Check if the operating system is 64-bit

Scratch.java

import com.sun.jna.Platform;
import com.sun.jna.platform.win32.Kernel32;
import com.sun.jna.platform.win32.Kernel32Util;
import com.sun.jna.platform.win32.WinNT;
import com.sun.jna.ptr.IntByReference;

class Scratch {

    public static void main(final String[] args) {
        System.out.println("Is 64-bit OS? " + is64BitOS());
    }

    public static boolean is64BitOS() {
        return Platform.is64Bit() || (Platform.isWindows() && isRunningUnderWow64());
    }

    private static boolean isRunningUnderWow64() throws UnsatisfiedLinkError, RuntimeException {
        final IntByReference res = new IntByReference();
        final WinNT.HANDLE currentProcess = Kernel32.INSTANCE.GetCurrentProcess();
        if (!Kernel32.INSTANCE.IsWow64Process(currentProcess, res)) {
            // TODO: Do something more sensible.
            throw new RuntimeException("Failed to check if the current process is running under WOW64. " + Kernel32Util.getLastErrorMessage());
        }
        return res.getValue() != 0;
    }
}