Coming up: Software Engineering: A Practitioner’s Approach, 6/e Chapter 5 Practice: A Generic View copyright © 1996, 2001, 2005 R.S. Pressman & Associates, Inc. For University Use Only May be reproduced ONLY for student use at the university level when used in conjunction with Software Engineering: A Practitioner's Approach. Any other reproduction or use is expressly prohibited. 1 Supplementary Slides for Software Engineering: A Practitioner's Approach, 6/e Part 2 Supplementary Slides for Software Engineering: A Practitioner's Approach, 6/e Part 2 copyright © 1996, 2001, 2005 R.S. Pressman & Associates, Inc. For University Use Only May be reproduced ONLY for student use at the university level when used in conjunction with Software Engineering: A Practitioner's Approach. Any other reproduction or use is expressly prohibited. This presentation, slides, or hardcopy may NOT be used for short courses, industry seminars, or consulting purposes.

Coming up: What is “Practice”? 2 Software Engineering: A Practitioner’s Approach, 6/e Chapter 5 Practice: A Generic View Software Engineering: A Practitioner’s Approach, 6/e Chapter 5 Practice: A Generic View copyright © 1996, 2001, 2005 R.S. Pressman & Associates, Inc. For University Use Only May be reproduced ONLY for student use at the university level when used in conjunction with Software Engineering: A Practitioner's Approach. Any other reproduction or use is expressly prohibited.

Coming up: The Essence of Practice 3 What is “Practice”? Practice is a broad array of concepts, principles, methods, and tools that you must consider as software is planned and developed. Practice is a broad array of concepts, principles, methods, and tools that you must consider as software is planned and developed. It represents the details—the technical considerations and how to’s—that are below the surface of the software process—the things that you’ll need to actually build high-quality computer software. It represents the details—the technical considerations and how to’s—that are below the surface of the software process—the things that you’ll need to actually build high-quality computer software.

Coming up: Core Software Engineering Principles 4 The Essence of Practice George Polya, in a book written in 1945 (!), describes the essence of software engineering practice … George Polya, in a book written in 1945 (!), describes the essence of software engineering practice … Understand the problem (communication and analysis). Understand the problem (communication and analysis). Plan a solution (modeling and software design). Plan a solution (modeling and software design). Carry out the plan (code generation). Carry out the plan (code generation). Examine the result for accuracy (testing and quality assurance). Examine the result for accuracy (testing and quality assurance). At its core, good practice is common-sense problem solving At its core, good practice is common-sense problem solving

Coming up: Software Engineering Practices 5 Core Software Engineering Principles Provide value to the customer and the user Provide value to the customer and the user KIS—keep it simple! KIS—keep it simple! Maintain the product and project “vision” Maintain the product and project “vision” What you produce, others will consume What you produce, others will consume Be open to the future Be open to the future Plan ahead for reuse Plan ahead for reuse Think! Think!

Coming up: Communication Practices 6 Software Engineering Practices Consider the generic process framework Consider the generic process framework Communication Communication Planning Planning Modeling Modeling Construction Construction Deployment Deployment Here, we’ll identify Here, we’ll identify Underlying principles Underlying principles How to initiate the practice How to initiate the practice An abbreviated task set An abbreviated task set

Coming up: Communication Practices 7 Communication Practices Principles Principles Listen Listen Prepare before you communicate Prepare before you communicate Facilitate the communication Facilitate the communication Face-to-face is best Face-to-face is best Take notes and document decisions Take notes and document decisions Collaborate with the customer Collaborate with the customer Stay focused Stay focused Draw pictures when things are unclear Draw pictures when things are unclear Move on … Move on … Negotiation works best when both parties win. Negotiation works best when both parties win.

Coming up: Planning Practices 8 Communication Practices Initiation Initiation The parties should be physically close to one another The parties should be physically close to one another Make sure communication is interactive Make sure communication is interactive Create solid team “ecosystems” Create solid team “ecosystems” Use the right team structure Use the right team structure An abbreviated task set An abbreviated task set Identify who it is you need to speak with Identify who it is you need to speak with Define the best mechanism for communication Define the best mechanism for communication Establish overall goals and objectives and define the scope Establish overall goals and objectives and define the scope Get more detailed Get more detailed Have stakeholders define scenarios for usage Have stakeholders define scenarios for usage Extract major functions/features Extract major functions/features Review the results with all stakeholders Review the results with all stakeholders

Coming up: Planning Practices 9 Planning Practices Principles Principles Understand the project scope Understand the project scope Involve the customer (and other stakeholders) Involve the customer (and other stakeholders) Recognize that planning is iterative Recognize that planning is iterative Estimate based on what you know Estimate based on what you know Consider risk Consider risk Be realistic Be realistic Adjust granularity as you plan Adjust granularity as you plan Define how quality will be achieved Define how quality will be achieved Define how you’ll accommodate changes Define how you’ll accommodate changes Track what you’ve planned Track what you’ve planned

Coming up: Planning Practices 10 Planning Practices Initiation Initiation Ask Boehm’s questions Ask Boehm’s questions Why is the system begin developed? Why is the system begin developed? What will be done? What will be done? When will it be accomplished? When will it be accomplished? Who is responsible? Who is responsible? Where are they located (organizationally)? Where are they located (organizationally)? How will the job be done technically and managerially? How will the job be done technically and managerially? How much of each resource is needed? How much of each resource is needed?

