (External)
• White Box Testing (Internal)
• Statement Coverage
• An Example for Statement Coverage
• Observations

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• An Example for Statement Coverage
• Observations
• Implicit statements
• Basic Path Testing
• A Sequential Composition
• A Branching Statement
• A While Statement
• A Repeat Statement
• A Switch Case Statement
• A Compound Condition
• Cyclomatic Complexity
• Cyclomatic Complexity Example
• Condition Testing
• Condition Testing Strategies
• Data Flow Testing Strategies
• Exercise: Try different strategies on the below program

20. Structural Programming and Some implementation (45:05)

21. Software Metrics and Quality (54:51)

• Why Measurement?
• Use of Software Measurement
• The attributes that can be captured
• Which one is a good measure?
• What to measure in software?
• Measurement Scales
• Ordinal Scale
• Interval Scale
• Ratio Scale
• Absolute Scale
• Size Metrics
• Length
• Functionality
• Complexity
• Measuring Structure
• Coupling and cohesion
• Object Oriented Metrics: CK and MOOD
• Quality Guidelines for Coding and Development
• Defensive Programming for Modules, Functions, Procedures, Classes
• Preconditions
• Invariants

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• Use of Software Measurement
• Separate Compilation
• Makefile
• Separate Compilation
• Makefile
• A Sample Makefile
• Code organization
• Development
• Some good practices

22. Verification and Validation (52:43)

• Verification vs validation
• The V & V process
• V & V goals
• V & V confidence
• Static and dynamic verification
• Program testing
• Types of testing
• Testing and debugging
• The debugging process
• V & V planning
• V-model of development
• The Structure of a software test plan
• Software inspections
• Inspection success
• Inspections testing
• Program inspections
• Inspection pre-conditions
• Inspection procedure
• Inspection Roles
• Inspection Checklists (2)
• Inspection Checklists (3)
• Inspection rate
• Automated static analysis
• Static Analysis Checks
• Stages of static analysis
• LINT static analysis
• Verification and formal methods
• Arguments for formal methods

23. Case Study (54:55)

• Case study: library book circulation system
• BOOK CIRCULATION

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• STATEMENT OF PROJECT SCOPE AND OBJECTIVES
• THE FEASIBILITY STUDY: CIRCULATION
• Financial analysis for alternatives 1 :
• Alternatives 2
• Plan for alternatives 1
• Feasibility ...
• Requirements Analysis
• Circulation System
• Draw first level DFD
• Requirements Analysis

24. Case Study (58:39)

• Requirements Analysis...
• Refinement of issue process
• Requirements Analysis...
• Requirements Specification...
• SRS ...
• System Design: CIRCULATION
• System Design ...
• System Design
• E-R DIAGRAM
• Table Design
• Physical DB Design
• Physical DB Design...
• Physical DB Design...
• Software Architecture
• Software Architecture...
• Implementation Schedule
• Implementation Schedule...
• Design documentation
• Detailed Design
• Data and Module Specification
• Module ...
• Implementation

25. Software Evolution (55:41)

• Software Change
• Software change control
• Software change strategies
• Program evolution dynamics

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• Laws of Program Evolution
• Applicability of Lehman's laws
• Software maintenance
• Maintenance is inevitable
• Causes of maintenance
• Distribution of maintenance effort
• Types of Maintenance
• Breakup of costs
• Spiral maintenance model
• Maintenance costs
• Maintenance costs factors
• Problems facing Maintainers
• Approaches to Maintenance
• The Change process
• Change requests
• Change implementation
• Maintenance prediction
• Change prediction
• Complexity metrics
• Process metrics

26. Agile Development (55:33)

• Objectives
• Requirements
• Characteristics of Agile Processes
• An iterative development process
• Advantages of incremental development
• Problems with incremental development
• Prototyping
• Software prototyping
• Benefits of prototyping
• Throw -away prototypes
• Incremental Development & Prototyping
• Conflicting objectives
• Agile methods
• Principles of Agile Methods
• Problems with agile methods
• Extreme programming
• The Four Core Values of XP
• Communication
• Feedback
• Courage
• The XP release cycle
• XP Practices
• XP Practices - 2

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• XP and agile principles
• Requirements scenarios
• Story Card for document downloading
• XP Design Guidelines
• XP and change
• Testing in XP
• Task cards for document downloading
• Test Case Description
• Test- first development
• Pair programming
• XP Summary

27. Software Reuse (53:43)

• Design with Reuse
• Objectives
• Software reuse
• Benefits of reuse
• Requirements for design with reuse
• Reuse problems
• Generator-based reuse
• Types of program generator
• Reuse through program generation
• Component-based development
• Components
• Component abstractions
• CBSE processes
• An opportunistic reuse process
• Development with reuse
• CBSE problems
• Application frameworks
• Framework classes
• Extending frameworks

28. Reuse Continued (57:07)

• Application frameworks
• Framework classes
• Extending frameworks
• Evaluating Frameworks
• Framework evaluation criteria

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• Evaluating Frameworks
• COTS product reuse
• Integration Approaches
• Examples of COTS muse
• COTS system integration problems
• Component development for reuse
• Reusable components
• Re-usability enhancement
• Generalization Techniques
• Generating good mental Models
• Application families
• Application family specialization
• Inventory management systems
• Application family architectures
• A library system
• Library system
• Family member development
• Design patterns
• The Observer pattern

29. Introduction to Project Management (52:36)

• What is Project Management ?
• Who Executes a Project?
• An Effective PM Needs to Do the Following:
• Productivity Gains With Standards and Procedures
• Software Process is a Part of Organizational Process
• Software Project Phases and Activities
• Software Development Strategies at a Glance
• Project Management Process Groups: Schematic
• Illustration: Interaction Within and Across Project
• Software Development Methodology: Schematic
• PMBOK (2000)
• Framework for Project Management
• PMI Developed Code Of Ethics (1/2)
• Impact of Good Project Management
• Software Project Management
• Suggested Readings

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30. Project Scope Management (1:08:45)

• Scope Management Subprocesses
• Illustrative Comparison of Projects
• Another Way of Comparing Projects:
• PM Must Question ALL Aspects of a Project
• Illustration: Stakeholder Analysis
• Illustration: Objectives of a Hospital IS
• Illustration: Project Charter (1/3)
• Illustration: WBS Organized by phases
• Summary: Scope management Subprocesses

