a programming environment for web services
PEWS is a programming language for the definition of web service interfaces. PEWS programs can be used for the description of both simple and composite web services. Simple web services can be built from scratch, by the combination of (WSDL) operations. Each operation must be implemented as a Java method. Composite web services are constructed from the combination of existing web services, accessed by using their WSDL descriptions. PEWS combinators help to define the order in which web services and operations will be performed. PEWS has a human-readable syntax as well as a XML version, called XPEWS. The human-readable language is intended to help in the design of web services and in the formal reasoning about programs. XPEWS is used as an interface language between the front-end and back-end of the PEWS language processor. This paper presents the development of a computational environment for PEWS. The front-end of the environment is an Eclipse plug-in. The use of the front-end can help reducing the time for development of the compositions, by the verification of codification errors and the generation XPEWS documents. The back-end of PEWS is responsible for the implementation of the web services described in a XPEWS document. The back-end produces Java code (skeletons) to call the web service operations and performs them in the order defined by the XPEWS document.
pews front-end back-end