it.unimi.dsi.util.TernaryIntervalSearchTree

All Implemented Interfaces:: Function<CharSequence,Long>, Object2LongFunction<CharSequence>, PrefixMap<MutableString>, StringMap<MutableString>, Serializable, Function<CharSequence,Long>, ToLongFunction<CharSequence>

public class TernaryIntervalSearchTree
extends AbstractPrefixMap
implements Serializable

Ternary interval search trees.

Ternary search trees are a data structure used to store words over an alphabet; they are a useful alternatives to tries when the alphabet is large.

Ternary interval search trees have the additional properties of being able to locate quickly intervals of words extending a given prefix (where “quickly” means that no more successful character comparisons than the prefix length are performed). They do so by storing at each node the number of words covered by that node.

This implementation exposes a number of interfaces: in particular, the set of words is seen as a lexicographically ordered ObjectList.

This class is mutable, but for the time it implements only add(CharSequence). Words cannot be removed.

See Also:: Serialized Form

Field Summary

Fields inherited from class it.unimi.dsi.util.AbstractPrefixMap
list, prefixMap, rangeMap

Fields inherited from class it.unimi.dsi.fastutil.objects.AbstractObject2LongFunction
defRetValue

Constructor Summary

Constructors
Constructor	Description
`TernaryIntervalSearchTree()`	Creates a new empty ternary search tree.
`TernaryIntervalSearchTree(Collection<? extends CharSequence> c)`	Creates a new empty ternary search tree and populates it with a given collection of character sequences.

Method Summary

Modifier and Type	Method	Description
`boolean`	`add(CharSequence s)`
`boolean`	`containsKey(Object o)`
`Interval`	`getApproximatedInterval(CharSequence s)`
`protected long`	`getIndex(CharSequence s)`
`protected Interval`	`getInterval(CharSequence s)`	Returns the range of strings having a given prefix.
`long`	`getLong(Object o)`
`protected MutableString`	`getTerm(int index, MutableString s)`	Writes a string specified by index into a `MutableString`.
`static void`	`main(String[] arg)`
`int`	`size()`

Methods inherited from class it.unimi.dsi.util.AbstractPrefixMap

list, prefixMap, rangeMap

Methods inherited from class it.unimi.dsi.fastutil.objects.AbstractObject2LongFunction

defaultReturnValue, defaultReturnValue

Methods inherited from class java.lang.Object

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

Methods inherited from interface it.unimi.dsi.fastutil.Function

apply, clear

Methods inherited from interface java.util.function.Function

andThen, compose

Methods inherited from interface it.unimi.dsi.fastutil.objects.Object2LongFunction

applyAsLong, defaultReturnValue, defaultReturnValue, get, put, put, remove, removeLong

Constructor Details
- TernaryIntervalSearchTree
  
  public TernaryIntervalSearchTree()
  
  Creates a new empty ternary search tree.
- TernaryIntervalSearchTree
  
  public TernaryIntervalSearchTree(Collection<? extends CharSequence> c)
  
  Creates a new empty ternary search tree and populates it with a given collection of character sequences.
  
  Parameters:
  
  c - a collection of character sequences.
Method Details
- getInterval
  
  protected Interval getInterval(CharSequence s)
  
  Description copied from class: AbstractPrefixMap
  
  Returns the range of strings having a given prefix.
  
  Specified by:
  
  getInterval in class AbstractPrefixMap
  
  Parameters:
  
  s - a prefix.
  
  Returns:
  
  the corresponding range of strings as an interval.
- getApproximatedInterval
  
  public Interval getApproximatedInterval(CharSequence s)
- getTerm
  
  protected MutableString getTerm(int index, MutableString s)
  
  Description copied from class: AbstractPrefixMap
  
  Writes a string specified by index into a MutableString.
  
  Specified by:
  
  getTerm in class AbstractPrefixMap
  
  Parameters:
  
  index - the index of a string.
  
  s - a mutable string.
  
  Returns:
  
  string.
- getIndex
  
  protected long getIndex(CharSequence s)
- containsKey
  
  public boolean containsKey(Object o)
  
  Specified by:
  
  containsKey in interface Function<CharSequence,Long>
- getLong
  
  public long getLong(Object o)
  
  Specified by:
  
  getLong in interface Object2LongFunction<CharSequence>
- add
  
  public boolean add(CharSequence s)
- size
  
  public int size()
  
  Specified by:
  
  size in interface Function<CharSequence,Long>
- main
  
  public static void main(String[] arg) throws IOException, JSAPException, NoSuchMethodException
  
  Throws:
  
  IOException
  
  JSAPException
  
  NoSuchMethodException

Class TernaryIntervalSearchTree

Field Summary

Fields inherited from class it.unimi.dsi.util.AbstractPrefixMap

Fields inherited from class it.unimi.dsi.fastutil.objects.AbstractObject2LongFunction