{"id":4154,"date":"2023-04-18T11:53:00","date_gmt":"2023-04-18T14:53:00","guid":{"rendered":"https:\/\/elemarjr.com\/clube-de-estudos\/?p=4154"},"modified":"2023-10-21T21:40:12","modified_gmt":"2023-10-22T00:40:12","slug":"como-os-padroes-de-projeto-podem-ajudar-na-construcao-de-software","status":"publish","type":"artigos","link":"https:\/\/elemarjr.com\/clube-de-estudos\/artigos\/como-os-padroes-de-projeto-podem-ajudar-na-construcao-de-software\/","title":{"rendered":"Como os Padr\u00f5es de Projeto podem ajudar na constru\u00e7\u00e3o de Software"},"content":{"rendered":"\n

Como desenvolvedor de software, voc\u00ea provavelmente j\u00e1 ouviu falar em Design Patterns<\/strong>, ou Padr\u00f5es de Projeto em portugu\u00eas. Eles s\u00e3o uma abordagem que permite criar solu\u00e7\u00f5es eficientes e reutiliz\u00e1veis para problemas comuns de programa\u00e7\u00e3o. Neste artigo, vamos falar sobre como os Design Patterns podem ajudar na constru\u00e7\u00e3o de software.<\/p>\n\n\n\n

Os Design Patterns s\u00e3o solu\u00e7\u00f5es testadas e comprovadas para problemas espec\u00edficos de programa\u00e7\u00e3o. Eles foram criados por desenvolvedores experientes que identificaram problemas comuns em seus projetos e encontraram solu\u00e7\u00f5es eficientes e reutiliz\u00e1veis para esses problemas. Essas solu\u00e7\u00f5es foram documentadas e categorizadas em Design Patterns, permitindo que outros desenvolvedores possam implement\u00e1-las em seus pr\u00f3prios projetos.<\/p>\n\n\n\n

Existem diversos tipos de Design Patterns, cada um com uma fun\u00e7\u00e3o espec\u00edfica. Alguns exemplos incluem:<\/p>\n\n\n\n

Singleton<\/h2>\n\n\n\n

O Singleton \u00e9 um Design Pattern que garante que uma classe tenha apenas uma inst\u00e2ncia em todo o programa. Isso \u00e9 \u00fatil para classes que representam recursos caros ou que precisam ter um estado consistente em todo o programa. Veja exemplos de implementa\u00e7\u00e3o em C#, Java e Python:<\/p>\n\n\n\n

C#<\/span><\/path><\/path><\/svg><\/span>
public<\/span> <\/span>class<\/span> <\/span>Singleton<\/span><\/span>\n{<\/span><\/span>\n    <\/span>private<\/span> <\/span>static<\/span> Singleton __instance <\/span>=<\/span> <\/span>null;<\/span><\/span>\n<\/span>\n    <\/span>private<\/span> <\/span>Singleton<\/span>()<\/span><\/span>\n    <\/span>{<\/span><\/span>\n        <\/span>if<\/span> <\/span>(<\/span>__instance<\/span> <\/span>!=<\/span> <\/span>null<\/span>)<\/span><\/span>\n        <\/span>{<\/span><\/span>\n            <\/span>throw<\/span> <\/span>new<\/span> Exception<\/span>(<\/span>"<\/span>Singleton cannot be instantiated more than once<\/span>"<\/span>)<\/span>;<\/span><\/span>\n        <\/span>}<\/span><\/span>\n        <\/span>else<\/span><\/span>\n        <\/span>{<\/span><\/span>\n            <\/span>__instance<\/span> <\/span>=<\/span> <\/span>this;<\/span><\/span>\n        <\/span>}<\/span><\/span>\n    <\/span>}<\/span><\/span>\n<\/span>\n    <\/span>public<\/span> <\/span>static<\/span> Singleton <\/span>GetInstance<\/span>()<\/span><\/span>\n    <\/span>{<\/span><\/span>\n        <\/span>if<\/span> <\/span>(<\/span>__instance<\/span> <\/span>==<\/span> <\/span>null<\/span>)<\/span><\/span>\n        <\/span>{<\/span><\/span>\n            <\/span>__instance<\/span> <\/span>=<\/span> <\/span>new<\/span> Singleton<\/span>()<\/span>;<\/span><\/span>\n        <\/span>}<\/span><\/span>\n        <\/span>return<\/span> <\/span>__instance<\/span>;<\/span><\/span>\n    <\/span>}<\/span><\/span>\n}<\/span><\/span>\n<\/span>\n\/\/ Exemplo de uso:<\/span><\/span>\nSingleton s1 <\/span>=<\/span> <\/span>Singleton<\/span>.<\/span>GetInstance<\/span>()<\/span>;<\/span><\/span>\nSingleton s2 <\/span>=<\/span> <\/span>Singleton<\/span>.<\/span>GetInstance<\/span>()<\/span>;<\/span><\/span>\n<\/span>\nConsole<\/span>.<\/span>WriteLine<\/span>(<\/span>s1<\/span> <\/span>==<\/span> <\/span>s2<\/span>)<\/span>;<\/span> <\/span>\/\/ Output: True<\/span><\/span>\n<\/span>\n\/\/ Fonte: Chat GPT<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