31. Project Time Management (56:51)

• Project Time Management Subprocesses
• WBS to Precedence Relationship
• Precedence Diagramming Method (PDM): Types of Dependencies
• Illustration: PDM Network
• Illustration: Arrow Diagramming Method (ADM) Network
• Precedence Relationship to Schedule
• Schedule Development Preferences
• Illustration of a Schedule
• Software Support for Project Management
• Summary: Time Management Process

32. Estimation - I (51:42)

• Estimation is an Ongoing Activity
• Stages in Project Estimation
• Estimation Approaches
• PERT Sizing Approach to Estimation
• Estimation: Levels of Application
• Function Point Counting Procedure
• Components of FP Count
• FP for Average Complexity Functions

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33. Estimation - II (50:38)

• Marketing MIS: data flow diagram
• General Systems Characteristics (GSCs)
• Value Adjustment Factor (VAF)
• GSC and FPC: Marketing MIS
• Marketing MIS: Cost and Price
• COnstructive COst MOdel (COCOMO): Intd.
• Marketing MIS Modules
• Marketing MIS: Pert sizing
• COCOMO Equations
• COCOMO Cost Drivers (1/2)
• COCOMO Cost Drivers (2/2)
• Cost Driver Effort Multipliers
• Effort Multipliers: Marketing MIS
• Marketing MIS: COCOMO Calculations
• Effort and Schedule Distribution by Phase (%)
• Marketing MIS: Phase Effort and Schedule
• Network Precedence: Marketing MIS
• Effort Distribution by Activity: Marketing MIS
• Critical Path marketing MIS
• Gantt Chart/Histogram:Marketing MIS

34. Project Quality Management (58:32)

• Definitions of Quality (1/2)
• Definitions of Quality (2/2)
• Quality Management Gurus
• Modern Quality Management Emphasizes on:
• Project Quality Management Subprocess
• Quality Policy
• Strategic Planning for Quality
• Quality Characteristics: Illustration
• Boehm's Description of Quality
• Quality Measurements are Used for:
• Illustration: Template for Usability
• Quality Benchmarking
• Cost of Quality
• Quality Planning Process: Outputs
• What is Quality Assurance?
• Main Goals of Quality Assurance:
• Role of QA During Development (1/2)
• VV&T Activities in SW Project (1/3)
• Opportunity for Improvement (OFI)

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• Who Identifies OFI?
• Improvement in Practice and Documentation
• Quality Control Process
• QC is Performed...
• Pareto Chart: Illustration
• Control Chart: Schematic

35. Quality Management Systems - I (54:43)

36. Quality Management Systems (54:53)

• Who is a Process?
• Process Capability and Maturity
• Concept of Maturity Level
• Capability Maturity Models (CMM)
• Some of the Existing CMMs
• Capability Maturity Model Integrated (CMMI)
• CMMI ls Tailorable
• Staged Model: Maturity Levels
• Maturity level Structure
• Structure of Staged Representation
• PA Level 2
• PA Level 3
• PA Level 4
• PA Level 5
• Process Visibility with levels
• Process Capability with Levels
• Continuous Representation
• Structure of Continuous Representation
• PAs in Staged Representation
• Capability and Maturity levels
• Progression in Staged model
• Progression in Continuous model
• When to chose continuous Representation?
• implementation Road Map

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37. Project Configuration Management (53:00)

• Change Control System: Schematic
• What is Configuration Management(CM)?
• CM Functions
• Typical Application Specific Cls
• Versioning of Cls
• Concept of Baseline
• Configuration Control
• Change Control Procedure (1/2)
• Change Control Procedure (2/2)
• Configuration Status Accounting
• Configuration Audit
• Configuration Management Plan

38. Project Risk Management (56:04)

• Project Risk Management Processes
• Risk Management Planning Process
• Risk Manage. Planning Process: Outputs
• Risk identification Process Involves:
• Risk Analysis Processes
• Qualitative Risk Analysis Process
• Illustration: Risk Impact Rating Table
• Impact, Frequency, and Risk Exposure
• Illustration: Quantitative Risk Analysis
• Risk Response Planning Process (2/2)
• Lessening the Risks
• Contingency Actions
• Risk Monitoring and Control Process
• Illustration: Tracking The Top 10 Risks

39. Other PM Processes (55:41)

• Other Project Management Processes
• Project Cost Management Processes
• Illustration: Cost Budget (1/2)
• Illustration: Cost Budget (2/2)
• Human Resource Management Processes
• Impact of Organization Structure on Projects
• Typical Software Project Organization
• Software Development Responsibilities Need to be shared by all stakeholders
• Illustration: Responsibility Assignment Matrix
• Project Communications Management Processes
• Illustration: Stakeholder Communications Analysis

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• Project Reporting and Review: Schematic
• Administrative Closure Process Covers:
• Administrative Closure Process Outputs
• Project Procurement Management Processes
• Project Integration Management Involves:
• Outputs from Project Plan Process: Uses
• Objectives of Overall Change Control Process
• Integrated Change Control Involves:
• Organizational Learning
• Role of PM
• Important Skills for Project Manager
• Engineers vs. Managers

2 AUTOMATIC TOOLS FOR DEFECT PREVENTION

Prototyping (modeling) defect prevention method has efficiency 52%. Before implementing this method defect
potential per 1 FP (function point) was 5, after, 2.4.
Tool: ArgoUML

Static analysis of source code defect prevention method has efficiency 44%. Defect potential per 1 FP was 5, after
implementing this method is 2.8.
Tool: Coverity

Mathematical test case design defect prevention efficiency was 34%. Defect potential per 1 FP is 5, after is 3.3.
Tool: Bullseye

Bonus: Root cause analysis 1044-1993 - IEEE Standard Classification for Software Anomalies. Efficiency 41% -
Before 5 – After 2.95

Source: Chapter 3. Estimating and Measuring Software Quality. The Economics of Software Quality, ISBN:
9780132564762 , Capers Jones, Olivier Bonsignour

http://www.amazon.com/Economics-Software-Quality-Capers-Jones/dp/0132582201
http://www.informit.com/store/product.aspx?isbn=0132582201

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3 TOOLS FOR DEFECT PREVENTION IN JAVA SOFTWARE PROJECTS

Source: http://codedependents.com/2009/07/01/top-5-static-analysis-plugins-for-eclipse/

Code Coverage tool EclEmma http://www.eclemma.org/

Byte Code Analysis FindBugs http://findbugs.sourceforge.net/

Code Complexity Analysis http://www.stateofflow.com/projects/16/eclipsemetrics

Dependency Analysis JDepend4Eclipse http://andrei.gmxhome.de/jdepend4eclipse/

Source Code Analysis PMD http://pmd.sourceforge.net/

4 SAMPLE PROJECT SPECIFICATION

Project duration 3 months, single developer , 5000 lines of code (including comments), 15 Java 2 Micro Edition
classes

Tools used: Sun J2ME Wireless Toolkit, Eclipse, IBM WebSphere Device Developer 5.5, CVS, Motorola and Nokia
phone emulators and SDKs. Technology: J2ME, MIDP 2.0, CLDC 1.1.

