com.ibm.lang.management

Class MemoryPoolMXBeanImpl

java.lang.Object

com.ibm.lang.management.DynamicMXBeanImpl

com.ibm.lang.management.MemoryPoolMXBeanImpl

All Implemented Interfaces:

java.lang.management.MemoryPoolMXBean, javax.management.DynamicMBean

public final class MemoryPoolMXBeanImpl
extends DynamicMXBeanImpl
implements MemoryPoolMXBean

Runtime type for MemoryPoolMXBean

Since:

1.5

Field Summary

Fields inherited from class com.ibm.lang.management.DynamicMXBeanImpl

info

Method Summary

Methods

Modifier and Type	Method and Description
java.lang.management.MemoryUsage	getCollectionUsage() If supported by the virtual machine, returns a MemoryUsagewhich encapsulates this memory pool's memory usage after the most recent run of the garbage collector.
long	getCollectionUsageThreshold() Returns this memory pool's collection usage threshold.
long	getCollectionUsageThresholdCount() Returns the number of times that the memory usage for this memory pool has grown to exceed the collection usage threshold.
java.lang.String[]	getMemoryManagerNames() Returns a string array containing the unique names of each memory manager that manages this memory pool.
java.lang.String	getName() Returns the name of this memory pool.
java.lang.management.MemoryUsage	getPeakUsage() Returns information on the peak usage of the memory pool.
java.lang.management.MemoryUsage	getPreCollectionUsage() If supported by the virtual machine, returns a MemoryUsagewhich encapsulates this memory pool's memory usage before the most recent run of the garbage collector.
java.lang.management.MemoryType	getType() Returns the memory pool's type.
java.lang.management.MemoryUsage	getUsage() Returns the current memory usage of this memory pool as estimated by the virtual machine.
long	getUsageThreshold() Returns this memory pool's usage threshold.
long	getUsageThresholdCount() Returns the number of times that the memory usage for this memory pool has grown to exceed the current usage threshold.
boolean	isCollectionUsageThresholdExceeded() Returns a boolean indication of whether or not this memory pool hit or exceeded the current value of the collection usage threshold after the latest garbage collection run.
boolean	isCollectionUsageThresholdSupported() Returns a boolean indication of whether or not this memory pool supports a collection usage threshold.
boolean	isUsageThresholdExceeded() Returns a boolean indication of whether or not this memory pool has hit or has exceeded the current value of the usage threshold.
boolean	isUsageThresholdSupported() Returns a boolean indication of whether or not this memory pool supports a usage threshold.
boolean	isValid() Returns a boolean indication of whether or not this memory pool may still be considered valid.
void	resetPeakUsage() Updates this memory pool's memory usage peak value to be whatever the value of the current memory usage is.
void	setCollectionUsageThreshold(long threshold) Updates this memory pool to have a new value for its collection usage threshold.
void	setUsageThreshold(long threshold) Updates this memory pool to have a new value for its usage threshold.

Methods inherited from class com.ibm.lang.management.DynamicMXBeanImpl

getAttribute, getAttributes, getMBeanInfo, getPresentAttribute, getPresentOperation, initMBeanInfo, invoke, setAttribute, setAttributes, setMBeanInfo

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

getCollectionUsage

public java.lang.management.MemoryUsage getCollectionUsage()

Description copied from interface: java.lang.management.MemoryPoolMXBean

If supported by the virtual machine, returns a MemoryUsagewhich encapsulates this memory pool's memory usage after the most recent run of the garbage collector. No garbage collection will be actually occur as a result of this method getting called.

Specified by:

getCollectionUsage in interface java.lang.management.MemoryPoolMXBean

Returns:

a MemoryUsageobject that may be interrogated by the caller to determine the details of the memory usage. Returns null if the virtual machine does not support this method.

getPreCollectionUsage

public java.lang.management.MemoryUsage getPreCollectionUsage()

Description copied from interface: MemoryPoolMXBean

If supported by the virtual machine, returns a MemoryUsagewhich encapsulates this memory pool's memory usage before the most recent run of the garbage collector. No garbage collection will be actually occur as a result of this method getting called.