Java<\/span><\/path><\/path><\/svg><\/span>
public<\/span> <\/span>class<\/span> <\/span>Singleton<\/span> <\/span>{<\/span><\/span>\n    <\/span>private<\/span> <\/span>static<\/span> <\/span>Singleton<\/span> <\/span>__instance<\/span> <\/span>=<\/span> <\/span>null;<\/span><\/span>\n<\/span>\n    <\/span>private<\/span> <\/span>Singleton<\/span>()<\/span> <\/span>{<\/span><\/span>\n        <\/span>if<\/span> <\/span>(<\/span>__instance <\/span>!=<\/span> <\/span>null<\/span>)<\/span> <\/span>{<\/span><\/span>\n            <\/span>throw<\/span> <\/span>new<\/span> <\/span>RuntimeException<\/span>(<\/span>"<\/span>Singleton cannot be instantiated more than once<\/span>"<\/span>)<\/span>;<\/span><\/span>\n        <\/span>}<\/span> <\/span>else<\/span> <\/span>{<\/span><\/span>\n            __instance <\/span>=<\/span> <\/span>this;<\/span><\/span>\n        <\/span>}<\/span><\/span>\n    <\/span>}<\/span><\/span>\n<\/span>\n    <\/span>public<\/span> <\/span>static<\/span> <\/span>Singleton<\/span> <\/span>getInstance<\/span>()<\/span> <\/span>{<\/span><\/span>\n        <\/span>if<\/span> <\/span>(<\/span>__instance <\/span>==<\/span> <\/span>null<\/span>)<\/span> <\/span>{<\/span><\/span>\n            __instance <\/span>=<\/span> <\/span>new<\/span> <\/span>Singleton<\/span>()<\/span>;<\/span><\/span>\n        <\/span>}<\/span><\/span>\n        <\/span>return<\/span> __instance<\/span>;<\/span><\/span>\n    <\/span>}<\/span><\/span>\n<\/span>\n    <\/span>public<\/span> <\/span>static<\/span> <\/span>void<\/span> <\/span>main<\/span>(<\/span>String<\/span>[]<\/span> <\/span>args<\/span>)<\/span> <\/span>{<\/span><\/span>\n        <\/span>Singleton<\/span> <\/span>s1<\/span> <\/span>=<\/span> <\/span>Singleton<\/span>.<\/span>getInstance<\/span>()<\/span>;<\/span><\/span>\n        <\/span>Singleton<\/span> <\/span>s2<\/span> <\/span>=<\/span> <\/span>Singleton<\/span>.<\/span>getInstance<\/span>()<\/span>;<\/span><\/span>\n<\/span>\n        <\/span>System<\/span>.<\/span>out<\/span>.<\/span>println<\/span>(<\/span>s1 <\/span>==<\/span> s2<\/span>)<\/span>;<\/span> <\/span>\/\/ Output: true<\/span><\/span>\n    <\/span>}<\/span><\/span>\n}<\/span><\/span>\n<\/span>\n\/\/ Fonte: Chat GPT<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
Python<\/span><\/path><\/path><\/svg><\/span>
class<\/span> <\/span>Singleton<\/span>:<\/span><\/span>\n    __instance <\/span>=<\/span> <\/span>None<\/span><\/span>\n<\/span>\n    <\/span>def<\/span> <\/span>__init__<\/span>(<\/span>self<\/span>):<\/span><\/span>\n        <\/span>if<\/span> Singleton<\/span>.<\/span>__instance <\/span>!=<\/span> <\/span>None<\/span>:<\/span><\/span>\n            <\/span>raise<\/span> <\/span>Exception<\/span>(<\/span>"<\/span>Singleton cannot be instantiated more than once<\/span>"<\/span>)<\/span><\/span>\n        <\/span>else<\/span>:<\/span><\/span>\n            Singleton<\/span>.<\/span>__instance <\/span>=<\/span> <\/span>self<\/span><\/span>\n<\/span>\n    <\/span>@<\/span>staticmethod<\/span><\/span>\n    <\/span>def<\/span> <\/span>getInstance<\/span>():<\/span><\/span>\n        <\/span>if<\/span> Singleton<\/span>.<\/span>__instance <\/span>==<\/span> <\/span>None<\/span>:<\/span><\/span>\n            <\/span>Singleton<\/span>()<\/span><\/span>\n        <\/span>return<\/span> Singleton<\/span>.<\/span>__instance<\/span><\/span>\n<\/span>\n# Exemplo de uso:<\/span><\/span>\ns1 <\/span>=<\/span> <\/span>Singleton<\/span>()<\/span><\/span>\ns2 <\/span>=<\/span> Singleton<\/span>.<\/span>getInstance<\/span>()<\/span><\/span>\n<\/span>\nprint<\/span>(<\/span>s1 <\/span>==<\/span> s2<\/span>)<\/span> <\/span># Output: True<\/span><\/span>\n<\/span>\n# Fonte: Chat GPT<\/span><\/span>\n<\/span><\/code><\/pre><\/div>\n\n\n\n
Factory Method<\/h2>\n\n\n\n