Device-independent Java 2 Micro Edition (J2ME) midlet, executable in any emulator or mobile device, for displaying
map with scale, following moving objects, zoom in-out and pan, selection of location , measuring distance, following
individual or vehicle on map with route presentation, presentation of waypoints on map, presentation of list of
existing waypoints (sorted by name, type, distance) for selecting destination or editing and deletion, creating, editing
and deletion of waypoint – points with coordinates, name, type, icon; coordinates are defined by current position,
selected location on map or inserted in textual form, selection of waypoint as destination and navigation towards that
destination. Some classes implemented: MapBackground, MapObject, Point, SelectorPoint, PVector, MapsMIDlet

Project demo web site: https://sites.google.com/site/j2memaps/

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5 PMD, FINDBUGS AND STATEOFFLOW VIOLATIONS IN SOURCE CODE

Here are the violations detected in CommaHyphenString.java Description/ Line/ Type of tool

Description Line Type
All classes and interfaces must belong to a named package 9 PMD Marker
Unused field: CommaHyphenString.lastIndex 12 FindBugs
Use explicit scoping instead of the default package private level 12 PMD Marker
Document empty constructor 13 PMD Marker
Lines of Code in Method is 27 16 Metrics Marker
Number of Statements is 28 16 Metrics Marker
Avoid variables with short names like s 19 PMD Marker
Parameter 's' is not assigned and could be declared final 19 PMD Marker
Local variable 'lastIndex' could be declared final 20 PMD Marker
Avoid variables with short names like ss 22 PMD Marker
A method should have only one exit point, and that should be the last statement in the method 24 PMD Marker
Avoid variables with short names like v 27 PMD Marker
Consider replacing this Vector with the newer java.util.List 27 PMD Marker
Local variable 'v' could be declared final 27 PMD Marker
Use ArrayList instead of Vector 27 PMD Marker
Avoid variables with short names like ss 35 PMD Marker
Avoid variables with short names like s 47 PMD Marker
Avoid using if statements without curly braces 53 PMD Marker
CommaHyphenString.getStringsOnly(String) concatenates strings using + in a loop 54 FindBugs
Prefer StringBuffer over += for concatenating strings 54 PMD Marker

Here is the CommaHyphenString.java source code

1 /**
2 *
3 * CommaHyphenString parses .properties file. It eliminates commas or low
lines
4 * from .properties file so items in it( such as categories) could be
properly
5 * showed on screen
6 */
7 import java.util.*;
8

xxvi


9 public class CommaHyphenString {
10
11 //String s;
12 int lastIndex;
13 CommaHyphenString(){}
14
15
16 /** Eliminates commas, returns array of strings with low line
17 * @return String[]
18 */
19 String[] getWithLowLine(String s) {
20 int lastIndex = defineLast(s);
21 if(lastIndex==0){
22 String[] ss = new String[1];
23 ss[0] = s;
24 return ss;
25 } else {
26 int start = -1;
27 Vector v = new Vector();
28 int current = s.indexOf(',');
29 do {
30 v.addElement(s.substring(start+1,current));
31 start = current;
32 current = s.indexOf(',',current+1);
33 } while (start!=lastIndex);
34
35 String[] ss = new String[v.size()+1];
36 for(int i=0; i<v.size(); i++){
37 ss[i] = (String)v.elementAt(i);
38 }
39 ss[v.size()] = s.substring(lastIndex+1,s.length());
40 return ss;
41 }
42 }
43
44 /** Eliminates low line
46 */
47 String[] getStringsOnly(String s){
48 String[] temp = this.getWithLowLine(s);
49 for (int i=0; i<temp.length; i++){
50 char[] tempChar = temp[i].toCharArray();
51 String k = "";
52 for (int j=0; j<tempChar.length; j++){
53 if(tempChar[j]=='_') tempChar[j]=' ';
54 k+=tempChar[j];
55 }
56 temp[i] = k;
57 }
58 return temp;
59 }

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60
61
62 /** Returns categories with low line
64 */
65 String[] getCategoriesHyphen(String s){
66 return this.getWithLowLine(s);
67 }
68
69 /** Returns categories
71 */
72 String[] getCategories(String s){
73 return this.getStringsOnly(s);
74 }
75
76 /** Defines index of last comma in string
77 * @return integer
78 */
79 public int defineLast(String s){
80 int lastIndex = 0;
81 char c[] = s.toCharArray();
82 for (int i=0; i<c.length; i++){
83 if(c[i]==',') lastIndex=i;
84 }
85 return lastIndex;
86 }
87
88 }

xxviii


CompassCanvas.java violations

Lack of Cohesion in Methods (Henderson-Sellers) is 75% 10 Metrics Marker
Lack of Cohesion in Methods (Total Correlation) is 1,668% 10 Metrics Marker
Number of Fields is 23 10 Metrics Marker
The class 'CompassCanvas' has a Cyclomatic Complexity of 6 (Highest = 17). 10 PMD Marker
To be compliant to J2EE, a webapp should not use any thread. 10 PMD Marker
Too many fields 10 PMD Marker

