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You're reading from  Kotlin Design Patterns and Best Practices - Second Edition

Product typeBook
Published inJan 2022
Reading LevelBeginner
PublisherPackt
ISBN-139781801815727
Edition2nd Edition
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Author (1)
Alexey Soshin
Alexey Soshin
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Alexey Soshin

Alexey Soshin is a software architect with 15 years of experience in the industry. He started exploring Kotlin when Kotlin was still in beta, and since then has been a big enthusiast of the language. He's a conference speaker, published writer, and the author of a video course titled Pragmatic System Design.
Read more about Alexey Soshin

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Prototype

The Prototype design pattern is all about customization and creating objects that are similar but slightly different. To understand it better, Let's look at an example.

Imagine we have a system that manages users and their permissions. A data class representing a user might look like this:

data class User(
    val name: String,
    val role: Role,
    val permissions: Set<String>,
) {
    fun hasPermission(permission: String) = permission in       permissions
}

Each user must have a role, and each role has a set of permissions.

We'll describe a role as an enum class:

enum class Role {
    ADMIN,
    SUPER_ADMIN,
    REGULAR_USER
}

The enum classes are a way to represent a collection of constants. This is more convenient than representing a role as a string, for example, as...

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Kotlin Design Patterns and Best Practices - Second Edition
Published in: Jan 2022Publisher: PacktISBN-13: 9781801815727

Author (1)

author image
Alexey Soshin

Alexey Soshin is a software architect with 15 years of experience in the industry. He started exploring Kotlin when Kotlin was still in beta, and since then has been a big enthusiast of the language. He's a conference speaker, published writer, and the author of a video course titled Pragmatic System Design.
Read more about Alexey Soshin