As a popular infrastructure for distributed systems running on the Internet, middleware has to support much more diverse and complex interactions for coping with the drastically increasing demand on information technology and the extremely open and dynamic nature of the Internet. These supporting mechanisms facilitate the development, deployment, and integration of distributed systems, as well as increase the occasions for distributed systems to interact in an undesired way. The undesired interactions may cause serious problems, such as quality violation, function loss, and even system crash. In this paper, the problem is studied from the perspective of the feature interaction problem (FIP) in telecom, and an online approach to the detection and solution on runtime systems is proposed. Based on a classification of middleware enabled interactions, the existence of FIP in middleware based systems is illustrated by four real cases and a conceptual comparison between middleware based systems and telecom systems. After that, runtime software architecture is employed to facilitate the online detection and solution of FIP. The approach is demonstrated on J2EE (Java 2 Platform Enterprise Edition) and applied to detect and resolve all of the four real cases.
HUANG Gang1,2 LIU XuanZhe1,2 & MEI Hong1,2 1 Key Laboratory of High Confidence Software Technologies, Ministry of Education, Peking University, Beijing 1000871, China
As a new software paradigm evolved by the Internet, Internetware brings many challenges for the traditional software development methods and techniques. Though architecture-based component composition (ABC) approach is originated in the traditional software paradigm, it supports the engineering of Internetware effectively due to its philosophy, rationales and mechanisms. ABC has three major contributions to the en- gineering of Internetware in detail. First, the feature oriented domain modeling method can structure the "disordered" "software entities" to "ordered Internetware" bottom-up in the problem space. Second, the architecture centric design and analysis method can support the development of self-adaptive Internetware. Third, the component operating platform is a reflective and self-adaptive middleware that not only provides Internetware with a powerful and flexible runtime infrastructure but also enables the self-adaptation of the structure and individual entities of Internetware.
Being one of the basic features of Internetware, self-adaptation means that the software system can monitor its runtime state and behavior and adjust them when necessary according to pre-defined policies. Focusing on the three fundamental issues of self-adaptation, including the scope, operability and trustworthiness, a software architecture (SA) centric approach for Internetware's self-adaptation is presented in this paper. All of the self-adaptive actions, i.e. monitoring, analyzing, planning and executing, are performed based on SA. In detail, runtime state and behavior of Internetware are represented and changed in the form of runtime soft- ware architecture. The knowledge for self-adaptation is captured, organized and reasoned in the form of SA so that automatic analysis and decision-making are achieved.
MEI Hong1,2, HUANG Gang1,2, LAN Ling1,2 & LI JunGuo1,2 1 Key Laboratory of High Confidence Software Technologies (Peking University), Ministry of Education, Beijing 100871, China