Found non-transient, non-static member. Please mark as transient or provide accessors. 11 PMD Marker
Avoid variables with short names like c 18 PMD Marker
Unused field: CompassCanvas.c 18 FindBugs
Avoid variables with short names like t 20 PMD Marker
Unread field: CompassCanvas.switchVar 22 FindBugs
Unread field: CompassCanvas.switched 23 FindBugs
It is a good practice to call super() in a constructor 38 PMD Marker
Parameter 'mob' is not assigned and could be declared final 38 PMD Marker
Avoid empty catch blocks 53 PMD Marker
Avoid empty catch blocks 57 PMD Marker
Avoid really long methods. 63 PMD Marker
Avoid variables with short names like g 63 PMD Marker
Cyclomatic Complexity is 10 63 Metrics Marker
Parameter 'g' is not assigned and could be declared final 63 PMD Marker
The method 'paint' has a Cyclomatic Complexity of 17. 63 PMD Marker
The method paint() has an NCSS count of 144 63 PMD Marker
The method paint() has an NPath complexity of 4375 63 PMD Marker
Avoid unnecessary comparisons in boolean expressions 68 PMD Marker

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Zarko Acimovic

CompassCanvas.java violations - continued

Avoid unused local variables such as 'mediumX'. 122 PMD Marker
Dead store to mediumX in CompassCanvas.paint(Graphics) 122 FindBugs
The local variable mediumX is never read 122 Java Problem
Avoid unused local variables such as 'mediumY'. 123 PMD Marker
Dead store to mediumY in CompassCanvas.paint(Graphics) 123 FindBugs
The local variable mediumY is never read 123 Java Problem
Avoid unnecessary comparisons in boolean expressions 285 PMD Marker

CompassCanvas.java source code

1 /**
2 *
3 * ComapssCanvas draws compass on screen
4 */
5 import javax.microedition.lcdui.*;
6 //import javax.microedition.midlet.*;
7
8
9
10 public class CompassCanvas extends Canvas implements Runnable{
11 long north;
12 long south;
13 long east;
14 long west;
15 int bigRadius;
16 int smallRadius;
17 int smallestRadius;
18 Coordinates c;
19 long delta = 0;
20 Thread t;
21 boolean end = false;
22 boolean switchVar = false;
23 boolean switched = false;
24 MapObjects mob;
25
26 int dummy1 = 0;
27 int dummy2 = 0;
28 int dummy3 = 0;

xxx


29 int dummy4 = 0;
30 Image img;
31
32 Image imgDest;
33 long destUp;
34 long destDown;
35 long gama;
36
37
38 CompassCanvas(MapObjects mob){
39 this.mob = mob;
40 north = MathFP.toFP("0");
41 south = MathFP.div(Coordinates.MathFP_2PI,MathFP.toFP("2"));
42 east = MathFP.mul(Coordinates.MathFP_2PI,MathFP.toFP("0.25"));
43 west = MathFP.mul(Coordinates.MathFP_2PI,MathFP.toFP("0.75"));
44
45 destUp = MathFP.toFP("0");
46 destDown = MathFP.div(Coordinates.MathFP_2PI,MathFP.toFP("2"));
47
48 bigRadius = Math.min(this.getWidth(),this.getHeight());
49 smallRadius = (int)(0.75*bigRadius);
50 smallestRadius = (int)(0.37*bigRadius);
51 try{
52 img = Image.createImage("Arrow2.jpg");
53 }catch(Exception e){}
54
55 try{
56 imgDest = Image.createImage("Dest.jpg");
58
59 t = new Thread(this);
60 t.start();
61 }
62
63 public void paint(Graphics g){
64 //System.out.println("delta="+MathFP.toString(delta));
65 g.setColor(255,255,255);
66 g.fillRect(0,0,this.getWidth(),this.getHeight());
67 g.setColor(0,0,0);
68 if(end == false){
69 g.drawImage(img,75,25,0);
70
71
//System.out.println("this.getWidth()="+this.getWidth());
72
//System.out.println("this.getHeight()="+this.getHeight());
73 g.drawArc(8,0,bigRadius,bigRadius,0,360);
74 g.drawArc(30,22,smallRadius,smallRadius,0,360);
75

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76 String sx =
MathFP.toString(MathFP.add(MathFP.toFP(93),MathFP.mul(MathFP.toFP(75),MathFP.sin(Ma
thFP.sub(north,delta)))));
77 String sy =
MathFP.toString(MathFP.sub(MathFP.toFP(85),MathFP.mul(MathFP.toFP(75),MathFP.cos(Ma
thFP.sub(north,delta)))));
78 int ix = sx.indexOf('.');
79 sx = sx.substring(0,ix);
80 int iy = sy.indexOf('.');
81 sy = sy.substring(0,iy);
82
83 int x = Integer.parseInt(sx);
84 int y = Integer.parseInt(sy);
85
86 String s9 =
MathFP.toString(MathFP.add(MathFP.toFP(93),MathFP.mul(MathFP.toFP(smallestRadius),M
athFP.sin(MathFP.sub(north,delta)))));
87 ix = s9.indexOf('.');
88 s9 = s9.substring(0,ix);
89 int NX = Integer.parseInt(s9);
90 String s10 =
MathFP.toString(MathFP.sub(MathFP.toFP(85),MathFP.mul(MathFP.toFP(smallestRadius),M
athFP.cos(MathFP.sub(north,delta)))));
91 iy = s10.indexOf('.');
92 s10 = s10.substring(0,iy);
93 int NY = Integer.parseInt(s10);
94
95 g.drawString("N",x,y,0);
96
97 sx =
thFP.sub(south,delta)))));
98 sy =
thFP.sub(south,delta)))));
99 ix = sx.indexOf('.');
101 iy = sy.indexOf('.');
103
104 x = Integer.parseInt(sx);
105 y = Integer.parseInt(sy);
106
107 String s11 =
athFP.sin(MathFP.sub(south,delta)))));
108 ix = s11.indexOf('.');
110 int SX = Integer.parseInt(s11);

xxxii


111 String s12 =
athFP.cos(MathFP.sub(south,delta)))));
112 iy = s12.indexOf('.');
113 s12 = s12.substring(0,iy);
114 int SY = Integer.parseInt(s12);
115
116
117
118 g.drawString("S",x,y,0);
119 int del = 0;
120 g.drawLine(NX-del,NY-del,SX-del,SY-del);
121
122 int mediumX = (int)Math.abs((NX-SX)/2);
123 int mediumY = (int)Math.abs((NY-SY)/2);
124
125 String s1 =
thFP.sub(east,delta)))));
126 String s2 =
127
128 String s3 =
thFP.sub(west,delta)))));
129 String s4 =
130
133 dummy1 = Integer.parseInt(s1);
134
138
142
146
147 g.drawLine(NX-del,NY-del,dummy1,dummy2);
148 g.drawLine(dummy1,dummy2,SX-del,SY-del);
149 g.drawLine(NX-del,NY-del,dummy3,dummy4);
150 g.drawLine(dummy3,dummy4,SX-del,SY-del);
151

