"Java the language is almost irrelevant. It's the design of the Java Virtual Machine. And I've seen compilers for ML, compilers for Scheme, compilers for Ada, and they all work. Not many people use them, but it doesn't matter: they all work." --James Gosling
Then Microsoft happened. MS realized that "Write Once, Run Anywhere" kills their OS monopoly, so they polluted Java with brilliant Embrace, Extend, Extinguish strategy (Sun vs. Microsoft revealed the emails where the stated goal was "Kill cross-platform Java" by growing the "polluted" Java market.):
Embrace: Microsoft licensed Java from Sun Microsystems and built the MSJVM. It was the fastest JVM for some time.
Extend: They created a programmer tool for Java with proprietary Windows-specific "extensions" and also removed standard features like RMI and JNI.
Extinguish: Developers using MS tools (90% of devlopers at the time) produced "Write Once, Run Only on Windows" software and killed it and pivoted to C# and .NET