Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-09-04T20:48:36Z No. of bitstreams: 1 AdorilsonBezerraDeAraujo_DISSERT.pdf: 1520413 bytes, checksum: c9a4bb003f34cd8b94eb21679d5d37e0 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-09-06T20:51:39Z (GMT) No. of bitstreams: 1 AdorilsonBezerraDeAraujo_DISSERT.pdf: 1520413 bytes, checksum: c9a4bb003f34cd8b94eb21679d5d37e0 (MD5) / Made available in DSpace on 2017-09-06T20:51:39Z (GMT). No. of bitstreams: 1 AdorilsonBezerraDeAraujo_DISSERT.pdf: 1520413 bytes, checksum: c9a4bb003f34cd8b94eb21679d5d37e0 (MD5) Previous issue date: 2017-02-14 / A plataforma Android ? atualmente a mais popular para o desenvolvimento de aplica??es m?veis, ocupando mais de 80% do mercado de sistemas operacionais para dispositivos m?veis, criando uma demanda por customiza??es de aplica??es para lidar com diferentes dispositivos, tais como, tamanho de tela, poder de processamento e mem?ria dispon?vel, idiomas e necessidades espec?ficas dos usu?rios. J? foram disponibilizadas 23 novas vers?es da plataforma Android desde o seu lan?amento. De forma a permitir a execu??o com sucesso das aplica??es em diferentes dispositivos, ? fundamental oferecer suporte ?s m?ltiplas vers?es da API (Application Programming Interface). Esta disserta??o de mestrado tem como objetivo: analisar, caracterizar e comparar t?cnicas utilizadas por aplica??es Android para oferecer suporte a m?ltiplas vers?es da API. Em especial, o trabalho busca: (i) identificar na literatura quais as t?cnicas indicadas para suporte ?s m?ltiplas vers?es da API Android; (ii) analisar aplica??es reais para quantificar o uso dessas t?cnicas; e (iii) comparar as caracter?sticas e consequ?ncias do uso de tais t?cnicas. Um estudo emp?rico foi conduzido para atingir tal objetivo, no qual foram analisadas 25 aplica??es Android populares. Os resultados do estudo mostram que existem tr?s t?cnicas para prover suporte ?ss m?ltiplas vers?es da API: i) pacote de compatibilidade, variabilidades de granularidade grossa da API que envolvam um conjunto de classes; ii) re-implementa??o de recurso, para situa??es pontuais e granularidade grossa em n?vel de classe ou quando o recurso n?o est? dispon?vel em pacote de compatibilidade; e iii) uso expl?cito da nova API, variabilidades de granularidade fina da API que envolva a chamada de m?todos espec?ficos. Atrav?s da an?lise de 25 aplica??es identificamos que pacote de compatibilidade foi utilizada por 23 aplica??es, re-implementa??o de recurso por 14 e uso expl?cito da nova API por 22. A API de fragmentos cont?m os elementos mais comuns dentre os lan?ados em vers?es superiores da plataforma que s?o usados pelas aplica??es durante sua evolu??o, sendo referenciados por 68% delas. No geral, as aplica??es poderiam aumentar o seu mercado em potencial com adapta??es de, em m?dia, 15 trechos de c?digo, por outro lado, os desenvolvedores das aplica??es t?m se preocupado em evitar c?digo-morto em fun??o da API da plataforma.Na an?lise de 7 aplica??es, 4 delas continham c?digo-morto, mas os quais em geral n?o representam mais do que 0,1% do seu c?digo total. / Android is currently the most popular platformfor the development of mobile applications, representing more than 80% of the operating systems market for mobile devices. This causes demands for application customizations to handle different devices such as screen size, processing power and available memory, languages, and specific user needs. Twenty-three new versions of Android platformhave been released since its first release. In order to enable the successful execution of applications on different devices, it is essential to support multiple versions of the Application Programming Interface (API). This dissertation aims to analyze, characterize and compare techniques used by Android applications to support multiple versions of the API. In particular, the work seeks: (i) to identify the used techniques to support multiple versions of the Android API in the literature; (ii) to analyze real applications to quantify the usage of these techniques; and (iii) to compare the characteristics and consequences of using such techniques. An empirical study, in which 25 popular Android apps were analyzed, was conducted to achieve this goal. The results of the study show that there are three techniques to support multiple versions of the API: i) compatibility package, that adrresses API coarse granularity variabilities involving a set of classes; ii) re-implementation of resource used for specific situations and coarse granularity at class level or when resource is not available in compatibility package; and iii)explicit use of the new API that allows implementing fine grained variabilities of the API that involves calling of specific methods. Through the analysis of 25 applications, we have identified that compatibility package was used by 23 applications, re-implementation of resource was used by 14 applications and the explicit usage of the new API was used by 22 applications. The API fragments contains the most common elements among those released in higher versions of the platformthat are used by applications during their evolution, and it is referenced by 68% of them. In general, applications could increase their potential market with adaptations of, on average, 15 code snippets. On the other hand, application developers have been worried about how avoiding dead code based on platform API. In the analysis of 7 applications, 4 of them contained dead code, but it did not represent more than 0.1% of total code.