O Factory Method \u00e9 um Design Pattern que permite a cria\u00e7\u00e3o de objetos sem especificar sua classe exata. Isso \u00e9 \u00fatil para criar objetos de classes que podem variar em tempo de execu\u00e7\u00e3o. Veja exemplos de implementa\u00e7\u00e3o em C#, Java e Python:<\/p>\n\n\n\n
C#<\/span><\/path><\/path><\/svg><\/span>
using<\/span> System<\/span>;<\/span><\/span>\n<\/span>\npublic<\/span> <\/span>class<\/span> <\/span>Car<\/span><\/span>\n{<\/span><\/span>\n    <\/span>public<\/span> <\/span>virtual<\/span> <\/span>void<\/span> <\/span>Drive<\/span>()<\/span><\/span>\n    <\/span>{<\/span><\/span>\n        <\/span>\/\/ O m\u00e9todo pode ser vazio, j\u00e1 que \u00e9 sobrescrito pelas subclasses.<\/span><\/span>\n    <\/span>}<\/span><\/span>\n}<\/span><\/span>\n<\/span>\npublic<\/span> <\/span>class<\/span> <\/span>SportsCar<\/span> <\/span>:<\/span> Car<\/span><\/span>\n{<\/span><\/span>\n    <\/span>public<\/span> <\/span>override<\/span> <\/span>void<\/span> <\/span>Drive<\/span>()<\/span><\/span>\n    <\/span>{<\/span><\/span>\n        <\/span>Console<\/span>.<\/span>WriteLine<\/span>(<\/span>"<\/span>Driving a sports car<\/span>"<\/span>)<\/span>;<\/span><\/span>\n    <\/span>}<\/span><\/span>\n}<\/span><\/span>\n<\/span>\npublic<\/span> <\/span>class<\/span> <\/span>SUV<\/span> <\/span>:<\/span> Car<\/span><\/span>\n{<\/span><\/span>\n    <\/span>public<\/span> <\/span>override<\/span> <\/span>void<\/span> <\/span>Drive<\/span>()<\/span><\/span>\n    <\/span>{<\/span><\/span>\n        <\/span>Console<\/span>.<\/span>WriteLine<\/span>(<\/span>"<\/span>Driving an SUV<\/span>"<\/span>)<\/span>;<\/span><\/span>\n    <\/span>}<\/span><\/span>\n}<\/span><\/span>\n<\/span>\npublic<\/span> <\/span>class<\/span> <\/span>CarFactory<\/span><\/span>\n{<\/span><\/span>\n    <\/span>public<\/span> <\/span>static<\/span> Car <\/span>CreateCar<\/span>(<\/span>string<\/span> carType<\/span>)<\/span><\/span>\n    <\/span>{<\/span><\/span>\n        <\/span>switch<\/span> <\/span>(<\/span>carType<\/span>)<\/span><\/span>\n        <\/span>{<\/span><\/span>\n            <\/span>case<\/span> <\/span>"<\/span>SportsCar<\/span>"<\/span>:<\/span><\/span>\n                <\/span>return<\/span> <\/span>new<\/span> SportsCar<\/span>()<\/span>;<\/span><\/span>\n            <\/span>case<\/span> <\/span>"<\/span>SUV<\/span>"<\/span>:<\/span><\/span>\n                <\/span>return<\/span> <\/span>new<\/span> SUV<\/span>()<\/span>;<\/span><\/span>\n            <\/span>default<\/span>:<\/span><\/span>\n                <\/span>throw<\/span> <\/span>new<\/span> ArgumentException<\/span>(<\/span>"<\/span>Invalid car type<\/span>"<\/span>)<\/span>;<\/span><\/span>\n        <\/span>}<\/span><\/span>\n    <\/span>}<\/span><\/span>\n}<\/span><\/span>\n<\/span>\npublic<\/span> <\/span>class<\/span> <\/span>Program<\/span><\/span>\n{<\/span><\/span>\n    <\/span>public<\/span> <\/span>static<\/span> <\/span>void<\/span> <\/span>Main<\/span>()<\/span><\/span>\n    <\/span>{<\/span><\/span>\n        Car car1 <\/span>=<\/span> <\/span>CarFactory<\/span>.<\/span>CreateCar<\/span>(<\/span>"<\/span>SportsCar<\/span>"<\/span>)<\/span>;<\/span><\/span>\n        <\/span>car1<\/span>.<\/span>Drive<\/span>()<\/span>;<\/span> <\/span>\/\/ Output: Driving a sports car<\/span><\/span>\n<\/span>\n        Car car2 <\/span>=<\/span> <\/span>CarFactory<\/span>.<\/span>CreateCar<\/span>(<\/span>"<\/span>SUV<\/span>"<\/span>)<\/span>;<\/span><\/span>\n        <\/span>car2<\/span>.<\/span>Drive<\/span>()<\/span>;<\/span> <\/span>\/\/ Output: Driving an SUV<\/span><\/span>\n    <\/span>}<\/span><\/span>\n}<\/span><\/span>\n<\/span>\n\/\/ Fonte: Chat GPT<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
Java<\/span><\/path><\/path><\/svg><\/span>
