Strategy Design pattern: Behavioral patterns

Share the Article

What

Strategy Design pattern is a type of behavior pattern. This pattern is mainly used for an application which needs to support families of algorithm. Basically, it enables a client to consume an application with many algorithms very easily.

It create hierarchy of algorithms and embeds them inside a strategy class. After that the client shall interact with only with strategy class. Due to separate hierarchy for algorithms, if more algorithm get added or existing get updated, it will not impact client.

In summary, an application using strategy design pattern is very easy to adapt to support new algorithms.

Why

Let us try to understand the need of strategy design pattern by taking an application whose job is to play video on computer screen.

Application need to take care of different video formats in order to play videos on computer.

Below are the some samples of video formats which the application may support:

  • MP4
  • AVI
  • HD video
  • Ultra HD video

Generally, the video formats mainly differs on video input video stream encoding mechanism. However, a specific video stream encoding again depends on video height and width. For selecting any video format need to give input for height and width also.

Sample application without Startegy design pattern

Below is the sample application without using Strategy design pattern. Here, we have abstract class VideoFormat with which the client is directly interacting.

#include<iostream> //main header using namespace std;//for namespace class VideoFormat { public: virtual void playVideo()=0; }; class AVI: public VideoFormat { public: AVI( string encodingFormat, int height, int weight) { } void playVideo() { cout<<" AVI format video playing"<<endl; } }; class HD: public VideoFormat { public: HD(string encodingFormat, int width) { } void playVideo() { cout<<" HD format video playing"<<endl; } }; int main() { AVI a1("AVI encoding", 700, 780); a1.playVideo(); HD h1("HD encoding",1200); h1.playVideo(); return 0; }

As seen above, the client is directly interacting with 2 video formats. Therefore, the client need to understand the video formats and need to select properties as given below also:

  • Encoding mechanism “AVI encoding” or “HD encoding”
  • height or width

Hence, with above approach, the client needs to keep adapting if newer video algorithms are added. Finally, the client and algorithm remain directly linked to each other.

In order to solve above problem we need a design pattern which creates loose coupling between client and class video format.

How

In order to solve above problem with Strategy pattern we need to follow below rules:

Strategy Wrapper Class

Firstly, create a Strategy wrapper class which shall hold pointer to video format class.

Below is code snippet of the new Strategy wrapper class

class StrategyVideo { private: VideoFormat *m_f1; };

Expose interface to set strategy

The strategy class shall expose interface for client to select strategy. Therefore, this will let strategy class to handle all complexity of the video algorithm, such as height, width, encoding format, etc.

class StrategyVideo { private: StrategyVideo *m_f1; public: void setStrategyVideo( Video_Type vtype) { } };

Updated application using Strategy design pattern

#include<iostream> //main header using namespace std;//for namespace class VideoFormat { public: virtual void playVideo()=0; }; class AVI:public VideoFormat { public: AVI(string encodingFormat, int height, int weight) { } void playVideo() { cout<<" AVI format video playing"<<endl; } }; class HD: public VideoFormat { public: HD( string encodingformat, int width) { } void playVideo() { cout<<" HD format video playing"<<endl; } }; enum Video_type { AVI_VIDEO, HD_VIDEO }; class StrategyVideo { VideoFormat *m_vf; public: void setStrategyVideo(Video_type vtype) { switch(vtype) { case AVI_VIDEO: m_vf = new AVI("AVI",700,780); break; case HD_VIDEO: m_vf = new HD("HD",1200); break; } } void playVideo() { m_vf->playVideo(); } ~StrategyVideo() { delete m_vf; } }; int main() { StrategyVideo SV1; SV1.setStrategyVideo(AVI_VIDEO); SV1.playVideo(); StrategyVideo SV2; SV2.setStrategyVideo(HD_VIDEO); SV2.playVideo(); return 0; }

As seen above, with Strategy design pattern, now the algorithms and client are independent. It is very easy to introduce new algorithms and update existing also. There is no tight coupling between user and application.

Pros and Cons for Strategy design pattern

Pros

  • Firstly, it becomes is easy for application to introduce algorithms dynamically.
  • Moreover, the client do not directly depend on algorithms.

Cons

  • Design is not easy due to introduction of new class.

Main Funda: Strategy design patterns enables a class to change the algorithm at run-time.

