To continue in the Java vein: weren't Eclipse SWT & RCP supposed to be the ultimate answer to native cross platform UI development in Java? I had no experience

To continue in the Java vein: weren't Eclipse SWT & RCP supposed to be the ultimate answer to native cross platform UI development in Java? I had no experience with them: did they gain some adoption or recognition at least? Maybe all cross-platforms app solutions are just doomed to stagnate, at least until the next hype one rises, after all.