public<\/span> <\/span>class<\/span> <\/span>Car<\/span> <\/span>{<\/span><\/span>\n    <\/span>public<\/span> <\/span>void<\/span> <\/span>drive<\/span>()<\/span> <\/span>{<\/span><\/span>\n        <\/span>\/\/ O m\u00e9todo pode ser vazio, j\u00e1 que \u00e9 sobrescrito pelas subclasses.<\/span><\/span>\n    <\/span>}<\/span><\/span>\n}<\/span><\/span>\n<\/span>\npublic<\/span> <\/span>class<\/span> <\/span>SportsCar<\/span> <\/span>extends<\/span> <\/span>Car<\/span> <\/span>{<\/span><\/span>\n    <\/span>public<\/span> <\/span>void<\/span> <\/span>drive<\/span>()<\/span> <\/span>{<\/span><\/span>\n        <\/span>System<\/span>.<\/span>out<\/span>.<\/span>println<\/span>(<\/span>"<\/span>Driving a sports car<\/span>"<\/span>)<\/span>;<\/span><\/span>\n    <\/span>}<\/span><\/span>\n}<\/span><\/span>\n<\/span>\npublic<\/span> <\/span>class<\/span> <\/span>SUV<\/span> <\/span>extends<\/span> <\/span>Car<\/span> <\/span>{<\/span><\/span>\n    <\/span>public<\/span> <\/span>void<\/span> <\/span>drive<\/span>()<\/span> <\/span>{<\/span><\/span>\n        <\/span>System<\/span>.<\/span>out<\/span>.<\/span>println<\/span>(<\/span>"<\/span>Driving an SUV<\/span>"<\/span>)<\/span>;<\/span><\/span>\n    <\/span>}<\/span><\/span>\n}<\/span><\/span>\n<\/span>\npublic<\/span> <\/span>class<\/span> <\/span>CarFactory<\/span> <\/span>{<\/span><\/span>\n    <\/span>public<\/span> <\/span>static<\/span> <\/span>Car<\/span> <\/span>createCar<\/span>(<\/span>String<\/span> <\/span>carType<\/span>)<\/span> <\/span>{<\/span><\/span>\n        <\/span>switch<\/span> <\/span>(<\/span>carType<\/span>)<\/span> <\/span>{<\/span><\/span>\n            <\/span>case<\/span> <\/span>"<\/span>SportsCar<\/span>"<\/span>:<\/span><\/span>\n                <\/span>return<\/span> <\/span>new<\/span> <\/span>SportsCar<\/span>()<\/span>;<\/span><\/span>\n            <\/span>case<\/span> <\/span>"<\/span>SUV<\/span>"<\/span>:<\/span><\/span>\n                <\/span>return<\/span> <\/span>new<\/span> <\/span>SUV<\/span>()<\/span>;<\/span><\/span>\n            <\/span>default:<\/span><\/span>\n                <\/span>throw<\/span> <\/span>new<\/span> <\/span>IllegalArgumentException<\/span>(<\/span>"<\/span>Invalid car type<\/span>"<\/span>)<\/span>;<\/span><\/span>\n        <\/span>}<\/span><\/span>\n    <\/span>}<\/span><\/span>\n}<\/span><\/span>\n<\/span>\npublic<\/span> <\/span>class<\/span> <\/span>Main<\/span> <\/span>{<\/span><\/span>\n    <\/span>public<\/span> <\/span>static<\/span> <\/span>void<\/span> <\/span>main<\/span>(<\/span>String<\/span>[]<\/span> <\/span>args<\/span>)<\/span> <\/span>{<\/span><\/span>\n        <\/span>Car<\/span> <\/span>car1<\/span> <\/span>=<\/span> <\/span>CarFactory<\/span>.<\/span>createCar<\/span>(<\/span>"<\/span>SportsCar<\/span>"<\/span>)<\/span>;<\/span><\/span>\n        <\/span>car1<\/span>.<\/span>drive<\/span>()<\/span>;<\/span> <\/span>\/\/ Output: Driving a sports car<\/span><\/span>\n<\/span>\n        <\/span>Car<\/span> <\/span>car2<\/span> <\/span>=<\/span> <\/span>CarFactory<\/span>.<\/span>createCar<\/span>(<\/span>"<\/span>SUV<\/span>"<\/span>)<\/span>;<\/span><\/span>\n        <\/span>car2<\/span>.<\/span>drive<\/span>()<\/span>;<\/span> <\/span>\/\/ Output: Driving an SUV<\/span><\/span>\n    <\/span>}<\/span><\/span>\n}<\/span><\/span>\n<\/span>\n\/\/ Fonte: Chat GPT<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
Python<\/span><\/path><\/path><\/svg><\/span>
class<\/span> <\/span>Car<\/span>:<\/span><\/span>\n    <\/span>def<\/span> <\/span>drive<\/span>(<\/span>self<\/span>):<\/span><\/span>\n        <\/span>pass<\/span><\/span>\n<\/span>\nclass<\/span> <\/span>SportsCar<\/span>(<\/span>Car<\/span>):<\/span><\/span>\n    <\/span>def<\/span> <\/span>drive<\/span>(<\/span>self<\/span>):<\/span><\/span>\n        <\/span>print<\/span>(<\/span>"<\/span>Driving a sports car<\/span>"<\/span>)<\/span><\/span>\n<\/span>\nclass<\/span> <\/span>SUV<\/span>(<\/span>Car<\/span>):<\/span><\/span>\n    <\/span>def<\/span> <\/span>drive<\/span>(<\/span>self<\/span>):<\/span><\/span>\n        <\/span>print<\/span>(<\/span>"<\/span>Driving an SUV<\/span>"<\/span>)<\/span><\/span>\n<\/span>\nclass<\/span> <\/span>CarFactory<\/span>:<\/span><\/span>\n    <\/span>@<\/span>staticmethod<\/span><\/span>\n    <\/span>def<\/span> <\/span>createCar<\/span>(<\/span>carType<\/span>):<\/span><\/span>\n        <\/span>if<\/span> carType <\/span>==<\/span> <\/span>"<\/span>SportsCar<\/span>"<\/span>:<\/span><\/span>\n            <\/span>return<\/span> <\/span>SportsCar<\/span>()<\/span><\/span>\n        <\/span>elif<\/span> carType <\/span>==<\/span> <\/span>"<\/span>SUV<\/span>"<\/span>:<\/span><\/span>\n            <\/span>return<\/span> <\/span>SUV<\/span>()<\/span><\/span>\n<\/span>\n# Exemplo de uso:<\/span><\/span>\ncar1 <\/span>=<\/span> CarFactory<\/span>.