The method will return a null if the virtual machine does not support this type of functionality.

MBeanServer access:

The return value will be mapped to a CompositeData with attributes as specified in MemoryUsage.

Returns:

a MemoryUsage containing the usage details for the memory pool just before the most recent collection occurred.

getCollectionUsageThreshold

public long getCollectionUsageThreshold()

Description copied from interface: java.lang.management.MemoryPoolMXBean

Returns this memory pool's collection usage threshold.

Specified by:

getCollectionUsageThreshold in interface java.lang.management.MemoryPoolMXBean

Returns:

the collection usage threshold in bytes. The default value as set by the virtual machine will be zero.

See Also:

MemoryPoolMXBean.isCollectionUsageThresholdSupported()

getCollectionUsageThresholdCount

public long getCollectionUsageThresholdCount()

Description copied from interface: java.lang.management.MemoryPoolMXBean

Returns the number of times that the memory usage for this memory pool has grown to exceed the collection usage threshold.

Specified by:

getCollectionUsageThresholdCount in interface java.lang.management.MemoryPoolMXBean

Returns:

a count of the number of times that the collection usage threshold has been surpassed.

See Also:

MemoryPoolMXBean.isCollectionUsageThresholdSupported()

getMemoryManagerNames

public java.lang.String[] getMemoryManagerNames()

Description copied from interface: java.lang.management.MemoryPoolMXBean

Returns a string array containing the unique names of each memory manager that manages this memory pool. A memory pool will always have at least one memory manager associated with it.

Specified by:

getMemoryManagerNames in interface java.lang.management.MemoryPoolMXBean

Returns:

the names of all the memory managers for this memory pool.

getName

public java.lang.String getName()

Description copied from interface: java.lang.management.MemoryPoolMXBean

Returns the name of this memory pool.

Specified by:

getName in interface java.lang.management.MemoryPoolMXBean

Returns:

the name of this memory pool.

getPeakUsage

public java.lang.management.MemoryUsage getPeakUsage()

Description copied from interface: java.lang.management.MemoryPoolMXBean

Returns information on the peak usage of the memory pool. The scope of this covers all elapsed time since either the start of the virtual machine or the peak usage was reset.

Specified by:

getPeakUsage in interface java.lang.management.MemoryPoolMXBean

Returns:

a MemoryUsagewhich can be interrogated by the caller to determine details of the peak memory usage. A null value will be returned if the memory pool no longer exists (and the pool is therefore considered to be invalid).

See Also:

MemoryPoolMXBean.resetPeakUsage(), MemoryPoolMXBean.isValid()

getType

public java.lang.management.MemoryType getType()

Description copied from interface: java.lang.management.MemoryPoolMXBean

Returns the memory pool's type.

Specified by:

getType in interface java.lang.management.MemoryPoolMXBean

Returns:

a MemoryTypevalue indicating the type of the memory pool (heap or non-heap).

getUsage

public java.lang.management.MemoryUsage getUsage()

Description copied from interface: java.lang.management.MemoryPoolMXBean

Returns the current memory usage of this memory pool as estimated by the virtual machine.

Specified by:

getUsage in interface java.lang.management.MemoryPoolMXBean

Returns:

an instance of MemoryUsagethat can be interrogated by the caller to determine details on the pool's current memory usage. A null value will be returned if the memory pool no longer exists (in which case it is considered to be invalid).

See Also:

MemoryPoolMXBean.isValid()

getUsageThreshold

public long getUsageThreshold()

Description copied from interface: java.lang.management.MemoryPoolMXBean

Returns this memory pool's usage threshold.

Specified by:

getUsageThreshold in interface java.lang.management.MemoryPoolMXBean

Returns:

the usage threshold in bytes. The default value as set by the virtual machine depends on the platform the virtual machine is running on. will be zero.

See Also:

MemoryPoolMXBean.isUsageThresholdSupported(), MemoryPoolMXBean.setUsageThreshold(long)

getUsageThresholdCount

public long getUsageThresholdCount()

Description copied from interface: java.lang.management.MemoryPoolMXBean

Returns the number of times that the memory usage for this memory pool has grown to exceed the current usage threshold.

