SSF.OS.NetFlow
Class ShrinkableHashMap

java.lang.Object
  |
  +--SSF.OS.NetFlow.ShrinkableHashMap

Direct Known Subclasses:

IpFlowTable

public class ShrinkableHashMap

extends java.lang.Object

User defined HashMap. It can shrink as well as grow dynamically according to the usage of memory

Constructor Summary

ShrinkableHashMap()
this default constructor should NOT be used

ShrinkableHashMap(int initialCapacity)
Constructor: the LoadFactor is always set to be 1.0 specify the intial capacity

ShrinkableHashMap(int initialCapacity, float upperFactor)
Constructor: specify the upperFactor and the initCapacity

ShrinkableHashMap(int initialCapacity, float upperFactor, float lowerFactor)
Constructor: to specify the lower bound factor, it is necessary to specify the upperLoad factor too so that compiler won't get confused

Method Summary

java.lang.Object	get(java.lang.Object key) Return the object of the given key notice that potentially an object list is returned
protected void	growRehash() enlarge the table size by 2 (plus 1)
void	put(java.lang.Object key, java.lang.Object Item) Put the object with given key in the map.
void	remove(java.lang.Object key) Remove the object corrsponding to the given key if the memory utilization is low enough, shrink
protected void	shrinkRehash() shrink the table size by half
java.util.Collection	values() Return a collection view of all the objects stored in the map

Methods inherited from class java.lang.Object

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

Constructor Detail

ShrinkableHashMap

public ShrinkableHashMap()

this default constructor should NOT be used

ShrinkableHashMap

public ShrinkableHashMap(int initialCapacity)

Constructor: the LoadFactor is always set to be 1.0 specify the intial capacity

ShrinkableHashMap

public ShrinkableHashMap(int initialCapacity,
                         float upperFactor)

Constructor: specify the upperFactor and the initCapacity

ShrinkableHashMap

public ShrinkableHashMap(int initialCapacity,
                         float upperFactor,
                         float lowerFactor)

Constructor: to specify the lower bound factor, it is necessary to specify the upperLoad factor too so that compiler won't get confused

Method Detail

shrinkRehash

protected void shrinkRehash()

shrink the table size by half

growRehash

protected void growRehash()

enlarge the table size by 2 (plus 1)

put

public void put(java.lang.Object key,
                java.lang.Object Item)

Put the object with given key in the map. "grow" in size if needed

get

public java.lang.Object get(java.lang.Object key)

Return the object of the given key notice that potentially an object list is returned

values

public java.util.Collection values()

Return a collection view of all the objects stored in the map

remove

public void remove(java.lang.Object key)

Remove the object corrsponding to the given key if the memory utilization is low enough, shrink