<\/span>createCar<\/span>(<\/span>"<\/span>SportsCar<\/span>"<\/span>)<\/span><\/span>\ncar1<\/span>.<\/span>drive<\/span>()<\/span> <\/span># Output: Driving a sports car<\/span><\/span>\n<\/span>\ncar2 <\/span>=<\/span> CarFactory<\/span>.<\/span>createCar<\/span>(<\/span>"<\/span>SUV<\/span>"<\/span>)<\/span><\/span>\ncar2<\/span>.<\/span>drive<\/span>()<\/span> <\/span># Output: Driving an SUV<\/span><\/span>\n<\/span>\n# Fonte: Chat GPT<\/span><\/span>\n<\/span><\/code><\/pre><\/div>\n\n\n\n
Observer<\/h2>\n\n\n\n
O Observer \u00e9 um Design Pattern que notifica objetos quando um evento ocorre. Isso \u00e9 \u00fatil para implementar eventos e comunica\u00e7\u00e3o entre objetos. Veja exemplos de implementa\u00e7\u00e3o em C#, Java e Python:<\/p>\n\n\n\n
C#<\/span><\/path><\/path><\/svg><\/span>
using<\/span> System<\/span>;<\/span><\/span>\nusing<\/span> System.Collections.Generic<\/span>;<\/span><\/span>\n<\/span>\nclass<\/span> <\/span>Subject<\/span><\/span>\n{<\/span><\/span>\n    <\/span>private<\/span> List<\/span><<\/span>Observer<\/span>><\/span> observers <\/span>=<\/span> <\/span>new<\/span> List<\/span><<\/span>Observer<\/span>>()<\/span>;<\/span><\/span>\n<\/span>\n    <\/span>public<\/span> <\/span>void<\/span> <\/span>AddObserver<\/span>(<\/span>Observer observer<\/span>)<\/span><\/span>\n    <\/span>{<\/span><\/span>\n        <\/span>observers<\/span>.<\/span>Add<\/span>(<\/span>observer<\/span>)<\/span>;<\/span><\/span>\n    <\/span>}<\/span><\/span>\n<\/span>\n    <\/span>public<\/span> <\/span>void<\/span> <\/span>RemoveObserver<\/span>(<\/span>Observer observer<\/span>)<\/span><\/span>\n    <\/span>{<\/span><\/span>\n        <\/span>observers<\/span>.<\/span>Remove<\/span>(<\/span>observer<\/span>)<\/span>;<\/span><\/span>\n    <\/span>}<\/span><\/span>\n<\/span>\n    <\/span>public<\/span> <\/span>void<\/span> <\/span>NotifyObservers<\/span>()<\/span><\/span>\n    <\/span>{<\/span><\/span>\n        <\/span>foreach<\/span> <\/span>(<\/span>Observer observer <\/span>in<\/span> <\/span>observers<\/span>)<\/span><\/span>\n        <\/span>{<\/span><\/span>\n            <\/span>observer<\/span>.<\/span>Update<\/span>()<\/span>;<\/span><\/span>\n        <\/span>}<\/span><\/span>\n    <\/span>}<\/span><\/span>\n}<\/span><\/span>\n<\/span>\nabstract<\/span> <\/span>class<\/span> <\/span>Observer<\/span><\/span>\n{<\/span><\/span>\n    <\/span>protected<\/span> Subject subject<\/span>;<\/span><\/span>\n<\/span>\n    <\/span>public<\/span> <\/span>Observer<\/span>(<\/span>Subject subject<\/span>)<\/span><\/span>\n    <\/span>{<\/span><\/span>\n        <\/span>this<\/span>.<\/span>subject<\/span> <\/span>=<\/span> <\/span>subject<\/span>;<\/span><\/span>\n        <\/span>subject<\/span>.<\/span>AddObserver<\/span>(<\/span>this<\/span>)<\/span>;<\/span><\/span>\n    <\/span>}<\/span><\/span>\n<\/span>\n    <\/span>public<\/span> <\/span>abstract<\/span> <\/span>void<\/span> <\/span>Update<\/span>()<\/span>;<\/span><\/span>\n}<\/span><\/span>\n<\/span>\nclass<\/span> <\/span>EmailNotifier<\/span> <\/span>:<\/span> Observer<\/span><\/span>\n{<\/span><\/span>\n    <\/span>public<\/span> <\/span>EmailNotifier<\/span>(<\/span>Subject subject<\/span>)<\/span> <\/span>:<\/span> <\/span>base<\/span>(<\/span>subject<\/span>)<\/span><\/span>\n    <\/span>{<\/span><\/span>\n    <\/span>}<\/span><\/span>\n<\/span>\n    <\/span>public<\/span> <\/span>override<\/span> <\/span>void<\/span> <\/span>Update<\/span>()<\/span><\/span>\n    <\/span>{<\/span><\/span>\n        <\/span>Console<\/span>.