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152 sx =
153 sy =
158
161
162 g.drawString("E",x,y,0);
163
164 sx =
165 sy =
170
173
174 g.drawString("W",x,y,0);
175
176
177
178
179 gama = MathFP.sub(delta,gama);
180 //gama = MathFP.toFP("314");
181 long gamaDegrees =
Coordinates.radiansToDegrees(gama);
182 //long gamaDegrees = gama;
183
//System.out.println("gama="+MathFP.toString(gamaDegrees));
184 //gama = Coordinates.degreesToRadians(gama);
185
186 long corrX =
MathFP.add(MathFP.toFP(93),MathFP.mul(MathFP.toFP(smallestRadius),MathFP.sin(MathFP
.sub(destUp,gama))));
187 long corrY =
MathFP.sub(MathFP.toFP(85),MathFP.mul(MathFP.toFP(smallestRadius),MathFP.cos(MathFP
.sub(destUp,gama))));
188

xxxiv


189 long dx = 0;
190 long dy = 0;
191
192 if(gamaDegrees<=0) {
193 gama =
MathFP.add(gama,Coordinates.MathFP_2PI);
194 gamaDegrees =
MathFP.add(gamaDegrees,MathFP.toFP("360"));
195 }
196
197 // Correction of position for imgDest
198 if(MathFP.toFP("0")<=gamaDegrees && gamaDegrees
<MathFP.toFP("10")){
199 dx = 0-
MathFP.mul(MathFP.toFP("10"),MathFP.cos(gama));
200 dy = 0-
201 }
202
203
205 dx = 0-
206 dy = 0-
207 }
208
210 dx = 0-
211 dy = 0-
212 }
213
215 dx = 0-
MathFP.mul(MathFP.toFP("25"),MathFP.sin(gama));
216 dy = 0-
217 }
218
219 if(MathFP.toFP("85")<=gamaDegrees &&
gamaDegrees<MathFP.toFP("175")){
220 dx = 0-
221 dy = 0-
222 }

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223
224
gamaDegrees<MathFP.toFP("275")){
226 dx =
227 dy =
228 }
229
gamaDegrees<=MathFP.toFP("360")){
231 dx = 0-
232 dy = 0-
233
234 }
235
236
237
238
239 long prevCorrX=corrX;
240 long prevCorrY=corrY;
241
242 corrX = MathFP.add(corrX,dx);
243 corrY = MathFP.add(corrY,dy);
244
245
246
247 sx = MathFP.toString(corrX);
248 sy = MathFP.toString(corrY);
253 int xbear1 = Integer.parseInt(sx);
254 int ybear1 = Integer.parseInt(sy);
255
256
257 sx = MathFP.toString(prevCorrX);
258 sy = MathFP.toString(prevCorrY);
265
266
267

xxxvi


268 sx =
athFP.sin(MathFP.sub(destDown,gama)))));
269 sy =
athFP.cos(MathFP.sub(destDown,gama)))));
270
271
278
279 g.drawLine(xbear2,ybear2,xbear3,ybear3);
280 g.drawImage(imgDest,xbear1,ybear1,0);
281 }
282 }
283
284 public void run(){
285 while(end == false){
286 delta = mob.getDirection();
287 gama = mob.getBearing();
288 repaint();
289 try{
290 Thread.sleep(100);
292
293 }
294 }
295
296 public void setEnd(){
297 end = true;
298 }
299
300 }

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Coordinates.java violations

Lack of Cohesion in Methods (Pairwise Field Irrelation) is 100% 9 Metrics Marker
Lack of Cohesion in Methods (Total Correlation) is 100% 9 Metrics Marker
Parameter 'latitude' is not assigned and could be declared final 38 PMD Marker
Parameter 'longitude' is not assigned and could be declared final 38 PMD Marker
Parameter 'original' is not assigned and could be declared final 47 PMD Marker
Parameter 'latitude' is not assigned and could be declared final 74 PMD Marker
Parameter 'longitude' is not assigned and could be declared final 82 PMD Marker
Avoid variables with short names like to 92 PMD Marker
Local variable 'deltaLat' could be declared final 107 PMD Marker
Avoid using if...else statements without curly braces 127 PMD Marker
Avoid using if...else statements without curly braces 129 PMD Marker
Avoid variables with short names like to 148 PMD Marker

Coordinates.java source code

1 /**
2 *
3 * Coordinates class different performs geographical calculations
4 */
5
6
7
8 //import net.jscience.math.MathFP;
9 public class Coordinates {
10 /**
11 * Earth's radius (in meters)
12 */
13 public static final long EARTH_RADIUS = MathFP.toFP(6367000);
14 public static final long EARTH_RADIUS2 = MathFP.toFP(6367000*2);
15 /**
16 * the WGS-84 latitude of a location
17 */

xxxviii


18 private long latitude;
19 /**
20 * the WGS-84 longitude of a location
21 */
22 private long longitude;
23 /**
24 * The altitude of the location in meters, defined as height above WGS-84
ellipsoid. Float.NaN can be used to indicate that the altitude is not known.
25 */
26
27
28 /**
29 * Constructor
30 * @param latitude latitude as WGS-84 system coordinate
31 * @param longitude longitude as WGS-84 system coordinate
32 * @param altitude the altitude in meters, if known, or Float.NaN
33 * @param timestamp the time when information stored in this object
was created, in milliseconds since midnight January 1, 1970 GMT, or -1
34 * @param source the short string describing where data contained
in this object came from, like "GPS", "Network", "Database", etc
35 * @param horizontalAccuracy the horizontal accuracy of coordinates
in meters, or Float.NaN
36 * @param verticalAccuracy vertical accuracy of coordinates in
meters, or Float.NaN
37 */
38 public Coordinates(long latitude, long longitude){
39 this.latitude=latitude;
40 this.longitude=longitude;
41 }
42
43 /**
44 * Copy constructor
45 * @param original copied object
46 */
47 public Coordinates(Coordinates original){
48 this.latitude=original.latitude;
49 this.longitude=original.longitude;
50 }
51
52
53 /**
54 * The WGS-84 latitude of a location
55 * @return WGS-84 latitude
56 */
57 public long getLatitude(){
58 return latitude;
59 }
60
61 /**
62 * The WGS-84 longitude of a location
63 * @return WGS-84 longitude

