Class GcInfo
- All Implemented Interfaces:
CompositeData
,CompositeDataView
- 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
Modifier and TypeMethodDescriptionboolean
containsKey
(String key) Returnstrue
if and only if thisCompositeData
instance contains an item whose name iskey
.boolean
containsValue
(Object value) Returnstrue
if and only if thisCompositeData
instance contains an item whose value isvalue
.boolean
Compares the specified obj parameter with thisCompositeData
instance for equality.static GcInfo
from
(CompositeData cd) Returns aGcInfo
object represented by the givenCompositeData
.Returns the value of the item whose name iskey
.Object[]
Returns an array of the values of the items whose names are specified bykeys
, in the same order askeys
.Returns the composite type of this composite data instance.long
Returns the elapsed time of this GC in milliseconds.long
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.Returns the memory usage of all memory pools at the end of this GC.Returns the memory usage of all memory pools at the beginning of this GC.long
Returns the start time of this GC in milliseconds since the Java virtual machine was started.int
hashCode()
Returns the hash code value for thisCompositeData
instance.Return theCompositeData
representation of thisGcInfo
, including any GC-specific attributes.toString()
Returns a string representation of thisCompositeData
instance.Collection
<?> values()
Returns an unmodifiable Collection view of the item values contained in thisCompositeData
instance.
-
Method Details
-
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
Returns the memory usage of all memory pools at the beginning of this GC. This method returns aMap
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
Returns the memory usage of all memory pools at the end of this GC. This method returns aMap
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
Returns aGcInfo
object represented by the givenCompositeData
. The givenCompositeData
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 bycd
ifcd
is notnull
;null
otherwise. - Throws:
IllegalArgumentException
- ifcd
does not represent aGcInfo
object with the attributes described above.
-
containsKey
Description copied from interface:CompositeData
Returnstrue
if and only if thisCompositeData
instance contains an item whose name iskey
. Ifkey
is a null or empty String, this method simply returns false.- Specified by:
containsKey
in interfaceCompositeData
- Parameters:
key
- the key to be tested.- Returns:
- true if this
CompositeData
contains the key.
-
containsValue
Description copied from interface:CompositeData
Returnstrue
if and only if thisCompositeData
instance contains an item whose value isvalue
.- Specified by:
containsValue
in interfaceCompositeData
- Parameters:
value
- the value to be tested.- Returns:
- true if this
CompositeData
contains the value.
-
equals
Description copied from interface:CompositeData
Compares the specified obj parameter with thisCompositeData
instance for equality.Returns
true
if and only if all of the following statements are true:- obj is non null,
- obj also implements the
CompositeData
interface, - their composite types are equal
- their contents, i.e. (name, value) pairs are equal. If a value contained in
the content is an array, the value comparison is done as if by calling
the
deepEquals
method for arrays of object reference types or the appropriate overloading ofArrays.equals(e1,e2)
for arrays of primitive types
This ensures that this
equals
method works properly for obj parameters which are different implementations of theCompositeData
interface, with the restrictions mentioned in theequals
method of thejava.util.Collection
interface.- Specified by:
equals
in interfaceCompositeData
- Overrides:
equals
in classObject
- Parameters:
obj
- the object to be compared for equality with thisCompositeData
instance.- Returns:
true
if the specified object is equal to thisCompositeData
instance.- See Also:
-
get
Description copied from interface:CompositeData
Returns the value of the item whose name iskey
.- Specified by:
get
in interfaceCompositeData
- Parameters:
key
- the name of the item.- Returns:
- the value associated with this key.
-
getAll
Description copied from interface:CompositeData
Returns an array of the values of the items whose names are specified bykeys
, in the same order askeys
.- Specified by:
getAll
in interfaceCompositeData
- Parameters:
keys
- the names of the items.- Returns:
- the values corresponding to the keys.
-
getCompositeType
Description copied from interface:CompositeData
Returns the composite type of this composite data instance.- Specified by:
getCompositeType
in interfaceCompositeData
- Returns:
- the type of this CompositeData.
-
hashCode
public int hashCode()Description copied from interface:CompositeData
Returns the hash code value for thisCompositeData
instance.The hash code of a
CompositeData
instance is the sum of the hash codes of all elements of information used inequals
comparisons (ie: its composite type and all the item values).This ensures that
t1.equals(t2)
implies thatt1.hashCode()==t2.hashCode()
for any twoCompositeData
instancest1
andt2
, as required by the general contract of the methodObject.hashCode()
.Each item value's hash code is added to the returned hash code. If an item value is an array, its hash code is obtained as if by calling the
deepHashCode
method for arrays of object reference types or the appropriate overloading ofArrays.hashCode(e)
for arrays of primitive types.- Specified by:
hashCode
in interfaceCompositeData
- Overrides:
hashCode
in classObject
- Returns:
- the hash code value for this
CompositeData
instance - See Also:
-
toString
Description copied from interface:CompositeData
Returns a string representation of thisCompositeData
instance.The string representation consists of the name of the implementing class, the string representation of the composite type of this instance, and the string representation of the contents (ie list the itemName=itemValue mappings).
- Specified by:
toString
in interfaceCompositeData
- Overrides:
toString
in classObject
- Returns:
- a string representation of this
CompositeData
instance
-
values
Description copied from interface:CompositeData
Returns an unmodifiable Collection view of the item values contained in thisCompositeData
instance. The returned collection's iterator will return the values in the ascending lexicographic order of the corresponding item names.- Specified by:
values
in interfaceCompositeData
- Returns:
- the values.
-
toCompositeData
Return theCompositeData
representation of thisGcInfo
, including any GC-specific attributes. The returned value will have at least all the attributes described in thefrom
method, plus optionally other attributes.- Specified by:
toCompositeData
in interfaceCompositeDataView
- Parameters:
ct
- theCompositeType
that the caller expects. This parameter is ignored and can be null.- Returns:
- the
CompositeData
representation.
-