@Exported public class GcInfo extends Object implements 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.
 
CompositeData
 with attributes as specified in the from method.| Modifier and Type | Method and Description | 
|---|---|
| boolean | containsKey(String key)Returns true if and only if this CompositeData instance contains
 an item whose name is key. | 
| boolean | containsValue(Object value)Returns true if and only if this CompositeData instance contains an item
 whose value is value. | 
| boolean | equals(Object obj)Indicates whether some other object is "equal to" this one. | 
| static GcInfo | from(CompositeData cd)Returns a GcInfo object represented by the
 given CompositeData. | 
| Object | get(String key)Returns the value of the item whose name is key. | 
| Object[] | getAll(String[] keys)Returns an array of the values of the items whose names are specified by keys, in the same order as keys. | 
| CompositeType | getCompositeType()Returns the composite type  of this composite data instance. | 
| 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()Returns a hash code value for the object. | 
| CompositeData | toCompositeData(CompositeType ct)Return the  CompositeDatarepresentation of thisGcInfo, including any GC-specific attributes. | 
| String | toString()Returns a string representation of the object. | 
| Collection | values()Returns an unmodifiable Collection view of the item values contained in this CompositeData instance. | 
public long getId()
public long getStartTime()
public long getEndTime()
public long getDuration()
public Map<String,MemoryUsage> getMemoryUsageBeforeGc()
public Map<String,MemoryUsage> getMemoryUsageAfterGc()
public static GcInfo from(CompositeData cd)
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 
IllegalArgumentException - if cd does not
   represent a GcInfo object with the attributes
   described above.public boolean containsKey(String key)
javax.management.openmbean.CompositeDatacontainsKey in interface CompositeDatakey - the key to be tested.public boolean containsValue(Object value)
javax.management.openmbean.CompositeDatacontainsValue in interface CompositeDatavalue - the value to be tested.public boolean equals(Object obj)
java.lang.Object
 The equals method implements an equivalence relation
 on non-null object references:
 
x, x.equals(x) should return
     true.
 x and y, x.equals(y)
     should return true if and only if
     y.equals(x) returns true.
 x, y, and z, if
     x.equals(y) returns true and
     y.equals(z) returns true, then
     x.equals(z) should return true.
 x and y, multiple invocations of
     x.equals(y) consistently return true
     or consistently return false, provided no
     information used in equals comparisons on the
     objects is modified.
 x,
     x.equals(null) should return false.
 
 The equals method for class Object implements
 the most discriminating possible equivalence relation on objects;
 that is, for any non-null reference values x and
 y, this method returns true if and only
 if x and y refer to the same object
 (x == y has the value true).
 
 Note that it is generally necessary to override the hashCode
 method whenever this method is overridden, so as to maintain the
 general contract for the hashCode method, which states
 that equal objects must have equal hash codes.
equals in interface CompositeDataequals in class Objectobj - the reference object with which to compare.true if this object is the same as the obj
          argument; false otherwise.Object.hashCode(), 
HashMappublic Object get(String key)
javax.management.openmbean.CompositeDataget in interface CompositeDatakey - the name of the item.public Object[] getAll(String[] keys)
javax.management.openmbean.CompositeDatagetAll in interface CompositeDatakeys - the names of the items.public CompositeType getCompositeType()
javax.management.openmbean.CompositeDatagetCompositeType in interface CompositeDatapublic int hashCode()
java.lang.ObjectHashMap.
 
 The general contract of hashCode is:
 
hashCode method
     must consistently return the same integer, provided no information
     used in equals comparisons on the object is modified.
     This integer need not remain consistent from one execution of an
     application to another execution of the same application.
 equals(Object)
     method, then calling the hashCode method on each of
     the two objects must produce the same integer result.
 Object.equals(java.lang.Object)
     method, then calling the hashCode method on each of the
     two objects must produce distinct integer results.  However, the
     programmer should be aware that producing distinct integer results
     for unequal objects may improve the performance of hash tables.
 
 As much as is reasonably practical, the hashCode method defined by
 class Object does return distinct integers for distinct
 objects. (This is typically implemented by converting the internal
 address of the object into an integer, but this implementation
 technique is not required by the
 Java™ programming language.)
hashCode in interface CompositeDatahashCode in class ObjectObject.equals(java.lang.Object), 
System.identityHashCode(java.lang.Object)public String toString()
java.lang.ObjecttoString method returns a string that
 "textually represents" this object. The result should
 be a concise but informative representation that is easy for a
 person to read.
 It is recommended that all subclasses override this method.
 
 The toString method for class Object
 returns a string consisting of the name of the class of which the
 object is an instance, the at-sign character `@', and
 the unsigned hexadecimal representation of the hash code of the
 object. In other words, this method returns a string equal to the
 value of:
 
getClass().getName() + '@' + Integer.toHexString(hashCode())
toString in interface CompositeDatatoString in class Objectpublic Collection values()
javax.management.openmbean.CompositeDatavalues in interface CompositeDatapublic 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.
toCompositeData in interface CompositeDataViewct - the CompositeType that the caller expects.
 This parameter is ignored and can be null.CompositeData representation.
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