Advanced C++ Topics

Abstract Factory Design Pattern
Singleton Design Pattern
Factory Method Design Pattern
Builder Design Pattern
Adapter Design Pattern
Prototype Design Pattern
Facade Design Pattern
Bridge Design Pattern
Composite Design Pattern
Decorator Design Pattern
Template Design Pattern

Share the Article

3,390 thoughts on “Strategy Design pattern: Behavioral patterns

  1. We picked out five features that lured us in. If you’re feeling particularly daring, Urban Decay’s Heavy Metal collection is definitely worth exploring. The jewel-toned glitter liners have the same staying power as the brand’s classic liquid liners and the sparkling formula doesn’t drop, so you don’t have to worry about it smudging down your face. SHOP NOW The price of your liquid glitter eyeliner will be determined by its size and quality, as well as the brand name behind it. Cheaper models may not be worth buying due to poor construction and durability issues, while more expensive ones may only be worth it if they offer something special. Do you want to buy a cheap liquid glitter eyeliner or an expensive one? The answer depends on how much you are willing to spend on it. The more expensive ones will have more features and better quality, but they also cost more. If you are on a budget, then go for the cheaper ones but still make sure that they meet your requirements. You can also consider buying refurbished or used products if you want to save money but don’t compromise on quality. https://miuces.com/foro/profile/lylec3555221692/ i == 1 ? ” : ‘hide’).join(”)” =”}’).split(‘,’).map((x,i) => i == 1 ? x : ”).join(”)”> Return accepted within 30 days with original packaging. Learn more > Available In-store and Online! PORTABLE: The soft rubber handle makes the carrying more comfortable and convenient. The built-in 1500mAh lithium battery in the mirror ensures long-term use. Some people simply can’t travel without a new pair of sunglasses for every outfit, and they’re unfortunately one of those items that break or get lost *super* easily. Help them out with this super chic sunglasses box case that easily unfolds and hangs on the back of a door for safe organization. ✈️ FREE UK DELIVERY – 14 Day Easy Returns – International Shipping MUID combines a cosmetic case with a vanity mirror. It not only can store cosmetics for you but also the LED mirror can come in handy when you need makeup.

  2. On its second run, many people finally took the dive and started to get interested.Previsao do Bitcoin para Janeiro de 2024.Dependendo do aplicativo, mais informacoes podem ser exigidas pelo aplicativo, como um numero de celular e um endereco de e-mail. https://www.alifba.co.uk/forum/english-forum/spin-samurai-deposito-brazil Spin Samurai depГіsito Brazil Evita o deslizamento do tubo e pode ser ajustado ate 12” Compartimento para ferramentas.Big blocks on Bitcoin SV facilitate lower average transaction fees which enable micropayments.The proliferation of crypto casinos will provide gamblers with more choice than they’ve ever had.Google, Twitter and Facebook all passed bans on Bitcoin and cryptocurrency advertisements on their platforms, with the latter claiming that they were “frequently associated with misleading or deceptive promotional practices.Accepts various prominent cryptocurrencies Easy sign-up process Up to 25% cash back on the first deposit Does not require wagering Fast and efficient customer support Protects users from fraud and data abuse with SSL encryption.Later, in May, the coin fell to $101.Locacao de Maquina de Ranhura.Ethereum is meant to be a decentralized world computer.Primeiramente, a vantagem principal se trata da isencao de impostos e taxas.

  3. Alongside the wide collection of online casinos, there is a wide collection of gambling software providers who create and maintain the games that we know and love.A nice, firm, sandy squeeze that lingers so long it becomes awkward.Game, que pode ser considerado o melhor cassino Ethereum, alem disso, ele suporta e fornece mais de 110 criptomoedas, isso inclui a mais famosa criptomoeda, o BTC, mas nao e limitado a Bitcoin, Ethereum e outras altcoins. https://www.everylifeonpurpose.com/forum/welcome-to-the-forum/histakes-metodos-de-deposito-brasil Histakes métodos de depósito Brasil And because Mercedes Classic has all the replacement parts you need, it’s less daunting to actually drive it.These games are supplied by 35 unique software providers, ensuring that gamblers have access to the latest and greatest innovations within the industry.No entanto, um corretor permite que os usuarios negociem a volatilidade do preco do Bitcoin por meio de CFDs.As primeiras trocas de Bitcoin eram plataformas simples de ponto a ponto que permitiam que compradores e vendedores se conectassem para negociar Bitcoin transferindo fiat uns para os outros.Over two hundred different slots are available at Bovada.Other than slots, 7bit also features a good selection of table games like blackjack, roulette, and baccarat, as well as video poker, lottery-style games, and more.Bitstarz is a trusted Bitcoin casino that’s received several awards since its launch in 2014.Porem, Runets se recusou a contar mais detalhes sobre o fabricante, os modelos dos equipamentos e sobre quem e o destinatario.Cloudbet is the largest and most well-known digital casino in the UK with more than five thousand slots and live gambling games.

