dylan-video-club

Example from 'Refactoring' book of Martin Fowler.

Video-club example

I re-do the first example in Martin Fowler's book "Refactoring: Improving the design of existing code" edition 1, in Opendylan.

Start diagram

The initial interaction for the method statement is shown in the next figure:

sequenceDiagram
    actor User
    User ->>customer: statement
    loop for all rentals
        customer->>rental: rental-movie
        customer->>movie: movie-price-code
        customer->>rental: rental-days-rented
    end

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Finish diagram

The translation between a multi-method Object Oriented programming and the sequence diagram is not 1 to 1. For instance category is not a class but a symbol.

sequenceDiagram
    actor User
    User ->>+statement: print-statement
    statement->>+customer: charge
    loop for all rentals
        customer->>+rental: charge
        rental->>+movie: charge-by-movie-and-days
        movie->>+category: charge-by-category-and-days
        category-->-movie: amount
        movie-->>-rental: amount
        rental-->>-customer: amount
    end
    statement->>+customer: rental-points
    loop for all rentals
        customer->>+rental: renter-points
        rental->>+movie: renter-points-by-movie-and-days
        movie-->>-rental: points
        rental-->>-customer: points 
    end

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