<\/span>WriteLine<\/span>(<\/span>"<\/span>Sending email notification<\/span>"<\/span>)<\/span>;<\/span><\/span>\n    <\/span>}<\/span><\/span>\n}<\/span><\/span>\n<\/span>\nclass<\/span> <\/span>SMSNotifier<\/span> <\/span>:<\/span> Observer<\/span><\/span>\n{<\/span><\/span>\n    <\/span>public<\/span> <\/span>SMSNotifier<\/span>(<\/span>Subject subject<\/span>)<\/span> <\/span>:<\/span> <\/span>base<\/span>(<\/span>subject<\/span>)<\/span><\/span>\n    <\/span>{<\/span><\/span>\n    <\/span>}<\/span><\/span>\n<\/span>\n    <\/span>public<\/span> <\/span>override<\/span> <\/span>void<\/span> <\/span>Update<\/span>()<\/span><\/span>\n    <\/span>{<\/span><\/span>\n        <\/span>Console<\/span>.<\/span>WriteLine<\/span>(<\/span>"<\/span>Sending SMS notification<\/span>"<\/span>)<\/span>;<\/span><\/span>\n    <\/span>}<\/span><\/span>\n}<\/span><\/span>\n<\/span>\n\/\/ Exemplo de uso:<\/span><\/span>\nSubject subject <\/span>=<\/span> <\/span>new<\/span> Subject<\/span>()<\/span>;<\/span><\/span>\nEmailNotifier emailNotifier <\/span>=<\/span> <\/span>new<\/span> EmailNotifier<\/span>(<\/span>subject<\/span>)<\/span>;<\/span><\/span>\nSMSNotifier smsNotifier <\/span>=<\/span> <\/span>new<\/span> SMSNotifier<\/span>(<\/span>subject<\/span>)<\/span>;<\/span><\/span>\n<\/span>\nsubject<\/span>.<\/span>NotifyObservers<\/span>()<\/span>;<\/span> <\/span>\/\/ Output: Sending email notification, Sending SMS notification<\/span><\/span>\n<\/span>\n\/\/ Fonte: Chat GPT<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
Java<\/span><\/path><\/path><\/svg><\/span>
import<\/span> <\/span>java<\/span>.<\/span>util<\/span>.<\/span>ArrayList<\/span>;<\/span><\/span>\nimport<\/span> <\/span>java<\/span>.<\/span>util<\/span>.<\/span>List<\/span>;<\/span><\/span>\n<\/span>\npublic<\/span> <\/span>class<\/span> <\/span>Subject<\/span> <\/span>{<\/span><\/span>\n    <\/span>private<\/span> <\/span>List<\/span><<\/span>Observer<\/span>><\/span> <\/span>observers<\/span> <\/span>=<\/span> <\/span>new<\/span> <\/span>ArrayList<\/span><<\/span>Observer<\/span>>()<\/span>;<\/span><\/span>\n<\/span>\n    <\/span>public<\/span> <\/span>void<\/span> <\/span>addObserver<\/span>(<\/span>Observer<\/span> <\/span>observer<\/span>)<\/span> <\/span>{<\/span><\/span>\n        <\/span>observers<\/span>.<\/span>add<\/span>(<\/span>observer<\/span>)<\/span>;<\/span><\/span>\n    <\/span>}<\/span><\/span>\n<\/span>\n    <\/span>public<\/span> <\/span>void<\/span> <\/span>removeObserver<\/span>(<\/span>Observer<\/span> <\/span>observer<\/span>)<\/span> <\/span>{<\/span><\/span>\n        <\/span>observers<\/span>.<\/span>remove<\/span>(<\/span>observer<\/span>)<\/span>;<\/span><\/span>\n    <\/span>}<\/span><\/span>\n<\/span>\n    <\/span>public<\/span> <\/span>void<\/span> <\/span>notifyObservers<\/span>()<\/span> <\/span>{<\/span><\/span>\n        <\/span>for<\/span> <\/span>(<\/span>Observer<\/span> <\/span>observer<\/span> <\/span>:<\/span> observers<\/span>)<\/span> <\/span>{<\/span><\/span>\n            <\/span>observer<\/span>.<\/span>update<\/span>()<\/span>;<\/span><\/span>\n        <\/span>}<\/span><\/span>\n    <\/span>}<\/span><\/span>\n}<\/span><\/span>\n<\/span>\nabstract<\/span> <\/span>class<\/span> <\/span>Observer<\/span> <\/span>{<\/span><\/span>\n    <\/span>protected<\/span> <\/span>Subject<\/span> <\/span>subject<\/span>;<\/span><\/span>\n<\/span>\n    <\/span>public<\/span> <\/span>Observer<\/span>(<\/span>Subject<\/span> <\/span>subject<\/span>)<\/span> <\/span>{<\/span><\/span>\n        <\/span>this<\/span>.<\/span>subject<\/span> <\/span>=<\/span> subject<\/span>;<\/span><\/span>\n        <\/span>subject<\/span>.