Suddenly I've found out that jstat is deprecated:
The jstat tool displays performance statistics for an instrumented HotSpot Java virtual machine (JVM). The target JVM is identified by its virtual machine identifier, or vmid option described below.
NOTE: This utility is unsupported and may not be available in future versions of the J2SE SDK. It is not currently available on Windows 98 and Windows ME platforms.
I haven't developed anything on Windows for years, but nevertheless the question is - what should I use instead, which tool (or set of tools) nowadays is considered the best substitute for that kind of monitoring I can get using jstat?
Update: pure CLI tools are preferable.
The documentation says that it's unsupported (not quite deprecated yet) since JDK 5 (which you linked), yet it's still present in JDK 6, 7 and OpenJDK 8. I'm not too worried about its disappearance in the short term, especially since it doesn't have a replacement (jcmd doesn't have an equivalent command).
Besides, the tools and utilities directory says it is supported, except on Windows 98 & ME. Then again it says right above that it's unsupported and experimental..
One caveat though: last time I checked, it didn't support G1, but then, neither did JConsole/JVisualVM. It doesn't mean it can't be adapted.