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64 */
65 public long getLongitude(){
66 return longitude;
67 }
68
69
70 /**
71 * Set latitude as WGS-84 system coordinate.
72 * @param latitude latitude as WGS-84 system coordinate
73 */
74 public void setLatitude(long latitude){
75 this.latitude=latitude;
76 }
77
78 /**
79 * Set longitude as WGS-84 system coordinate.
80 * @param longitude longitude as WGS-84 system coordinate
81 */
82 public void setLongitude(long longitude){
83 this.longitude=longitude;
84 }
85
86 /**
87 * Calculate bearing to another location on the surface of the Earth,
using the Great Circle.
88 * bearing - 1.way of behaving 2.connection 3.direction shown by
compass 4.understanding of one's position
89 * @param to another point
90 * @return long representing angle in degrees [0,360) between
corresponding meridian in first point and line on the Great Circle between those
points
91 */
92 public long bearing(Coordinates to){
93 return bearing(getLatitude(), getLongitude(), to.getLatitude(),
to.getLongitude());
94 }
95 /**
96 * Calculate bearing between points (latFrom, lonFrom) and (latTo,lonTo)
on the surface of the Earth, using the Great Circle.
97 * @param latFrom latitude of the first point
98 * @param lonFrom longitude of the first point
99 * @param latTo latitude of the second point
100 * @param lonTo longitude of the second point
101 * @return long representing angle in degrees [0,360) between
corresponding meridian in first point and line on the Great Circle between those
points
102 */
103 protected static long bearing(long latFrom, long lonFrom, long latTo,
long lonTo){
104 //BMa: Some numeric with MathFP still happen - but error is mostly
below 16 degrees

xl


105 // This should be fixed only if the final target device stays without
not have floats or doubles (e.g. it is not CLDC 1.1)
106 long bearing;
107 long deltaLat=latTo-latFrom;
108 long deltaLon=lonTo-lonFrom;
109 if (MathFP.abs(deltaLat)<MathFP_1 && MathFP.abs(deltaLon)<MathFP_1) {
110 // longiude and latitude distance within one deegre, could invent
better condition
111 //This approximation works better for smaller distances
112 latFrom = degreesToRadians(latFrom);
113 deltaLon=MathFP.mul(deltaLon, MathFP.cos(latFrom));
114 bearing = MathFP.atan2(deltaLat,deltaLon);
115 }else{
117 latTo = degreesToRadians(latTo);
118 lonFrom = degreesToRadians(lonFrom);
119 lonTo = degreesToRadians(lonTo);
120
121
122 if (latFrom==latTo && lonFrom==lonTo)
123 return 0;
124 //if (MathFP.cos(latFrom) < Double.MIN_VALUE) // Double.MIN_VALUE a
small number ~ machine precision, so here we check for +/-0
125 if (MathFP.cos(latFrom) == 0 ) // Double.MIN_VALUE a small number ~
machine precision, so here we check for +/-0
126 if (latFrom > 0)
127 return MathFP.PI; // starting from N pole
128 else
129 return MathFP_2PI; // starting from S pole
130 //double bearing = radiansToDegrees(Math.atan2(Math.sin(lon2-
lon1)*Math.cos(lat2),Math.cos(lat1)*Math.sin(lat2)-
Math.sin(lat1)*Math.cos(lat2)*Math.cos(lon2-lon1))%(2*Math.PI));
131
132 bearing = MathFP.atan2(
133 MathFP.mul(MathFP.sin(deltaLon),MathFP.cos(latTo)),
134 MathFP.mul(MathFP.cos(latFrom),MathFP.sin(latTo))-
135
MathFP.mul(MathFP.mul(MathFP.sin(latFrom),MathFP.cos(latTo)),MathFP.cos(deltaLon)))
;
136 }
137 bearing = MathFP.mod(radiansToDegrees(bearing), MathFP_360);
138
139 if (bearing<0) bearing = MathFP_360 + bearing;
140 return bearing;
141 }
142
143 /**
144 * Calculate distance to another location on the surface of the Earth,
using the Great Circle.
145 * @param to another point

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146 * @return distance to another location in meters, using the line on the
Great Circle
147 */
148 public long distance(Coordinates to){
149 //BMa: Some numeric with MathFP are still possible - errors happen
sometimes
150 // This should be fixed only if the final target device stays without
not have floats or doubles (e.g. it is not CLDC 1.1)
151 return calculateDistance(getLatitude(), getLongitude(),
to.getLatitude(), to.getLongitude());
152 }
153
154 /**
155 * Calculate distance between points (latFrom, lonFrom) and (latTo,lonTo)
on the surface of the Earth, using the Great Circle.
156 * lat , lon - degrees ([-90, +90]; [-180, +180])
157 *
158 * @param latFrom latitude of the first point
159 * @param lonFrom longitude of the first point
160 * @param latTo latitude of the second point
161 * @param lonTo longitude of the second point
162 * @return distance to another location in meters, using the line on the
Great Circle
163 */
164 public static long calculateDistance(long latFrom, long lonFrom, long
latTo, long lonTo){
165 /*
166 * d=2*asin(sqrt((sin((latFrom-latTo)/2))^2 +
cos(latFrom)*cos(latTo)*(sin((lonFrom-lonTo)/2))^2))
167 * or
168 * d=2*asin(sqrt((sin((latFrom-latTo)/2))^2 +
cos(latFrom)*cos(latTo)*(sin((lonTo-lonFrom)/2))^2))
169 * distance = R*d
170 */
171
173 latTo = degreesToRadians(latTo);
174 lonFrom = degreesToRadians(lonFrom);
175 lonTo = degreesToRadians(lonTo);
176 //long distance = R * MathFP.acos(MathFP.sin(latFrom)*MathFP.sin(latTo)
+ MathFP.cos(latFrom)*MathFP.cos(latTo)*MathFP.cos(lonTo-lonFrom));
177 /*
178 double distance = R * 2 * Math.asin(
179 Math.sqrt(
180 Math.pow(Math.sin((lat1-lat2)/2), 2)
181 +
182
Math.cos(lat1)*Math.cos(lat2)*Math.pow(Math.sin((lon2-lon1)/2), 2)
183 )
184 );
185 */