<\/span>addObserver<\/span>(<\/span>this<\/span>)<\/span>;<\/span><\/span>\n    <\/span>}<\/span><\/span>\n<\/span>\n    <\/span>public<\/span> <\/span>abstract<\/span> <\/span>void<\/span> <\/span>update<\/span>()<\/span>;<\/span><\/span>\n}<\/span><\/span>\n<\/span>\nclass<\/span> <\/span>EmailNotifier<\/span> <\/span>extends<\/span> <\/span>Observer<\/span> <\/span>{<\/span><\/span>\n    <\/span>public<\/span> <\/span>EmailNotifier<\/span>(<\/span>Subject<\/span> <\/span>subject<\/span>)<\/span> <\/span>{<\/span><\/span>\n        <\/span>super<\/span>(<\/span>subject<\/span>)<\/span>;<\/span><\/span>\n    <\/span>}<\/span><\/span>\n<\/span>\n    <\/span>public<\/span> <\/span>void<\/span> <\/span>update<\/span>()<\/span> <\/span>{<\/span><\/span>\n        <\/span>System<\/span>.<\/span>out<\/span>.<\/span>println<\/span>(<\/span>"<\/span>Sending email notification<\/span>"<\/span>)<\/span>;<\/span><\/span>\n    <\/span>}<\/span><\/span>\n}<\/span><\/span>\n<\/span>\nclass<\/span> <\/span>SMSNotifier<\/span> <\/span>extends<\/span> <\/span>Observer<\/span> <\/span>{<\/span><\/span>\n    <\/span>public<\/span> <\/span>SMSNotifier<\/span>(<\/span>Subject<\/span> <\/span>subject<\/span>)<\/span> <\/span>{<\/span><\/span>\n        <\/span>super<\/span>(<\/span>subject<\/span>)<\/span>;<\/span><\/span>\n    <\/span>}<\/span><\/span>\n<\/span>\n    <\/span>public<\/span> <\/span>void<\/span> <\/span>update<\/span>()<\/span> <\/span>{<\/span><\/span>\n        <\/span>System<\/span>.<\/span>out<\/span>.<\/span>println<\/span>(<\/span>"<\/span>Sending SMS notification<\/span>"<\/span>)<\/span>;<\/span><\/span>\n    <\/span>}<\/span><\/span>\n}<\/span><\/span>\n<\/span>\n\/\/ Exemplo de uso:<\/span><\/span>\nSubject<\/span> <\/span>subject<\/span> <\/span>=<\/span> <\/span>new<\/span> <\/span>Subject<\/span>()<\/span>;<\/span><\/span>\nEmailNotifier<\/span> <\/span>emailNotifier<\/span> <\/span>=<\/span> <\/span>new<\/span> <\/span>EmailNotifier<\/span>(<\/span>subject<\/span>)<\/span>;<\/span><\/span>\nSMSNotifier<\/span> <\/span>smsNotifier<\/span> <\/span>=<\/span> <\/span>new<\/span> <\/span>SMSNotifier<\/span>(<\/span>subject<\/span>)<\/span>;<\/span><\/span>\n<\/span>\nsubject<\/span>.<\/span>notifyObservers<\/span>()<\/span>;<\/span> <\/span>\/\/ Output: Sending email notification, Sending SMS notification<\/span><\/span>\n<\/span>\n\/\/ Fonte: Chat GPT<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
Python<\/span><\/path><\/path><\/svg><\/span>
class<\/span> <\/span>Subject<\/span>:<\/span><\/span>\n    <\/span>def<\/span> <\/span>__init__<\/span>(<\/span>self<\/span>):<\/span><\/span>\n        <\/span>self<\/span>.<\/span>__observers <\/span>=<\/span> <\/span>[]<\/span><\/span>\n<\/span>\n    <\/span>def<\/span> <\/span>addObserver<\/span>(<\/span>self<\/span>,<\/span> <\/span>observer<\/span>):<\/span><\/span>\n        <\/span>self<\/span>.<\/span>__observers<\/span>.<\/span>append<\/span>(<\/span>observer<\/span>)<\/span><\/span>\n<\/span>\n    <\/span>def<\/span> <\/span>removeObserver<\/span>(<\/span>self<\/span>,<\/span> <\/span>observer<\/span>):<\/span><\/span>\n        <\/span>self<\/span>.<\/span>__observers<\/span>.<\/span>remove<\/span>(<\/span>observer<\/span>)<\/span><\/span>\n<\/span>\n    <\/span>def<\/span> <\/span>notifyObservers<\/span>(<\/span>self<\/span>):<\/span><\/span>\n        <\/span>for<\/span> observer <\/span>in<\/span> <\/span>self<\/span>.<\/span>__observers<\/span>:<\/span><\/span>\n            observer<\/span>.<\/span>update<\/span>()<\/span><\/span>\n<\/span>\nclass<\/span> <\/span>Observer<\/span>:<\/span><\/span>\n    <\/span>def<\/span> <\/span>__init__<\/span>(<\/span>self<\/span>,<\/span> <\/span>subject<\/span>):<\/span><\/span>\n        <\/span>self<\/span>.<\/span>subject <\/span>=<\/span> subject<\/span><\/span>\n        <\/span>self<\/span>.<\/span>subject<\/span>.