com.force.i18n.commons.util.collection

Class IntHashSet

java.lang.Object

com.force.i18n.commons.util.collection.AbstractIntSet

com.force.i18n.commons.util.collection.IntHashSet

All Implemented Interfaces:

IntSet, Serializable

@Beta
public class IntHashSet
extends AbstractIntSet
implements Serializable

This class implements the IntSet interface, backed by a hash table (actually a IntHashMap instance). It makes no guarantees as to the iteration order of the set; in particular, it does not guarantee that the order will remain constant over time.

This class offers constant time performance for the basic operations (add, remove, contains and size), assuming the hash function disperses the elements properly among the buckets. Iterating over this set requires time proportional to the sum of the IntHashSet instance's size (the number of elements) plus the "capacity" of the backing IntHashMap instance (the number of buckets). Thus, it's very important not to set the intial capacity too high (or the load factor too low) if iteration performance is important.

Note that this implementation is not synchronized. If multiple threads access a set concurrently, and at least one of the threads modifies the set, it must be synchronized externally. Beta class. Classes under com.force.i18n.commons package will be moved into a dedicated project.

Author:

Based on Sun's java.util.HashSet (modified by koliver)

See Also:

IntSet, IntHashMap, IntMap, Serialized Form

Constructor Summary

Constructors

Constructor and Description
IntHashSet() Constructs a new, empty set; the backing HashMap instance has default capacity and load factor, which is 0.75.
IntHashSet(int initialCapacity) Constructs a new, empty set; the backing HashMap instance has the specified initial capacity and default load factor, which is 0.75.
IntHashSet(int initialCapacity, float loadFactor) Constructs a new, empty set; the backing HashMap instance has the specified initial capacity and the specified load factor.

Method Summary

Modifier and Type	Method and Description
boolean	add(int o) Adds the specified element to this set if it is not already present.
void	clear() Removes all of the elements from this set.
boolean	contains(int o) Returns true if this set contains the specified element.
IntIterator	iterator() Returns an iterator over the elements in this set.
IntSet	makeEmpty() Create a new empty IntSet with the same impl
boolean	remove(int o) Removes the given element from this set if it is present.
int	size() Returns the number of elements in this set (its cardinality).

Methods inherited from class com.force.i18n.commons.util.collection.AbstractIntSet

containsAll, equals, hashCode, isEmpty, toArray

Methods inherited from class java.lang.Object

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

Constructor Detail

IntHashSet

public IntHashSet()

Constructs a new, empty set; the backing HashMap instance has default capacity and load factor, which is 0.75.

IntHashSet

public IntHashSet(int initialCapacity,
                  float loadFactor)

Constructs a new, empty set; the backing HashMap instance has the specified initial capacity and the specified load factor.

Parameters:

initialCapacity - the initial capacity of the hash map.

loadFactor - the load factor of the hash map.

Throws:

IllegalArgumentException - if the initial capacity is less than zero, or if the load factor is nonpositive.

IntHashSet

public IntHashSet(int initialCapacity)

Constructs a new, empty set; the backing HashMap instance has the specified initial capacity and default load factor, which is 0.75.

Parameters:

initialCapacity - the initial capacity of the hash table.

Throws:

IllegalArgumentException - if the initial capacity is less than zero.

Method Detail

makeEmpty

public IntSet makeEmpty()

Description copied from interface: IntSet

Create a new empty IntSet with the same impl

Specified by:

makeEmpty in interface IntSet

Returns:

a new empty IntSet

iterator

public IntIterator iterator()

Description copied from interface: IntSet

Returns an iterator over the elements in this set. The elements are returned in no particular order (unless this set is an instance of some class that provides a guarantee).

Specified by:

iterator in interface IntSet

Returns:

an iterator over the elements in this set.

size

public int size()

Returns the number of elements in this set (its cardinality).

Specified by:

size in interface IntSet

Returns:

the number of elements in this set (its cardinality).

contains

public boolean contains(int o)

Returns true if this set contains the specified element.

Specified by:

contains in interface IntSet

Overrides:

contains in class AbstractIntSet

Parameters:

o - element whose presence in this set is to be tested.

Returns:

true if this set contains the specified element.

add

public boolean add(int o)

Adds the specified element to this set if it is not already present.

Specified by:

add in interface IntSet

Overrides:

add in class AbstractIntSet

Parameters:

o - element to be added to this set.

Returns:

true if the set did not already contain the specified element.

remove

public boolean remove(int o)

Removes the given element from this set if it is present.

Specified by:

remove in interface IntSet

Parameters:

o - object to be removed from this set, if present.

Returns:

true if the set contained the specified element.

clear

public void clear()

Removes all of the elements from this set.

Specified by:

clear in interface IntSet