Coming up: Modeling Practices 11 Planning Practices An abbreviated task set An abbreviated task set Re-assess project scope Re-assess project scope Assess risks Assess risks Evaluate functions/features Evaluate functions/features Consider infrastructure functions/features Consider infrastructure functions/features Create a coarse granularity plan Create a coarse granularity plan Number of software increments Number of software increments Overall schedule Overall schedule Delivery dates for increments Delivery dates for increments Create fine granularity plan for first increment Create fine granularity plan for first increment Track progress Track progress

Coming up: Analysis Modeling Practices 12 Modeling Practices We create models to gain a better understanding of the actual entity to be built We create models to gain a better understanding of the actual entity to be built Analysis models represent the customer requirements by depicting the software in three different domains: the information domain, the functional domain, and the behavioral domain. Analysis models represent the customer requirements by depicting the software in three different domains: the information domain, the functional domain, and the behavioral domain. Design models represent characteristics of the software that help practitioners to construct it effectively: the architecture, the user interface, and component-level detail. Design models represent characteristics of the software that help practitioners to construct it effectively: the architecture, the user interface, and component-level detail.

Coming up: Design Modeling Practices 13 Analysis Modeling Practices Analysis modeling principles Analysis modeling principles Represent the information domain Represent the information domain Represent software functions Represent software functions Represent software behavior Represent software behavior Partition these representations Partition these representations Move from essence toward implementation Move from essence toward implementation Elements of the analysis model (Chapter 8) Elements of the analysis model (Chapter 8) Data model Data model Flow model Flow model Class model Class model Behavior model Behavior model

Coming up: Construction Practices 14 Design Modeling Practices Principles Principles Design must be traceable to the analysis model Design must be traceable to the analysis model Always consider architecture Always consider architecture Focus on the design of data Focus on the design of data Interfaces (both user and internal) must be designed Interfaces (both user and internal) must be designed Components should exhibit functional independence Components should exhibit functional independence Components should be loosely coupled Components should be loosely coupled Design representation should be easily understood Design representation should be easily understood The design model should be developed iteratively The design model should be developed iteratively Elements of the design model Elements of the design model Data design Data design Architectural design Architectural design Component design Component design Interface design Interface design

Coming up: Construction Practices 15 Construction Practices Preparation principles: Before you write one line of code, be sure you: Preparation principles: Before you write one line of code, be sure you: Understand of the problem you’re trying to solve (see communication and modeling) Understand of the problem you’re trying to solve (see communication and modeling) Understand basic design principles and concepts. Understand basic design principles and concepts. Pick a programming language that meets the needs of the software to be built and the environment in which it will operate. Pick a programming language that meets the needs of the software to be built and the environment in which it will operate. Select a programming environment that provides tools that will make your work easier. Select a programming environment that provides tools that will make your work easier. Create a set of unit tests that will be applied once the component you code is completed Create a set of unit tests that will be applied once the component you code is completed.

Coming up: Construction Practices 16 Construction Practices Coding principles: As you begin writing code, be sure you: Coding principles: As you begin writing code, be sure you: Constrain your algorithms by following structured programming [BOH00] practice. Constrain your algorithms by following structured programming [BOH00] practice. Select data structures that will meet the needs of the design. Select data structures that will meet the needs of the design. Understand the software architecture and create interfaces that are consistent with it. Understand the software architecture and create interfaces that are consistent with it. Keep conditional logic as simple as possible. Keep conditional logic as simple as possible. Create nested loops in a way that makes them easily testable. Create nested loops in a way that makes them easily testable. Select meaningful variable names and follow other local coding standards. Select meaningful variable names and follow other local coding standards. Write code that is self-documenting. Write code that is self-documenting. Create a visual layout (e.g., indentation and blank lines) that aids understanding. Create a visual layout (e.g., indentation and blank lines) that aids understanding.

Coming up: Construction Practices 17 Construction Practices Validation Principles: After you’ve completed your first coding pass, be sure you: Validation Principles: After you’ve completed your first coding pass, be sure you: Conduct a code walkthrough when appropriate. Conduct a code walkthrough when appropriate. Perform unit tests and correct errors you’ve uncovered. Perform unit tests and correct errors you’ve uncovered. Refactor the code. Refactor the code.

Coming up: Deployment Practices 18 Construction Practices Testing Principles Testing Principles All tests should be traceable to requirements All tests should be traceable to requirements Tests should be planned Tests should be planned The Pareto Principle (80-20 rule) applies to testing The Pareto Principle (80-20 rule) applies to testing Testing begins “in the small” and moves toward “in the large” Testing begins “in the small” and moves toward “in the large” Exhaustive testing is not possible Exhaustive testing is not possible

Coming up: Deployment Practices 19 Deployment Practices Principles Principles Manage customer expectations for each increment Manage customer expectations for each increment A complete delivery package should be assembled and tested A complete delivery package should be assembled and tested A support regime should be established A support regime should be established Instructional materials must be provided to end-users Instructional materials must be provided to end-users Buggy software should be fixed first, delivered later Buggy software should be fixed first, delivered later