xlii


186
187 /*
188 System.out.print("latFrom: "+MathFP.toString(latFrom));
189 System.out.println(" lonFrom: "+MathFP.toString(lonFrom));
190 System.out.print("latTo: "+MathFP.toString(latTo));
191 System.out.println(" lonTo: "+MathFP.toString(lonTo));
192 */
193
194 long p1=MathFP.sin(MathFP.div((latFrom-latTo), MathFP_2));
195 p1 = MathFP.mul(p1, MathFP.toFP(1000000));
196 //System.out.println(" p1: "+MathFP.toString(p1));
197 p1 = MathFP.mul(p1, p1);
199
200 long p2=MathFP.sin(MathFP.div((lonTo-lonFrom), MathFP_2));
201 p2 = MathFP.mul(p2, MathFP.toFP(1000000));
203 p2 = MathFP.mul(p2, p2);
205
206 long sqrtarg=p1
+MathFP.mul(MathFP.mul(MathFP.cos(latFrom),MathFP.cos(latTo)),p2);
207 //System.out.println(" sqrtarg: "+MathFP.toString(sqrtarg));
208
209 sqrtarg=MathFP.sqrt(sqrtarg);
210 //System.out.println(" sqrtarg: "+MathFP.toString(sqrtarg));
211
212 long distance;
213 if (sqrtarg>MathFP.toFP(19000)) { //toFP("0.019")*1000000 - boundary
for MathFP.asin approximation by X
214 // calculation is erroneus for small angles
215 long asinarg=MathFP.div(sqrtarg, MathFP.toFP(1000000));
216 //System.out.println(" > asinarg: "+MathFP.toString(asinarg));
217 asinarg=MathFP.asin(asinarg);
218 //System.out.println(" > asinarg: "+MathFP.toString(asinarg));
219 distance = MathFP.mul(EARTH_RADIUS2, asinarg);
220 //System.out.println(" distance asin: "+MathFP.toString(distance));
221 } else {
222 //asin(X) is aproximately equall to X,
223 //This approximation allow us to change the order of multiplication
and division in order to reduce loss of significant digits
224
225 distance = MathFP.mul(EARTH_RADIUS2, sqrtarg);
226 //System.out.println(" > distance: "+MathFP.toString(distance));
227 distance=MathFP.div(distance, MathFP.toFP(1000000));
228
229 }
230
231 //System.out.println(" distance: "+MathFP.toString(distance));
232
233 //if (Double.isNaN(distance)) //equivalent to (distance=0), but safer

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234 // return 0;
235 return distance;
236 }
237
238
239 /**
240 * Convert degrees to radians
241 * @return value transformed to radians
242 * @param degrees value to be transformed to radians
243 */
244 public static long degreesToRadians(long degrees){
245 return MathFP.div(degrees,MathFP_180DivPI);
246 }
247
248 /**
249 * Convert radians to degrees
250 * @return value transformed to degrees
251 * @param radians value to be transformed to degrees
252 */
253 public static long radiansToDegrees(long radians){
254 return MathFP.mul(radians,MathFP_180DivPI);
255 }
256
257 public static final long MathFP_2 = MathFP.toFP(2);
259 public static final long MathFP_2PI = MathFP.mul(MathFP_2, MathFP.PI);
262 public static final long MathFP_180DivPI = MathFP.div(MathFP.toFP(180),
MathFP.PI);
263 public static final long MathFP_0_5 = MathFP.toFP("0.5");
264
265
266 }

xliv


DelRoute.java violations

Parameter 'index' is not assigned and could be declared final 8 PMD Marker
Parameter 'routeID' is not assigned and could be declared final 8 PMD Marker

1 /**
2 *
3 * DelRoute is used when deleting route
4 */
5 public class DelRoute {
6 int index;
7 int routeID;
8 DelRoute(int index, int routeID){
9 this.index = index;
10 this.routeID = routeID;
11 }
12 int getIndex(){
13 return index;
14 }
15 int getRouteID(){
16 return routeID;
17 }
18
19 public String toString(){
20 return "ID Route is "+routeID+"n"+"Index of element to
delet is "+index;
21 }
22
23 }

xlv

Zarko Acimovic

Friend.java violations

Lack of Cohesion in Methods (Total Correlation) is 107% 5 Metrics Marker
Parameter 'hashThread' is not assigned and could be declared final 11 PMD Marker
Parameter 'name' is not assigned and could be declared final 11 PMD Marker
Parameter 'resource' is not assigned and could be declared final 11 PMD Marker
Parameter 't' is not assigned and could be declared final 11 PMD Marker
Parameter 'hash' is not assigned and could be declared final 30 PMD Marker
A getX() method which returns a boolean should be named isX() 42 PMD Marker

1 /**
2 *
3 * Friend class holds all important data for a friend
4 */
5 public class Friend {
6 String name;
7 String resource;
8 int hashThread;
9 Thread4Friend t;
10
11 Friend(String name, String resource, int hashThread, Thread4Friend
t){
12 this.name = name;
13 this.resource = resource;
14 this.hashThread = hashThread;
15 this.t = t;
16 }
17
18 public String getName(){
19 return name;
20 }
21
22 public String getResource(){

xlvi


23 return resource;
24 }
25
26 public int getHash(){
27 return hashThread;
28 }
29
30 public void setID(int hash){
31 hashThread = hash;
32 }
33
34 public String toString(){
35 return "Friend is "+name+"n"+"Hash is "+hashThread;
36 }
37
38 public void setFirst(){
39 t.setFirst();
40 }
41
42 public boolean getThread(){
43 if (t==null){ return false; }
44 else {return true; }
45 }
46
47 public void setThread(Thread4Friend t){
48 this.t = t;
49 }
50 }