Specified by:

getUsageThresholdCount in interface java.lang.management.MemoryPoolMXBean

Returns:

a count of the number of times that the usage threshold has been surpassed.

See Also:

MemoryPoolMXBean.isUsageThresholdSupported()

isCollectionUsageThresholdExceeded

public boolean isCollectionUsageThresholdExceeded()

Description copied from interface: java.lang.management.MemoryPoolMXBean

Returns a boolean indication of whether or not this memory pool hit or exceeded the current value of the collection usage threshold after the latest garbage collection run.

Specified by:

isCollectionUsageThresholdExceeded in interface java.lang.management.MemoryPoolMXBean

Returns:

true if the collection usage threshold was surpassed after the latest garbage collection run, otherwise false.

See Also:

MemoryPoolMXBean.isCollectionUsageThresholdSupported()

isCollectionUsageThresholdSupported

public boolean isCollectionUsageThresholdSupported()

Description copied from interface: java.lang.management.MemoryPoolMXBean

Returns a boolean indication of whether or not this memory pool supports a collection usage threshold.

Specified by:

isCollectionUsageThresholdSupported in interface java.lang.management.MemoryPoolMXBean

Returns:

true if supported, false otherwise.

isUsageThresholdExceeded

public boolean isUsageThresholdExceeded()

Description copied from interface: java.lang.management.MemoryPoolMXBean

Returns a boolean indication of whether or not this memory pool has hit or has exceeded the current value of the usage threshold.

Specified by:

isUsageThresholdExceeded in interface java.lang.management.MemoryPoolMXBean

Returns:

true if the usage threshold has been surpassed, otherwise false.

See Also:

MemoryPoolMXBean.isUsageThresholdSupported()

isUsageThresholdSupported

public boolean isUsageThresholdSupported()

Description copied from interface: java.lang.management.MemoryPoolMXBean

Returns a boolean indication of whether or not this memory pool supports a usage threshold.

Specified by:

isUsageThresholdSupported in interface java.lang.management.MemoryPoolMXBean

Returns:

true if supported, false otherwise.

isValid

public boolean isValid()

Description copied from interface: java.lang.management.MemoryPoolMXBean

Returns a boolean indication of whether or not this memory pool may still be considered valid. A memory pool becomes invalid once it has been removed by the virtual machine.

Specified by:

isValid in interface java.lang.management.MemoryPoolMXBean

Returns:

true if the memory pool has not been removed by the virtual machine, false otherwise.

resetPeakUsage

public void resetPeakUsage()

Description copied from interface: java.lang.management.MemoryPoolMXBean

Updates this memory pool's memory usage peak value to be whatever the value of the current memory usage is.

Specified by:

resetPeakUsage in interface java.lang.management.MemoryPoolMXBean

See Also:

ManagementPermission

setCollectionUsageThreshold

public void setCollectionUsageThreshold(long threshold)

Description copied from interface: java.lang.management.MemoryPoolMXBean

Updates this memory pool to have a new value for its collection usage threshold. Only values of zero or greater should be supplied. A zero value effectively turns off any further checking of collection memory usage by the virtual machine. A value greater than zero establishes the new threshold which the virtual machine will check against after each run of the garbage collector in the memory pool.

Specified by:

setCollectionUsageThreshold in interface java.lang.management.MemoryPoolMXBean

Parameters:

threshold - the size of the new collection usage threshold expressed in bytes.

setUsageThreshold

public void setUsageThreshold(long threshold)

Description copied from interface: java.lang.management.MemoryPoolMXBean

Updates this memory pool to have a new value for its usage threshold. Only values of zero or greater should be supplied. A zero value effectively turns off any further checking of memory usage by the virtual machine. A value greater than zero establishes the new threshold which the virtual machine will check against.

Specified by:

setUsageThreshold in interface java.lang.management.MemoryPoolMXBean

Parameters:

threshold - the size of the new usage threshold expressed in bytes.