How to know JDK version from within Java code

问题:

How to know JDK version from within Java code

回答1:

I presume you mean just the Java version, in which case try this:

String version = System.getProperty("java.version");

回答2:

Relying on the java.version string for anything else than showing to a human is fragile and will break if running on another Java implementation.

The only reliable way programatically is to use reflection to carefully ask if a given facility is available, and then select the appropriate code accordingly.

回答3:

If you need to know the bit version(32bit or 64 bit) as well, and you are running a hotSpot JVM, you can try this code:

System.getProperty("sun.arch.data.model")

No grantee that it will work for other Java implementaions rather than hotSpot.