Smalltalk 语言 抽象类与接口的使用实战

Smalltalk阿木 发布于 16 天前 4 次阅读

Smalltalk【1】 语言中抽象类【2】与接口【3】的使用实战

Smalltalk 是一种面向对象的编程语言，它以其简洁的语法和强大的对象模型而闻名。在 Smalltalk 中，抽象类和接口是构建可扩展和可维护代码的关键概念。本文将深入探讨 Smalltalk 中抽象类与接口的使用，并通过实际代码示例来展示如何在项目中应用这些概念。

抽象类与接口概述

在面向对象编程【4】中，抽象类和接口都是用来定义一组方法【5】，这些方法可以在子类中实现或继承。它们的主要区别在于：

- 抽象类：可以包含具体实现的方法，也可以包含抽象方法（没有实现的方法）。抽象类通常用于定义一个类的基本结构，并提供一些默认实现。
- 接口：只包含抽象方法，没有具体实现。接口用于定义一组规范，实现这些规范的具体类可以由其他开发者提供。

在 Smalltalk 中，抽象类和接口的概念通过类和协议【6】来实现。

Smalltalk 中的类

在 Smalltalk 中，类是对象的基础。每个类都定义了一组属性【7】和方法。以下是一个简单的 Smalltalk 类定义示例：

```smalltalk
Class: Person

Attributes:
name: String

Methods:
initialize: aName
| name |
name := aName.
^ self

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