Marc J. Fleury

Bio: Marc J. Fleury is an academic researcher. The author has contributed to research in topics: Application server & Enterprise JavaBeans. The author has an hindex of 2, co-authored 2 publications receiving 199 citations.

The JBoss extensible server

Abstract: JBoss is an extensible, reflective, and dynamically reconfigurable Java application server. It includes a set of components that implement the J2EE specification, but its scope goes well beyond J2EE. JBoss is open-ended middleware, in the sense that users can extend middleware services by dynamically deploying new components into a running server. We believe that no other application server currently offers such a degree of extensibility. This paper focuses on two major architectural parts of JBoss: its middleware component model, based on the JMX model, and its meta-level architecture for generalized EJBs. The former requires a novel class loading model, which JBoss implements. The latter includes a powerful and flexible remote method invocation model, based on dynamic proxies, and relies on systematic usage of interceptors as aspect-oriented programming artifacts.

Dynamic Deployment of IIOP-Enabled Components in the JBoss Server

Abstract: JBoss is an extensible Java application server that affords remote access to EJB components via multiple protocols. Its IIOP module supports IIOP-enabled EJBs, which are accessible both to RMI/IIOP clients written in Java and to CORBA clients written in various languages. While other systems use compilation-based approaches to generate IIOP stubs and skeletons, JBoss employs reflective techniques to avoid extra compilation steps and support on-the-fly deployment.

A component-based middleware platform for reconfigurable service-oriented architectures

Abstract: ThetextitService Component Architecture (SCA) is a technology-independent standard for developing distributed Service-oriented Architectures (SOA). The SCA standard promotes the use of components and architecture descriptors, and mostly covers the lifecycle steps of implementation and deployment. Unfortunately, SCA does not address the governance of SCA applications and provides no support for the maintenance of deployed components. This article covers this issue and introduces the FRASCATI platform, a run-time support for SCA with dynamic reconfiguration capabilities and run-time management features. This article presents the internal component-based architecture of the FRASCATI platform, and highlights its key features. The component-based design of the FRASCATI platform introduces many degrees of flexibility and configurability in the platform itself and it can host the SOA applications. This article reports on micro-benchmarks highlighting that run-time manageability in the FRASCATI platform does not decrease its performance when compared with the de facto reference SCA implementation: Apache TUSCANY. Finally, a smart home scenario illustrates the extension capabilities and the various reconfigurations of the FRASCATI platform. Copyright © 2011 John Wiley & Sons, Ltd.

DiscoTect: a system for discovering architectures from running systems

Abstract: One of the challenging problems for software developers is guaranteeing that a system as built is consistent with its architectural design. In this paper, we describe a technique that uses run time observations about an executing system to construct an architectural view of the system. With this technique, we develop mappings that exploit regularities in system implementation and architectural style. These mappings describe how low-level system events can be interpreted as more abstract architectural operations. We describe the current implementation of a tool that uses these mappings, and show that it can highlight inconsistencies between implementation and architecture.

SLA-Driven Clustering of QoS-Aware Application Servers

Abstract: In this paper, we discuss the design, implementation, and experimental evaluation of a middleware architecture for enabling service level agreement (SLA)-driven clustering of QoS-aware application servers. Our middleware architecture supports application server technologies with dynamic resource management: application servers can dynamically change the amount of clustered resources assigned to hosted applications on-demand so as to meet application-level quality of service (QoS) requirements. These requirements can include timeliness, availability, and high throughput and are specified in SLAs. A prototype of our architecture has been implemented using the open-source J2EE application server JBoss. The evaluation of this prototype shows that our approach makes possible JBoss' resource usage optimization and allows JBoss to effectively meet the QoS requirements of the applications it hosts, i.e., to honor the SLAs of those applications

Jolt: lightweight dynamic analysis and removal of object churn

Abstract: It has been observed that component-based applications exhibit object churn, the excessive creation of short-lived objects, often caused by trading performance for modularity. Because churned objects are short-lived, they appear to be good candidates for stack allocation. Unfortunately, most churned objects escape their allocating function, making escape analysis ineffective. We reduce object churn with three contributions. First, we formalize two measures of churn, capture and control (15). Second, we develop lightweight dynamic analyses for measuring both capture and control. Third, we develop an algorithm that uses capture and control to inline portions of the call graph to make churned objects non-escaping, enabling churn optimization via escape analysis. JOLT is a lightweight dynamic churn optimizer that uses our algorithms. We embedded JOLT in the JIT compiler of the IBM J9 commercial JVM, and evaluated JOLT on large application frameworks, including Eclipse and JBoss. We found that JOLT eliminates over 4 times as many allocations as a state-of-the-art escape analysis alone.

Semantic Management of Middleware

Abstract: The Ph.D. proposal addresses the complexity of building distributed applications and systems with Application Servers and Web Services middleware, respectively. Despite their flexible XML-based configuration, taming the ever growing complexity remains all but an easy task. To remedy such problems, the thesis proposes an ontology-based approach to support the management (i.e. development and administration) of Application Server and Web Services based applications. The ontology captures properties of, relationships between and behaviors of the components and services that are required for management purposes. The ontology is an explicit conceptual model with formal logic-based semantics. Therefore its descriptions of components and services may be queried, may foresight required actions, or may be checked to avoid inconsistent system configurations --- during development as well as during run time. Thus, the ontology-based approach retains the original flexibility, but it adds new capabilities for the developer and user of the system.