A problem solving environment (PSE) provides all computational facilities necessary for solving a target class of problems efficiently. PSEs are used primarily for domain-specific problem-solving in science and engineering and aim to ease the burden of advanced scientific computing. Scientific problem solving, however, often involves the use of legacy resources which are difficult to modify or port, and may be distributed on different machines. Existing PSEs provide little support for solving such problems in a generic framework.

This thesis investigates the design of a platform-independent system that enables problem solving using legacy resources without having to modify legacy code. It presents Symphony, an open and extensible Java-based framework for composition and manipulation of distributed legacy resources. Symphony allows users to compose visually a collection of programs and data by specifying data-flow relationships among them and provides a client/server framework for transparently executing the composed application. Additionally, the framework is web-aware and helps integrate web-based resources with legacy resources. It also enables programmers to provide a graphical interface to legacy applications and to write visualization components.

Symphony uses Sun Microsystems' JavaBeans component architecture for providing components that represent legacy resources. These components can be customized and composed in any standard JavaBeans builder tool. Executable components communicate with a server, implemented using Java Remote Method Invocation mechanism, for executing remote legacy applications. Symphony enables extensibility by providing abstract components which can be extended by implementing simple interfaces. Beans implemented from the abstract beans can act as data producers, consumers or filters.