  4. Os usuarios tambem podem escolher um programa de fidelidade que da a oportunidade de receber reembolso e bonus de recarga.The adaptation of Bitcoin is also progressing further, so that more and more companies are offering the option of paying for goods and services with Bitcoin.Click the button or the link inside the message. https://www.limitededitionsonly.com/forum/fashion-forum/betsson-espelho-brasil Betsson espelho Brasil We list the Top Bitcoin Sports Betting Sites.With certain variations, BTC managed to be in the range of $0.O sistema permite um alto nivel de anonimato, impedindo que instituicoes verifiquem seus envios ou recebimentos.BetOnline has been listed #4 on Casino Advisor’s Top 10 casino sites for safety for 2018.Basta enviar a inscricao e aguardar que o departamento de conformidade da CEX.A ranhuradora de cilindros hidraulicos Modelo YG12D, alimentada por um motor de inducao de 1100 W,.Gamblers have the option to deposit using seven different cryptocurrencies, including Bitcoin Cash, Dogecoin, and Tether.Game) como bonus que pode ser usado para jogar mais jogos.De acordo com a TradeBlock, fornecedora de dados de criptomoedas e ferramentas de negociacao para moedas digitais, a taxa de hash (hash rate) do Bitcoin atingiu, em uma media de 7 dias, 123,4 exahashes por segundo (E/Hs) em 7 de julho, superando o topo de marco.

  5. The headquarters are in Malta, which is becoming increasingly popular for online gaming companies.The loyalty program features several VIP levels you can climb to grab special rewards almost every day.Up to ?600 Bitcoin Bonus. https://www.theuground.com/forum/community-content/maquina-de-ranhura-bitcoin-na-india MГЎquina de ranhura bitcoin na Г­ndia Before you start playing at all, you should have a budget in mind.Whether or not a casino accepts cryptocurrencies has nothing to do with how legitimate it is and there are plenty of shady fiat casinos in operation.Uma simples troca P2P pode ser uma opcao melhor se os graficos complexos e os livros de pedidos o sobrecarregarem.Which pushes it head-on against the flaws of FIAT.The minimum amount of money you must deposit, however, is limited.Bitcoin Cash is a derivative of BTC.A ranhuradora de cilindros hidraulicos Modelo YG12D, alimentada por um motor de inducao de 1100 W,.Paises restritos: EUA, Reino Unido, Espanha, Israel, Franca, Holanda.Game – Nossa escolha para o melhor cassino de Bitcoin dos EUA 2.

  6. O que sao os pools de mineracao e como posso me juntar a eles?As apostas sao colocadas numa mesa com os numeros correspondentes aos numeros da roda.Se voce ganhar 9 bolas de ouro e preencher todos os slots de ouro, onde voce encontrara ofertas de cassinos online respeitaveis. https://www.rayshaco.co.uk/forum/fashion-forum/bodog-cassino-100-giros-livres-brasil Bodog Cassino 100 giros livres Brasil In addition, the technology offers unparalleled levels of security and protection.Slots 3D : As slots 3D oferecem uma experiencia VIP ao jogador.Each Bitcoin wallet has an associated private key.Having a high-quality gaming lobby is unquestionably the most important factor to consider when selecting an online gambling site.Os jogos comuns nesses cassinos incluem: Slots, incluindo slots classicas, video slots, slots de jackpot e tambem ofertas de slots especiais como as slots da Marvel e de Hollywood Jogos de mesa como blackjack, roleta, bacara e mais Jogos com dealers ao vivo como blackjack ao vivo, roleta ao vivo, bacara ao vivo, Sic Bo ao vivo, Hold’em ao vivo e outros Videopoquer e jogos especiais, embora estes estejam disponiveis em apenas alguns desses cassinos.The average hash rate for the average miner is approximately around 100kh/s.If you have not previously done so, the next step is to find your Bitcoin Wallet site.Bitcoin All Time High in GBP.A few months later, in June, the price of one Bitcoin hit $10, then $30 on Mt.

  7. Montelukast trade names Singulair, Montelo 10, and Monteflo and Lukotas in India is a leukotriene receptor antagonist LTRA used for the maintenance treatment of asthma and to relieve symptoms of seasonal allergies clomid success stories 5 mg cap reviews JINAN, China Гў A Chinese court convicted Bo Xilai of corruption Sunday and gave him a stern sentence of life in prison, capping a 20 month scandal that derailed one of ChinaГў s most up and coming politicians while exposing a murder and illicit enrichment among the countryГў s elite

  8. The next time I read a blog, I hope that it doesn’t fail me as much as this particular one. After all, Yes, it was my choice to read, nonetheless I genuinely believed you would have something helpful to say. All I hear is a bunch of whining about something you could possibly fix if you weren’t too busy searching for attention.

