edu.ucla.sspace.util

Class TrieSet

java.lang.Object

java.util.AbstractCollection<E>

java.util.AbstractSet<String>

edu.ucla.sspace.util.TrieSet

All Implemented Interfaces:

Iterable<String>, Collection<String>, Set<String>

public class TrieSet
extends AbstractSet<String>

A space-efficient set of String instances. In addition to providing reduced space usage, testing for contains may offer increased performance over a HashMap of String instances due to not requiring the String.hashCode() to be computed.

This class is not synchronized. If concurrent updating behavior is required, the map should be wrapped using Collections.synchronizedSet(Set). This map will never throw a ConcurrentModificationException during iteration. The behavior is unspecified if the map is modified while an iterator is being used.

Author:

David Jurgens

Constructor Summary

Constructors

Constructor and Description
TrieSet() Creates an empty set of strings.
TrieSet(Collection<String> c) Creates a set of the strings contained in the collection.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	add(String s) 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(Object o) Returns true if this set contains the specified element.
boolean	isEmpty() Returns true if this set contains no elements.
Iterator<String>	iterator() Returns an iterator over the elements in this set.
boolean	remove(Object o) Removes the specified element from this set if it is present.
int	size() Returns the number of elements in this set.
String	toString()

Methods inherited from class java.util.AbstractSet

equals, hashCode, removeAll

Methods inherited from class java.util.AbstractCollection

addAll, containsAll, retainAll, toArray, toArray

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Set

addAll, containsAll, retainAll, toArray, toArray

Constructor Detail

TrieSet

public TrieSet()

Creates an empty set of strings.

TrieSet

public TrieSet(Collection<String> c)

Creates a set of the strings contained in the collection.

Method Detail

add

public boolean add(String s)

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

Specified by:

add in interface Collection<String>

Specified by:

add in interface Set<String>

Overrides:

add in class AbstractCollection<String>

clear

public void clear()

Removes all of the elements from this set.

Specified by:

clear in interface Collection<String>

Specified by:

clear in interface Set<String>

Overrides:

clear in class AbstractCollection<String>

contains

public boolean contains(Object o)

Returns true if this set contains the specified element.

Specified by:

contains in interface Collection<String>

Specified by:

contains in interface Set<String>

Overrides:

contains in class AbstractCollection<String>

isEmpty

public boolean isEmpty()

Returns true if this set contains no elements.

Specified by:

isEmpty in interface Collection<String>

Specified by:

isEmpty in interface Set<String>

Overrides:

isEmpty in class AbstractCollection<String>

iterator

public Iterator<String> iterator()

Returns an iterator over the elements in this set.

Specified by:

iterator in interface Iterable<String>

Specified by:

iterator in interface Collection<String>

Specified by:

iterator in interface Set<String>

Specified by:

iterator in class AbstractCollection<String>

remove

public boolean remove(Object o)

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

Specified by:

remove in interface Collection<String>

Specified by:

remove in interface Set<String>

Overrides:

remove in class AbstractCollection<String>

size

public int size()

Returns the number of elements in this set.

Specified by:

size in interface Collection<String>

Specified by:

size in interface Set<String>

Specified by:

size in class AbstractCollection<String>

toString

public String toString()

Overrides:

toString in class AbstractCollection<String>