Interface RuntimeMXBean

All Superinterfaces:

PlatformManagedObject, RuntimeMXBean

public interface RuntimeMXBean
extends RuntimeMXBean

The OpenJ9 extension interface for the runtime system of the virtual machine.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static enum	RuntimeMXBean.VMIdleStates	Defines the different states of getVMIdleState().

Method Summary

Modifier and Type	Method	Description
double	getCPULoad()	Returns a double value which holds the system load average calculated for the minute preceding the call, where system load average is taken to mean the following:
double	getVMGeneratedCPULoad()	Returns a system load average calculated over the minute preceding the call averaged over the number of CPU available to Java virtual machine process.
String	getVmId()	This is provided for the benefit of applications which use attach API to load JVMTI agents into their own JVMs.
RuntimeMXBean.VMIdleStates	getVMIdleState()	Returns current JVM Idle state.
boolean	isAttachApiInitialized()	Query the state of the Attach API.
boolean	isAttachApiTerminated()	Query the state of the Attach API.
boolean	isVMIdle()

Methods declared in interface PlatformManagedObject

getObjectName

Modifier and Type	Method	Description
ObjectName	getObjectName()	Returns an ObjectName instance representing the object name of this platform managed object.

Methods declared in interface RuntimeMXBean

getBootClassPath, getClassPath, getInputArguments, getLibraryPath, getManagementSpecVersion, getName, getPid, getSpecName, getSpecVendor, getSpecVersion, getStartTime, getSystemProperties, getUptime, getVmName, getVmVendor, getVmVersion, isBootClassPathSupported

Modifier and Type	Method	Description
String	getBootClassPath()	Returns the boot class path that is used by the bootstrap class loader to search for class files.
String	getClassPath()	Returns the Java class path that is used by the system class loader to search for class files.
List<String>	getInputArguments()	Returns the input arguments passed to the Java virtual machine which does not include the arguments to the main method.
String	getLibraryPath()	Returns the Java library path.
String	getManagementSpecVersion()	Returns the version of the specification for the management interface implemented by the running Java virtual machine.
String	getName()	Returns the name representing the running Java virtual machine.
default long	getPid()	Returns the process ID representing the running Java virtual machine.
String	getSpecName()	Returns the Java virtual machine specification name.
String	getSpecVendor()	Returns the Java virtual machine specification vendor.
String	getSpecVersion()	Returns the Java virtual machine specification version.
long	getStartTime()	Returns the start time of the Java virtual machine in milliseconds.
Map<String,String>	getSystemProperties()	Returns a map of names and values of all system properties.
long	getUptime()	Returns the uptime of the Java virtual machine in milliseconds.
String	getVmName()	Returns the Java virtual machine implementation name.
String	getVmVendor()	Returns the Java virtual machine implementation vendor.
String	getVmVersion()	Returns the Java virtual machine implementation version.
boolean	isBootClassPathSupported()	Tests if the Java virtual machine supports the boot class path mechanism used by the bootstrap class loader to search for class files.

Method Details

getCPULoad

double getCPULoad()

Returns a double value which holds the system load average calculated for the minute preceding the call, where system load average is taken to mean the following:

The time-averaged value of the sum of the number of runnable entities running on the available processors and the number of runnable entities ready and queued to run on the available processors. The averaging technique adopted can vary depending on the underlying operating system.

Returns:

normally, the system load average as a double. If the system load average is not obtainable (e.g. because the calculation may involve an unacceptable performance impact) then a negative value is returned.

Since:

1.6

See Also:

• OperatingSystemMXBean.getSystemLoadAverage()

getVMGeneratedCPULoad

double getVMGeneratedCPULoad()

Returns a system load average calculated over the minute preceding the call averaged over the number of CPU available to Java virtual machine process.

Returns:

A double indicating the average system load per processor. If the system load average is not available, it returns a negative value to indicate this.

getVMIdleState

RuntimeMXBean.VMIdleStates getVMIdleState()

Returns current JVM Idle state.

Returns:

JVM idle state value - i.e active / idle

isVMIdle

boolean isVMIdle()

Returns:

true if JVM state is idle. Otherwise returns false

isAttachApiInitialized

boolean isAttachApiInitialized()

Query the state of the Attach API. Return false if the Attach API is: - still initializing - disabled - terminated by VM shutdown

Returns:

true if Attach API is initialized

Since:

1.8

isAttachApiTerminated

boolean isAttachApiTerminated()

Query the state of the Attach API. Return true if the Attach API is: - disabled - terminated by VM shutdown and false if it is - still initializing - initialized and running

Returns:

true if Attach API is terminated

Since:

1.8

getVmId

String getVmId()

This is provided for the benefit of applications which use attach API to load JVMTI agents into their own JVMs.

Returns:

Attach API Virtual Machine ID of this VM

Since:

1.8