xlvii

Zarko Acimovic

HeapSorter.java violations

This class has too many methods, consider refactoring it. 5 PMD Marker
Document empty constructor 7 PMD Marker
Avoid variables with short names like a 9 PMD Marker
Avoid variables with short names like A 10 PMD Marker
Avoid variables with short names like as 23 PMD Marker
Avoid variables with short names like AS 24 PMD Marker
Prefer StringBuffer over += for concatenating strings 30 PMD Marker
Avoid variables with short names like a 37 PMD Marker
Parameter 'a' is not assigned and could be declared final 37 PMD Marker
Avoid using for statements without curly braces 38 PMD Marker
Parameter 'as' is not assigned and could be declared final 41 PMD Marker
Avoid using for statements without curly braces 42 PMD Marker
Parameter 'i' is not assigned and could be declared final 45 PMD Marker
Local variable 'l' could be declared final 46 PMD Marker
Local variable 'r' could be declared final 47 PMD Marker
Local variable 'tmp' could be declared final 62 PMD Marker
Parameter 'i' is not assigned and could be declared final 67 PMD Marker
Local variable 'l' could be declared final 68 PMD Marker

1 /**
2 *
3 * HeapSorter class sorts points by distance or by name
4 */
5 public class HeapSorter{
6
7 HeapSorter(){}
8
9 public void heapsort(long[] a){
10 long[]A = setHeapWithSize(a,a.length);
11 buildHeap(A);
12 for(int i=0; i<A.length; i++){
13 System.out.println(A[i]);
14 }
15 for(int i=a.length; i>1; i--){
16 a[i-1]=A[0]; A[0]=A[i-1];
17 A=setHeapWithSize(A,A.length-1);
18 heapify(A,1);
19 }

xlviii


20 a[0]=A[0];
21 }
22
23 public void heapsort(String[] as){
24 String[] AS = setHeapWithSize(as,as.length);
25 buildHeap(AS);
26 for(int i=0; i<AS.length; i++){
27 System.out.println(AS[i]);
28 }
29 for(int i=as.length; i>1; i--){
30 as[i-1]=AS[0]; AS[0]=AS[i-1];
31 AS=setHeapWithSize(AS,AS.length-1);
32 heapify(AS,1);
33 }
34 as[0]=AS[0];
35 }
36
37 public void buildHeap(long[] a){
38 for(int i=a.length/2; i>0; i--) heapify(a,i);
39 }
40
41 public void buildHeap(String[] as){
42 for(int i=as.length/2; i>0; i--) heapify(as,i);
43 }
44
45 public void heapify(long[]a, int i){
46 int l=left(i);
47 int r=right(i);
48 int largest;
49
50 if(l<=heapSize(a) && a[l-1]>a[i-1]){
51 largest=l;
52 }else{
53 largest=i;
54 }
55
56 if(r<=heapSize(a) && a[r-1]>a[largest-1]){
57 largest=r;
58 }
59
60 if(largest!=i){
61 //exchange a[i], a[largest]
62 long tmp=a[i-1]; a[i-1]=a[largest-1]; a[largest-
1]=tmp;
63 heapify(a,largest);
64 }
65 }
66
67 public void heapify(String[]as, int i){
68 int l=left(i);
69 int r=right(i);

xlix

Zarko Acimovic

70 int largest;
71
72 if(l<=heapSize(as) && as[l-1].charAt(0)>as[i-1].charAt(0)){
73 largest=l;
74 }else{
75 largest=i;
76 }
77
78 if(r<=heapSize(as) && as[r-1].charAt(0)>as[largest-
1].charAt(0)){
79 largest=r;
80 }
81
82 if(largest!=i){
83 //exchange a[i], a[largest]
84 String tmpS=as[i-1]; as[i-1]=as[largest-1];
as[largest-1]=tmpS;
85 heapify(as,largest);
86 }
87 }
88
89
90 public int heapSize(long a[]){
91 return a.length;
92 }
93
94 public int heapSize(String as[]){
95 return as.length;
96 }
97
98 public int parent(int i){
99 return(i/2);
100 }
101
102 public int left(int i){
103 return(2*i);
104 }
105
106 public int right(int i){
107 return(2*i+1);
108 }
109
110 public long[] setHeapWithSize(long[]m , int n){
111 long[] k = new long[n];
112 for(int i=0; i<n; i++){
113 k[i]=m[i];
114 }
115 return k;
116 }
117
118 public String[] setHeapWithSize(String[]m , int n){

l


119 String[] k = new String[n];
120 for(int i=0; i<n; i++){
121 k[i]=m[i];
122 }
123 return k;
124 }
125 };

ImageCanvas3.java violations

Avoid variables with short names like ol 12 PMD Marker
Avoid variables with short names like ol 14 PMD Marker
It is a good practice to call super() in a constructor 14 PMD Marker
Parameter 'ol' is not assigned and could be declared final 14 PMD Marker
Avoid variables with short names like g 19 PMD Marker
Parameter 'g' is not assigned and could be declared final 19 PMD Marker
Parameter 'keyCode' is not assigned and could be declared final 23 PMD Marker

1 /**
2 *
3 * ImageCanvas3 draws elements on screen and captures events on canvas
4 */
5
6 //import java.io.IOException;
7 import javax.microedition.lcdui.*;
8 //import java.util.*;
9
10 public class ImageCanvas3 extends Canvas {
11
12 Outlook ol;
13
14 ImageCanvas3(Outlook ol){
15 this.ol =ol;
16 ol.setCanvasWH(this.getWidth(),this.getHeight());
17 }
18
19 public void paint(Graphics g) {
20 ol.drawOutlook(g);
21 }

li

Zarko Acimovic

22
23 public void keyPressed (int keyCode){
24
25 //keyCode+=disabler;
26
27 if(keyCode==49){
28 ol.ZoomIn();
29 repaint();
30 }
31
32 if(keyCode==50){
33 ol.ZoomOut();
34 repaint();
35 }
36
37 if(keyCode==51){
38 repaint();
39 }
40
41
42 switch (getGameAction(keyCode)) {
43 case Canvas.UP:
44 ol.setMap('u');
45 repaint();
46 break;
47 case Canvas.DOWN:
48 ol.setMap('d');
49 repaint();
50 break;
51 case Canvas.LEFT:
52 ol.setMap('l');
53 repaint();
54 break;
55 case Canvas.RIGHT:
56 ol.setMap('r');
57 repaint();
58 break;
59 }
60 }
61 }

lii

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