com.sun.management
Class GcInfo

java.lang.Object
  com.sun.management.GcInfo

All Implemented Interfaces:

CompositeData, CompositeDataView

public class GcInfo
extends Object
implements CompositeData, CompositeDataView

Garbage collection information. It contains the following information for one garbage collection as well as GC-specific attributes:

• Start time
• End time
• Duration
• Memory usage before the collection starts
• Memory usage after the collection ends

GcInfo is a CompositeData The GC-specific attributes can be obtained via the CompositeData interface. This is a historical relic, and other classes should not copy this pattern. Use CompositeDataView instead.

MXBean Mapping

GcInfo is mapped to a CompositeData with attributes as specified in the from method.

Since:

1.5

Method Summary

boolean	containsKey(String key)
boolean	containsValue(Object value)
boolean	equals(Object obj)
static GcInfo	from(CompositeData cd) Returns a GcInfo object represented by the given CompositeData.
Object	get(String key)
Object[]	getAll(String[] keys)
CompositeType	getCompositeType()
long	getDuration() Returns the elapsed time of this GC in milliseconds.
long	getEndTime() Returns the end time of this GC in milliseconds since the Java virtual machine was started.
long	getId() Returns the identifier of this garbage collection which is the number of collections that this collector has done.
Map<String,MemoryUsage>	getMemoryUsageAfterGc() Returns the memory usage of all memory pools at the end of this GC.
Map<String,MemoryUsage>	getMemoryUsageBeforeGc() Returns the memory usage of all memory pools at the beginning of this GC.
long	getStartTime() Returns the start time of this GC in milliseconds since the Java virtual machine was started.
int	hashCode()
CompositeData	toCompositeData(CompositeType ct) Return the CompositeData representation of this GcInfo, including any GC-specific attributes.
String	toString()
Collection	values()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Method Detail

getId

public long getId()

Returns the identifier of this garbage collection which is the number of collections that this collector has done.

Returns:

the identifier of this garbage collection which is the number of collections that this collector has done.

getStartTime

public long getStartTime()

Returns the start time of this GC in milliseconds since the Java virtual machine was started.

Returns:

the start time of this GC.

getEndTime

public long getEndTime()

Returns the end time of this GC in milliseconds since the Java virtual machine was started.

Returns:

the end time of this GC.

getDuration

public long getDuration()

Returns the elapsed time of this GC in milliseconds.

Returns:

the elapsed time of this GC in milliseconds.

getMemoryUsageBeforeGc

public Map<String,MemoryUsage> getMemoryUsageBeforeGc()

Returns the memory usage of all memory pools at the beginning of this GC. This method returns a Map of the name of a memory pool to the memory usage of the corresponding memory pool before GC starts.

Returns:

a Map of memory pool names to the memory usage of a memory pool before GC starts.

getMemoryUsageAfterGc

public Map<String,MemoryUsage> getMemoryUsageAfterGc()

Returns the memory usage of all memory pools at the end of this GC. This method returns a Map of the name of a memory pool to the memory usage of the corresponding memory pool when GC finishes.

Returns:

a Map of memory pool names to the memory usage of a memory pool when GC finishes.

from

public static GcInfo from(CompositeData cd)

Returns a GcInfo object represented by the given CompositeData. The given CompositeData must contain all the following attributes:

Attribute Name	Type
index	java.lang.Long
startTime	java.lang.Long
endTime	java.lang.Long
memoryUsageBeforeGc	javax.management.openmbean.TabularData
memoryUsageAfterGc	javax.management.openmbean.TabularData

Returns:

a GcInfo object represented by cd if cd is not null; null otherwise.

Throws:

IllegalArgumentException - if cd does not represent a GcInfo object with the attributes described above.

containsKey

public boolean containsKey(String key)

Specified by:

containsKey in interface CompositeData

containsValue

public boolean containsValue(Object value)

Specified by:

containsValue in interface CompositeData

equals

public boolean equals(Object obj)

Specified by:

equals in interface CompositeData

Overrides:

equals in class Object

get

public Object get(String key)

Specified by:

get in interface CompositeData

getAll

public Object[] getAll(String[] keys)

Specified by:

getAll in interface CompositeData

getCompositeType

public CompositeType getCompositeType()

Specified by:

getCompositeType in interface CompositeData

hashCode

public int hashCode()

Specified by:

hashCode in interface CompositeData

Overrides:

hashCode in class Object

toString

public String toString()

Specified by:

toString in interface CompositeData

Overrides:

toString in class Object

values

public Collection values()

Specified by:

values in interface CompositeData

toCompositeData

public CompositeData toCompositeData(CompositeType ct)

Return the CompositeData representation of this GcInfo, including any GC-specific attributes. The returned value will have at least all the attributes described in the from method, plus optionally other attributes.

Specified by:

toCompositeData in interface CompositeDataView

Parameters:

ct - the CompositeType that the caller expects. This parameter is ignored and can be null.

Returns:

the CompositeData representation.