unable to acess ProcessCpuTime,SystemCpuLoad methods

Question

I want to collect Operating Systems Parameters..in my mbean so that after registering it i can see those values on JConsole..I have collected some parameters but I cant collect the values for ProcessCpuTime,SystemCpuLoad I tried it with OperatingSystemMXBean interface object but it doesn't work. Also i read on google that those method needs APIs which are not supported on Windows.So is there another way to calculate those values mathematically...Please help me

Answer 1

The Windows JVM implementation of java.lang.management.OperatingSystemMXBean is com.sun.management.OperatingSystem. You can reference it directly by casting the former:

import java.lang.management.*;
import com.sun.management.*;
...
OperatingSystem os = (OperatingSystem)ManagementFactory.getOperatingSystemMXBean();

There's some variability between the Java 6 and java 7 versions of this class, which can be observed with this Groovy script:

import java.lang.management.*;

os = ManagementFactory.getOperatingSystemMXBean();
println os.getClass().getName();

try { println "Process CPU Load:${os.getProcessCpuLoad()}"; } catch (e) {}
try { println "Process CPU Time:${os.getProcessCpuTime()}"; } catch (e) {}
try { println "System CPU Load:${os.getSystemCpuLoad()}"; } catch (e) {}

Java 6 Output:

com.sun.management.OperatingSystem

Process CPU Time:79810111600

Java 7 Output:

com.sun.management.OperatingSystem

Process CPU Load:-1.0

Process CPU Time:1840811800

System CPU Load:0.4902940980431365

So it's not as useful as the Linux [et.al.] variant, but you might get what you're looking for.