CSC309 Lecture 09

Software Engineering II
Pair Programming
(202301)

Transcript

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   CSC 309
   Software Engineering II
   Lecture 09: Pair Programming
   Dr. Javier Gonzalez-Sanchez
   javiergs@calpoly.edu
   users.csc.calpoly.edu/~javiergs | javiergs.com
   Building 14 -227
   Office Hours: By appointment
   

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   Previously …
   

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   Fall 2022 | 00000001
   Key Ideas CSC 309
   idea
   requirements
   architecture
   design
   code
   quality measure
   

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   Pair Programming
   Reference:
   On Pair Programming by Martin Fowler (Agile, Architecture, Refactoring)
   https://martinfowler.com/articles/on-pair-programming.html
   

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   § Best programs and designs are done in pairs because you can
   criticize each other, find each other’s errors, and use the best ideas.
   - Jean Bartik (one of the very first programmers)
   § Write all production programs with two people sitting at one machine.
   - Kent Beck (Agile, JUnit)
   Pair Programming
   

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   Process
   § The process starts with the developers receiving a well-defined task.
   § They agree on one small goal at a time.
   § They take turns to code or review each other's work.
   § Rotating roles regularly helps keep both developers alert and engaged.
   § Enable senior developers to share their knowledge and working habits
   § Help new team members get up to speed on a project.
   

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   Roles
   § Driver (the person on the keyboard). Focused on completing the tiny goal at
   hand, ignoring larger issues for the moment. A driver should always talk
   through what they are doing while doing it.
   § Navigator (the person observing). They review the code on the go, gives
   directions, and shares thoughts. They have an eye on the larger issues, and
   bugs, and make notes of potential next steps or obstacles. They are in
   control of the strategic or architectural elements. As a navigator, leave the
   details of the coding to the driver – your job is to take a step back and
   complement the driver’s tactical mode with medium-term thinking.
   

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   Problem
   • Equally engaging pairs. If both developers do not equally engage in the
   project, then there is less chance that knowledge will be shared
   • Social and interactive process. It is hard for those who work better alone.
   

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   In general
   

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    So, best practices
    • Consistent communication
    • Switch roles
    • Pair up carefully (select your pair).
    • A familiar development environment
    • Work at a pace that fits both developers.
    

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    A well-defined task
    We can use a compiler for our project
    

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    Part 1
    1. Read a File and Split the lines
    2. For each line read character by character
    3. Concatenate characters, creating the largest STRING
    possible. Stop when a delimiter, white space, operator, or
    quotation mark is found. If there are more characters in the
    line, go to step 2.
    4. Bonus points: for each STRING report its TYPE as correspond.
    E.g., class is a keyword, { is a delimiter, hello is a name
    (identifier), Student is a name (identifier), + is an operator,
    extends is a keyword, etc.
    

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    Part 2
    public class Parser {
    private static Vector tokens;
    private static int currentToken;
    public static void rule_class () {}
    public static void rule_body () {}
    public static void rule_global_variable () {}
    public static void rule_method () {}
    public static void rule_instruction () {}
    public static void rule_local_variable () {}
    public static void rule_call_method () {}
    public static void rule_assignment () {}
    public static void rule_operation () {} // ignore precedence
    public static void rule_operand() {}
    }
    

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    Let’s Work
    

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    Test Yourselves
    

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    Case 1
    class Student{}
    Input:
    You have 1 class.
    Classes:
    * Student
    Methods:
    Relationships:
    Output:
    

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    Case 2
    class Student{
    Hello world
    }
    Input:
    You have 2 class.
    Classes:
    * Student
    * Hello
    Methods:
    Relationships:
    * Student has a Hello
    Output:
    

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    Case 3
    class Student extends Person{
    Hello world
    }
    Input:
    You have 3 classes.
    Classes:
    * Student
    * Person
    * Hello
    Methods:
    Relationships:
    * Student has a Hello
    * Student is a Person
    Output:
    

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    Case 3
    class Student extends Person{
    Hello world
    }
    Input:
    You have 3 classes.
    Classes:
    * Student
    * Person
    * Hello
    Methods:
    Relationships:
    * Student has a Hello
    * Student is a Person
    Output:
    

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    Case 4
    class Student extends Person{
    Hello world() {
    }
    }
    Input:
    You have 2 classes.
    Classes:
    * Student
    * Person
    Methods:
    * world
    Relationships:
    * Student is a Person
    Output:
    

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    Questions
    

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    CSC 309
    Software Engineering II
    Lab 09: Code Review
    Dr. Javier Gonzalez-Sanchez
    javiergs@calpoly.edu
    users.csc.calpoly.edu/~javiergs | javiergs.com
    Building 14 -227
    Office Hours: By appointment
    

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    Think about this
    1. Select your pair
    2. Understand the task
    (described before)
    3. Chose and set up your
    environment
    4. Be ready to work
    

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    Let’s Work
    

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    CSC 309 Software Engineering II
    Javier Gonzalez-Sanchez, Ph.D.
    javiergs@calpoly.edu
    Winter 2023
    Copyright. These slides can only be used as study material for the class CSC308 at Cal Poly.
    They cannot be distributed or used for another purpose.
    

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