Interface OperatingSystemMXBean

All Superinterfaces:
OperatingSystemMXBean, PlatformManagedObject
All Known Subinterfaces:
UnixOperatingSystemMXBean
public interface OperatingSystemMXBean extends OperatingSystemMXBean
Platform-specific management interface for the operating system on which the Java virtual machine is running.

This interface provides information about the operating environment on which the Java virtual machine is running. That might be a native operating system, a virtualized operating system environment, or a container-managed environment.

The OperatingSystemMXBean object returned by ManagementFactory.getOperatingSystemMXBean() is an instance of the implementation class of this interface or UnixOperatingSystemMXBean interface depending on its underlying operating system.

Since:
1.5

  • Method Details

    • getCommittedVirtualMemorySize

      long getCommittedVirtualMemorySize()
      Returns the amount of virtual memory that is guaranteed to be available to the running process in bytes, or -1 if this operation is not supported.
      Returns:
      the amount of virtual memory that is guaranteed to be available to the running process in bytes, or -1 if this operation is not supported.

    • getTotalSwapSpaceSize

      long getTotalSwapSpaceSize()
      Returns the total amount of swap space in bytes.
      Returns:
      the total amount of swap space in bytes.

    • getFreeSwapSpaceSize

      long getFreeSwapSpaceSize()
      Returns the amount of free swap space in bytes.
      Returns:
      the amount of free swap space in bytes.

    • getProcessCpuTime

      long getProcessCpuTime()
      Returns the CPU time used by the process on which the Java virtual machine is running in nanoseconds. The returned value is of nanoseconds precision but not necessarily nanoseconds accuracy. This method returns -1 if the the platform does not support this operation.
      Returns:
      the CPU time used by the process in nanoseconds, or -1 if this operation is not supported.

    • getFreePhysicalMemorySize

      @Deprecated(since="14") default long getFreePhysicalMemorySize()
      Deprecated.
      Use getFreeMemorySize() instead of this historically named method.
      Returns the amount of free physical memory in bytes.
      Implementation Requirements:
      This implementation must return the same value as getFreeMemorySize().
      Returns:
      the amount of free physical memory in bytes.

    • getFreeMemorySize

      long getFreeMemorySize()
      Returns the amount of free memory in bytes.
      Returns:
      the amount of free memory in bytes.
      Since:
      14

    • getTotalPhysicalMemorySize

      @Deprecated(since="14") default long getTotalPhysicalMemorySize()
      Deprecated.
      Use getTotalMemorySize() instead of this historically named method.
      Returns the total amount of physical memory in bytes.
      Implementation Requirements:
      This implementation must return the same value as getTotalMemorySize().
      Returns:
      the total amount of physical memory in bytes.

    • getTotalMemorySize

      long getTotalMemorySize()
      Returns the total amount of memory in bytes.
      Returns:
      the total amount of memory in bytes.
      Since:
      14

    • getSystemCpuLoad

      @Deprecated(since="14") default double getSystemCpuLoad()
      Deprecated.
      Use getCpuLoad() instead of this historically named method.
      Returns the "recent CPU usage" for the whole system. This value is a double in the [0.0,1.0] interval. A value of 0.0 means that all CPUs were idle during the recent period of time observed, while a value of 1.0 means that all CPUs were actively running 100% of the time during the recent period being observed. The recent period of observation is implementation-specific, and typically relates to the duration since the last call made to this method, or getCpuLoad(). For the very first invocation, the recent period of observation is undefined. All values between 0.0 and 1.0 are possible dependent on the activities going on. If the recent CPU usage is not available, the method returns a negative value.
      API Note:
      Callers should be aware of the possibility of other callers affecting the observation period and the result.
      Implementation Requirements:
      This implementation must return the same value as getCpuLoad().
      Returns:
      the "recent cpu usage" for the whole system; a negative value if not available.
      Since:
      1.7

    • getCpuLoad

      double getCpuLoad()
      Returns the "recent CPU usage" for the operating environment. This value is a double in the [0.0,1.0] interval. A value of 0.0 means that all CPUs were idle during the recent period of time observed, while a value of 1.0 means that all CPUs were actively running 100% of the time during the recent period being observed. The recent period of observation is implementation-specific, and typically relates to the duration since the last call made to this method, or getSystemCpuLoad(). For the very first invocation, the recent period of observation is undefined. All values between 0.0 and 1.0 are possible dependent on the activities going on. If the recent CPU usage is not available, the method returns a negative value.
      API Note:
      Callers should be aware of the possibility of other callers affecting the observation period and the result.
      Returns:
      the "recent cpu usage" for the whole operating environment; a negative value if not available.
      Since:
      14

    • getProcessCpuLoad

      double getProcessCpuLoad()
      Returns the "recent CPU usage" for the Java Virtual Machine process. This value is a double in the [0.0,1.0] interval. A value of 0.0 means that none of the CPUs were running threads from the JVM process during the recent period of time observed, while a value of 1.0 means that all CPUs were actively running threads from the JVM 100% of the time during the recent period being observed. Threads from the JVM include the application threads as well as the JVM internal threads. The recent period of observation is implementation-specific, and typically relates to the duration since the last call made to this method. For the very first invocation, the recent period of observation is undefined. All values between 0.0 and 1.0 are possible dependent on the activities going on in the JVM process and the whole system. If the Java Virtual Machine recent CPU usage is not available, the method returns a negative value.
      API Note:
      Callers should be aware of the possibility of other callers affecting the observation period and the result.
      Returns:
      the "recent cpu usage" for the Java Virtual Machine process; a negative value if not available.
      Since:
      1.7