"Benefitting the ecosystem" doesn't bear on fair use at all, but if it did, one could point to Android driving a revival of Java generally, and dragging client-

"Benefitting the ecosystem" doesn't bear on fair use at all, but if it did, one could point to Android driving a revival of Java generally, and dragging client-end Java coding out of a coma and into prominence. The same could have been said of Visual J++ but Sun killed that opportunity before it could really flourish.