5 Avaliação de Desempenho
6.2 Trabalhos Futuros
O modelo de middleware proposto pode ser refinado para no futuro suportar as seguintes características:
• Interface gráfica para definição dos meta-dados. Uma interface intuitiva facilita bastante o entendimento do usuário sobre um determinado software, principalmente no momento da utilização de uma nova ferramenta. No modelo adaptativo proposto, a utilização de uma interface amigável otimizaria a definição dos meta-dados. Esta interface receberia os dados relativos à adaptação informadas pelo usuário e os transformaria nos arquivos XML de meta-dados definidos pelo modelo. É necessário observar que, apesar de XML ser uma linguagem bastante conhecida e difundida na Internet, o uso de interfaces gráficas que realizam geração automática de arquivos XML é sempre bem vinda para o usuário, pois o deixa livre de preocupações como seguir regras de definições de documentos XML. A própria interface se preocuparia com estas regras.
• Criação de API’s de serviços e monitores do ambiente de execução. Isto desoneraria o desenvolvedor da aplicação distribuída de ter que implementar uma grande parte dos serviços não-funcionais de que necessita. Também o deixaria livre de ter que implementar monitores de ambiente. Utilizando uma API, tudo que o desenvolvedor teria que fazer seria escolher que serviços e monitores ele iria utilizar, pondo estas informações nos meta-dados.
• Versão do modelo para ambientes móveis. Ambientes móveis são uma importante área na qual adaptação é primordial. O protótipo do modelo que não se utiliza de reflexão é o mais indicado para servir como base para este trabalho, por ter apresentado um melhor desempenho. É necessário notar que ambientes móveis possuem uma série de restrições, como poder de processamento e largura de banda. Assim, um middleware para estes ambientes deve ser extremamente leve, economizando ao máximo os recursos do dispositivo no qual estiver executando.
de sincronização de dados multimídia, o modelo precisará trabalhar com a adaptação de grupos de mensagens, característica que ficou fora do escopo do presente trabalho. A adaptação de grupos de mensagens é necessária no caso de multimídia pois uma única invocação de um cliente a um servidor resulta no envio de vários dados em canais diferentes, onde enquanto um determinado canal transmite o áudio, o outro estará transmitindo o vídeo.
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