<\/span>addObserver<\/span>(<\/span>self<\/span>)<\/span><\/span>\n<\/span>\n    <\/span>def<\/span> <\/span>update<\/span>(<\/span>self<\/span>):<\/span><\/span>\n        <\/span>pass<\/span><\/span>\n<\/span>\nclass<\/span> <\/span>EmailNotifier<\/span>(<\/span>Observer<\/span>):<\/span><\/span>\n    <\/span>def<\/span> <\/span>update<\/span>(<\/span>self<\/span>):<\/span><\/span>\n        <\/span>print<\/span>(<\/span>"<\/span>Sending email notification<\/span>"<\/span>)<\/span><\/span>\n<\/span>\nclass<\/span> <\/span>SMSNotifier<\/span>(<\/span>Observer<\/span>):<\/span><\/span>\n    <\/span>def<\/span> <\/span>update<\/span>(<\/span>self<\/span>):<\/span><\/span>\n        <\/span>print<\/span>(<\/span>"<\/span>Sending SMS notification<\/span>"<\/span>)<\/span><\/span>\n<\/span>\n# Exemplo de uso:<\/span><\/span>\nsubject <\/span>=<\/span> <\/span>Subject<\/span>()<\/span><\/span>\nemailNotifier <\/span>=<\/span> <\/span>EmailNotifier<\/span>(<\/span>subject<\/span>)<\/span><\/span>\nsmsNotifier <\/span>=<\/span> <\/span>SMSNotifier<\/span>(<\/span>subject<\/span>)<\/span><\/span>\n<\/span>\nsubject<\/span>.<\/span>notifyObservers<\/span>()<\/span> <\/span># Output: Sending email notification, Sending SMS notification<\/span><\/span>\n<\/span>\n# Fonte: Chat GPT<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
A import\u00e2ncia da avalia\u00e7\u00e3o e adaptabilidade ao utilizar Design Patterns em projetos de software<\/h2>\n\n\n\n
Ao utilizar Design Patterns, os desenvolvedores podem aproveitar solu\u00e7\u00f5es comprovadas e testadas em vez de reinventar a roda a cada novo projeto. Isso pode economizar tempo e reduzir o risco de erros de programa\u00e7\u00e3o. Al\u00e9m disso, o uso consistente de Design Patterns pode melhorar a legibilidade do c\u00f3digo e facilitar a manuten\u00e7\u00e3o do software ao longo do tempo.<\/p>\n\n\n\n
No entanto, \u00e9 importante lembrar que os Design Patterns n\u00e3o s\u00e3o uma solu\u00e7\u00e3o para todos os problemas de programa\u00e7\u00e3o. \u00c9 preciso avaliar cuidadosamente se um Design Pattern \u00e9 apropriado para o problema em quest\u00e3o. Alguns problemas podem ter solu\u00e7\u00f5es mais simples ou espec\u00edficas para a situa\u00e7\u00e3o.<\/p>\n\n\n\n
Al\u00e9m disso, \u00e9 importante lembrar que os Design Patterns n\u00e3o devem ser seguidos cegamente. Cada projeto \u00e9 \u00fanico e pode ter necessidades espec\u00edficas. Os Design Patterns devem ser usados como um guia, mas a adaptabilidade \u00e9 fundamental para criar solu\u00e7\u00f5es personalizadas e eficientes.<\/p>\n\n\n\n
<\/p>\n\n\n\n
Conclus\u00e3o<\/h2>\n\n\n\n
Em resumo, os Design Patterns s\u00e3o uma abordagem comprovada para a cria\u00e7\u00e3o de solu\u00e7\u00f5es eficientes e reutiliz\u00e1veis para problemas comuns de programa\u00e7\u00e3o. Eles podem economizar tempo, reduzir erros de programa\u00e7\u00e3o e melhorar a manuten\u00e7\u00e3o do software ao longo do tempo. No entanto, \u00e9 importante avaliar cuidadosamente se um Design Pattern \u00e9 apropriado para o problema em quest\u00e3o e adapt\u00e1-lo \u00e0s necessidades espec\u00edficas do projeto.<\/p>\n\n\n\n
Esse conte\u00fado \u00e9 parte do material disponibilizado para os participantes do meu grupo de estudos de Padr\u00f5es de Projeto<\/strong>. Voc\u00ea quer participar desse grupo? Clique aqui e veja como funciona<\/a><\/strong>.<\/p>\n","protected":false},"featured_media":4155,"parent":0,"template":"","cursos":[7],"class_list":["post-4154","artigos","type-artigos","status-publish","has-post-thumbnail","hentry","cursos-gof"],"acf":[],"_links":{"self":[{"href":"https:\/\/elemarjr.com\/clube-de-estudos\/wp-json\/wp\/v2\/artigos\/4154","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/elemarjr.com\/clube-de-estudos\/wp-json\/wp\/v2\/artigos"}],"about":[{"href":"https:\/\/elemarjr.com\/clube-de-estudos\/wp-json\/wp\/v2\/types\/artigos"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/elemarjr.com\/clube-de-estudos\/wp-json\/wp\/v2\/media\/4155"}],"wp:attachment":[{"href":"https:\/\/elemarjr.com\/clube-de-estudos\/wp-json\/wp\/v2\/media?parent=4154"}],"wp:term":[{"taxonomy":"cursos","embeddable":true,"href":"https:\/\/elemarjr.com\/clube-de-estudos\/wp-json\/wp\/v2\/cursos?post=4154"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}