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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

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 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

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 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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package com.sun.management;

/**

 * Platform-specific management interface for the operating system

 * on which the Java virtual machine is running.

 *

 * <p>

 * The <tt>OperatingSystemMXBean</tt> 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

 */

@jdk.Exported

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 <tt>-1</tt> 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 <tt>-1</tt> if this operation is not supported.

     */

    public long getCommittedVirtualMemorySize();

    /**

     * 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.

     *

     * @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 <tt>-1</tt> if the

     * the platform does not support this operation.

     *

     * @return the CPU time used by the process in nanoseconds,

     * or <tt>-1</tt> if this operation is not supported.

     */

    public long getProcessCpuTime();

    /**

     * Returns the amount of free physical memory in bytes.

     *

     * @return the amount of free physical memory in bytes.

     */

    public long getFreePhysicalMemorySize();

    /**

     * Returns the total amount of physical memory in bytes.

     *

     * @return the total amount of physical memory in  bytes.

     */

    public long getTotalPhysicalMemorySize();

    /**

     * 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.

     *

     * @return the "recent cpu usage" for the whole system; a negative

     * value if not available.

     * @since   1.7

     */

    public double getSystemCpuLoad();

    /**

     * 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();

}