  9. In a small substudy N 81 of the NSABP P 1 trial, there appeared to be no benefit to screening women for Factor V Leiden and Prothrombin mutations G20210A as a means to identify those who may not be appropriate candidates for Tamoxifen Citrate Actavis tamoxifen citrate therapy 5 mg cialis generic india

  10. Francis publicou um vídeo em seu Twitter em agradecimento à comissão da cidade pela aprovação da resolução. Fonte: Jornal Extra* O estratagema está montado no Facebook, não sei se noutras redes sociais também. Mas no Facebook aparece como artigo patrocinado. Ou seja, o Facebook ganha dinheiro com isto sem acautelar o conteúdo da história. Se fosse uma fotografia do quadro “La Belle Romaine” de Modigliani ou até mesmo da escultura Vênus de Willendorf (de autor desconhecido), lá vinha o algoritmo censório e o bloqueio por 30 dias ou mais. Mas se for apenas o bom nome de um cidadão, isso já não importa, desde que o abusador pague pela publicidade maldosa e enganadora. Após decisão em benefício do Habeas Corpus de Glaidson Acácio dos Santos, conhecido como o “Faraó do Bitcoin”, dois dos líderes da GAS Consultoria foram soltos. As informações estão no portal de notícias O Globo. https://forum1.cafh.us/cafhcafe/forum/profile/natishabrummitt/ Um investimento pressupõe, além do ganho de capital com a valorização do ativo, o recebimento de juros, dividendos ou bonificações. Com criptomoedas você não tem esse tipo de ganho. Conforme o informado pelo Mercado Livre, de início, o que será permitido em sua plataforma cripto é: comprar, vender e manter uma reserva de criptomoedas. Já Escudero pontua que, como meio de pagamento, o mercado adotou o bitcoin como padrão pelo fato de ele servir como facilitador para remessas de grandes valores. “Em menos de 10 ou 20 minutos, você pode transferir US$ 100 milhões para o outro lado do mundo, pagando uma taxa menor do que um cafezinho”, diz o especialista em criptomoedas. Uma outra forma de criar uma carteira de criptomoedas é através do Blockchain diretamente. Essa é considerada também como uma carteira oficial sendo bastante segura, com atualizações e manutenções regulares. Acessando o site é possível cadastrar um perfil e já ter acesso aos Bitcoins facilmente. Esse é um método mais fácil para quem está começando, mas vale ressaltar que não dá para comprar ou para vender, mas somente realizar transações de envio e de recebimento de moedas.

  11. In turn, a few studies have found adverse outcomes in relation to CHM, including gastrointestinal reactions, preterm birth, premature rupture of membranes, stillbirth, asphyxia, and infections that cause neonatal death 27 priligy canada It s concerning if you do a perfect prostatectomy but the patient isn t likely to benefit from it

  12. I have been looking for articles on these topics for a long time. bitcoincasino I don’t know how grateful you are for posting on this topic. Thank you for the numerous articles on this site, I will subscribe to those links in my bookmarks and visit them often. Have a nice day

  13. An outstanding share! I’ve just forwarded this onto a coworker who had been conducting a little research on this. And he in fact bought me dinner because I found it for him… lol. So allow me to reword this…. Thank YOU for the meal!! But yeah, thanx for spending time to discuss this issue here on your web page.

  14. I believe that avoiding refined foods would be the first step so that you can lose weight. They may taste good, but refined foods possess very little vitamins and minerals, making you take in more just to have enough electricity to get over the day. For anyone who is constantly consuming these foods, transitioning to cereals and other complex carbohydrates will aid you to have more vitality while consuming less. Great blog post.

  15. Can I simply say what a comfort to uncover someone who truly understands what they are talking about on the net. You certainly know how to bring a problem to light and make it important. A lot more people must check this out and understand this side of the story. I can’t believe you aren’t more popular given that you most certainly possess the gift.

  16. Having read this I believed it was very informative. I appreciate you taking the time and effort to put this short article together. I once again find myself spending a significant amount of time both reading and leaving comments. But so what, it was still worthwhile.

  17. Hi there! I could have sworn I’ve been to this blog before but after looking at a few of the articles I realized it’s new to me. Regardless, I’m definitely pleased I came across it and I’ll be bookmarking it and checking back regularly!

  18. Aw, this was an extremely nice post. Finding the time and actual effort to generate a top notch article… but what can I say… I put things off a lot and don’t manage to get anything done.

  19. This is really interesting, You’re a very skilled blogger. I’ve joined your feed and look forward to seeking more of your magnificent post. Also, I’ve shared your site in my social networks!