Abstract:

Aiming at the disadvantages in dynamics and algorithm time complexity in the existing web service composition methods, we propose an adjacency matrixbased web service composition approach. Sequential and parallel relationship among web services is represented by adjacency matrix. Abstract services are created by clustering, and the composition relationship among abstract services is established by domain experts. The Warshall algorithm is utilized to calculate the transitive closure of the adjacency matrix so that we can judge whether the  the service request is met or not. Meanwhile the dynamic service composition flow is constructed. The proposed method applies well in service composition due to its simple operation and the O(n3) time complexity of the Warshall algorithm.

Key words: web service;service composition;adjacency matrix;transitive closure;Warshall algorithm