This book constitutes the thoroughly refereed post-proceedings of the 4th International Workshop on Scientific Engineering of Distributed Java Applications, FIDJI 2004, held in Luxembourg-Kirchberg, Luxembourg in November 2004.

The 11 revised full papers presented together with the abstracts of 2 keynote talks and 1 tutorial were carefully selected during two rounds of reviewing and improvement. Among the topics covered are the design of distributed applications; development of reliable and secure distributed systems; software architectures, frameworks, and design patterns; formal methods; model driven software development; Web services; mobility; component-based distributed systems; exceptional handling; UML statecharts; and embedded software.