Red Hat's Scott Stark, vice president of architecture for the company's JBoss group, expressed a number of concerns about how applications would work with the module system and its potential impact on the planned Java Enterprise Edition 9. Stark also said the module system, which is featured in Java Specification Request 376 and Project Jigsaw, could result in two worlds of Java: one for Jigsaw and one for everything else, including Java SE classloaders and OSGI. Stark's analysis received input from others in the Java community, including Sonatype.
"The result will be a weakened Java ecosystem at a time when rapid change is occurring in the server space with increasing use of languages like Go," Stark wrote, also predicting major challenges for applications dealing with services and reflection. His critique adds that "In some cases the implementation...contradicts years of modular application deployment best practices that are already commonly employed by the ecosystem as a whole." And he ultimately concludes that this effort to modularize Java has limitations which "almost certainly prevent the possibility of Java EE 9 from being based on Jigsaw, as to do so would require existing Java EE vendors to completely throw out compatibility, interoperability, and feature parity with past versions of the Java EE specification."