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package com.sun.management;


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. 
Author: Mandy Chung
Since:  1.5
/**
 * Platform-specific management interface for the operating system
 * on which the Java virtual machine is running.
 *
 * <p>
 * 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.
 *
 * <p>
 * The {@code OperatingSystemMXBean} object returned by
 * {@link java.lang.management.ManagementFactory#getOperatingSystemMXBean()}
 * is an instance of the implementation class of this interface
 * or {@link UnixOperatingSystemMXBean} interface depending on
 * its underlying operating system.
 *
 * @author  Mandy Chung
 * @since   1.5
 */
public interface OperatingSystemMXBean extends
    java.lang.management.OperatingSystemMXBean {

    
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.
/**
     * Returns the amount of virtual memory that is guaranteed to
     * be available to the running process in bytes,
     * or {@code -1} if this operation is not supported.
     *
     * @return the amount of virtual memory that is guaranteed to
     * be available to the running process in bytes,
     * or {@code -1} if this operation is not supported.
     */
    public long getCommittedVirtualMemorySize();

    
Returns the total amount of swap space in bytes.

Returns:the total amount of swap space in bytes.
/**
     * Returns the total amount of swap space in bytes.
     *
     * @return the total amount of swap space in bytes.
     */
    public long getTotalSwapSpaceSize();

    
Returns the amount of free swap space in bytes.

Returns:the amount of free swap space in bytes.
/**
     * Returns the amount of free swap space in bytes.
     *
     * @return the amount of free swap space in bytes.
     */
    public long getFreeSwapSpaceSize();

    
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.
/**
     * 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 {@code -1} if the
     * the platform does not support this operation.
     *
     * @return the CPU time used by the process in nanoseconds,
     * or {@code -1} if this operation is not supported.
     */
    public long getProcessCpuTime();

    
Returns the amount of free physical memory in bytes.

Deprecated:Use getFreeMemorySize() instead of this historically named method.
Implementation Requirements:This implementation must return the same value as getFreeMemorySize().
Returns:the amount of free physical memory in bytes.
/**
     * Returns the amount of free physical memory in bytes.
     *
     * @deprecated Use {@link #getFreeMemorySize()} instead of
     * this historically named method.
     *
     * @implSpec This implementation must return the same value
     * as {@link #getFreeMemorySize()}.
     *
     * @return the amount of free physical memory in bytes.
     */
    @Deprecated(since="14")
    public default long getFreePhysicalMemorySize() { return getFreeMemorySize(); }

    
Returns the amount of free memory in bytes.

Returns:the amount of free memory in bytes.
Since:14
/**
     * Returns the amount of free memory in bytes.
     *
     * @return the amount of free memory in bytes.
     * @since 14
     */
    public long getFreeMemorySize();

    
Returns the total amount of physical memory in bytes.

Deprecated:Use getTotalMemorySize() instead of this historically named method.
Implementation Requirements:This implementation must return the same value as getTotalMemorySize().
Returns:the total amount of physical memory in  bytes.
/**
     * Returns the total amount of physical memory in bytes.
     *
     * @deprecated Use {@link #getTotalMemorySize()} instead of
     * this historically named method.
     *
     * @implSpec This implementation must return the same value
     * as {@link #getTotalMemorySize()}.
     *
     * @return the total amount of physical memory in  bytes.
     */
    @Deprecated(since="14")
    public default long getTotalPhysicalMemorySize() { return getTotalMemorySize(); }

    
Returns the total amount of memory in bytes.

Returns:the total amount of memory in  bytes.
Since:14
/**
     * Returns the total amount of memory in bytes.
     *
     * @return the total amount of memory in  bytes.
     * @since 14
     */
    public long getTotalMemorySize();

    
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. All values betweens 0.0 and
1.0 are possible depending of the activities going on in the system.
If the system recent cpu usage is not available, the method returns a
negative value.

Deprecated:Use getCpuLoad() instead of this historically named method.
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
/**
     * 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. All values betweens 0.0 and
     * 1.0 are possible depending of the activities going on in the system.
     * If the system recent cpu usage is not available, the method returns a
     * negative value.
     *
     * @deprecated Use {@link #getCpuLoad()} instead of
     * this historically named method.
     *
     * @implSpec This implementation must return the same value
     * as {@link #getCpuLoad()}.
     *
     * @return the "recent cpu usage" for the whole system; a negative
     * value if not available.
     * @since   1.7
     */
    @Deprecated(since="14")
    public default double getSystemCpuLoad() { return 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. All values betweens 0.0 and
1.0 are possible depending of the activities going on.
If the recent cpu usage is not available, the method returns a
negative value.

Returns:the "recent cpu usage" for the whole operating environment;
a negative value if not available.
Since:14
/**
     * 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. All values betweens 0.0 and
     * 1.0 are possible depending of the activities going on.
     * If the recent cpu usage is not available, the method returns a
     * negative value.
     *
     * @return the "recent cpu usage" for the whole operating environment;
     * a negative value if not available.
     * @since 14
     */
    public double getCpuLoad();

    
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. All values
betweens 0.0 and 1.0 are possible depending of 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.

Returns:the "recent cpu usage" for the Java Virtual Machine process;
a negative value if not available.
Since:  1.7
/**
     * 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. All values
     * betweens 0.0 and 1.0 are possible depending of 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.
     *
     * @return the "recent cpu usage" for the Java Virtual Machine process;
     * a negative value if not available.
     * @since   1.7
     */
    public double getProcessCpuLoad();

}