Maybe I muddled my words on this. Java supports "requesting" thread cancellation, but its not safe to forcibly kill OS threads in any language I know of. For the same reason you can't in Java, finalizers won't run. This includes C and C# among others that use OS threads. https://stackoverflow.com/questions/13285375/how-to-kill-a-r... https://stackoverflow.com/questions/1327102/how-to-kill-a-th...

Notably C lets you do it with the big warning that it can crash everything. C# made the same decision as Java and doesn't allow it.

Java and pretty much all OS thread-using languages DO allow you to end threads by nicely asking them to stop. This is not the same as forcing them to. In all cases, if a thread is stuck in an infinite loop or a blocking call, it probably won't cancel if you ask it to. It depends on whether the thread is written to handle cancellation properly.

This is also a limitation of some languages with fibers, including Erlang. You can't force a thread thats stuck in certain states to stop running in Erlang even though it uses fibers. Some languages with fibers do allow it though.