jtp.util
Class ReplacementHashSet

java.lang.Object
  |
  +--java.util.AbstractCollection
        |
        +--java.util.AbstractSet
              |
              +--jtp.util.ReplacementHashSet

All Implemented Interfaces:

Collection, Set

public class ReplacementHashSet

extends AbstractSet

This is an implementation of set based on a simple replacement hash table. The table consists of a fixed number of slots. Each object added to the set is assigned a slot according to its hash code. If an attempt is made to add an object that belongs to the same slot as another object already in the table, the new object replaces the old; the old object is no longer in the set.

This set is not thread-safe. Also, the behavior of its iterator is undefined in case when the set is modified after the creation of iterator.

Constructor Summary

ReplacementHashSet(int capacity)

Method Summary

boolean	add(Object o)
boolean	contains(Object o)
int	getCapacity()
Object	getObjectAtSlot(int slot) returns the object in a given slot of the table
int	getSlot(Object o) calculates the slot number to assign to an object.
Iterator	iterator()
boolean	remove(Object o)
int	size()

Methods inherited from class java.util.AbstractSet

equals, hashCode, removeAll

Methods inherited from class java.util.AbstractCollection

addAll, clear, containsAll, isEmpty, retainAll, toArray, toArray, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Set

addAll, clear, containsAll, isEmpty, retainAll, toArray, toArray

Constructor Detail

ReplacementHashSet

public ReplacementHashSet(int capacity)

Method Detail

size

public int size()

Specified by:

size in interface Set

Specified by:

size in class AbstractCollection

iterator

public Iterator iterator()

Specified by:

iterator in interface Set

Specified by:

iterator in class AbstractCollection

contains

public boolean contains(Object o)

Specified by:

contains in interface Set

Overrides:

contains in class AbstractCollection

remove

public boolean remove(Object o)

Specified by:

remove in interface Set

Overrides:

remove in class AbstractCollection

add

public boolean add(Object o)

Specified by:

add in interface Set

Overrides:

add in class AbstractCollection

getSlot

public int getSlot(Object o)

calculates the slot number to assign to an object.

Parameters:

o - the object to assign to a slot.

Returns:

the slot number for the input object.

getCapacity

public int getCapacity()

getObjectAtSlot

public Object getObjectAtSlot(int slot)

returns the object in a given slot of the table

Returns:

the object in a given slot of the table