public class PatriciaTrie<K,V>
extends java.util.AbstractMap<K,V>
implements java.io.Serializable
TrieA PATRICIA Trie is a compressed Trie. Instead of storing
 all data at the edges of the Trie (and having empty internal nodes),
 PATRICIA stores data in every node. This allows for very efficient traversal,
 insert, delete, predecessor, successor, prefix, range, and select(Object)
 operations. All operations are performed at worst in O(K) time, where K
 is the number of bits in the largest item in the tree. In practice,
 operations actually take O(A(K)) time, where A(K) is the average number of
 bits of all items in the tree.
 
Most importantly, PATRICIA requires very few comparisons to keys while doing any operation. While performing a lookup, each comparison (at most K of them, described above) will perform a single bit comparison against the given key, instead of comparing the entire key to another key.
The Trie can return operations in lexicographical order using the
 traverse(Cursor), 'prefix', 'submap', or 'iterator' methods. The
 Trie can also scan for items that are 'bitwise' (using an XOR
 metric) by the 'select' method. Bitwise closeness is determined by the
 KeyAnalyzer returning true or false for a bit being set or not in
 a given key.
 
Any methods here that take an Object argument may throw a
 ClassCastException if the method is expecting an instance of K
 and it isn't K.
| Modifier and Type | Field and Description | 
|---|---|
| protected KeyAnalyzer<? super K> | keyAnalyzerThe  KeyAnalyzerthat's being used to build the
 PATRICIATrie | 
| Constructor and Description | 
|---|
| PatriciaTrie(KeyAnalyzer<? super K> keyAnalyzer) | 
| PatriciaTrie(KeyAnalyzer<? super K> keyAnalyzer,
            java.util.Map<? extends K,? extends V> m) | 
| Modifier and Type | Method and Description | 
|---|---|
| void | clear() | 
| java.util.Comparator<? super K> | comparator() | 
| boolean | containsKey(java.lang.Object k) | 
| java.util.Set<java.util.Map.Entry<K,V>> | entrySet() | 
| K | firstKey() | 
| V | get(java.lang.Object k) | 
| java.util.SortedMap<K,V> | headMap(K toKey) | 
| java.util.Set<K> | keySet() | 
| K | lastKey() | 
| java.util.SortedMap<K,V> | prefixMap(K prefix)Returns a view of this  Trieof all elements that are prefixed
 by the given key. | 
| V | put(K key,
   V value) | 
| V | remove(java.lang.Object k) | 
| java.util.Map.Entry<K,V> | select(K key)Returns the  Map.Entrywhose key is closest in a bitwise XOR
 metric to the given key. | 
| java.util.Map.Entry<K,V> | select(K key,
      Cursor<? super K,? super V> cursor)Iterates through the  Trie, starting with the entry whose bitwise
 value is closest in an XOR metric to the given key. | 
| K | selectKey(K key)Returns the key that is closest in a bitwise XOR metric to the
 provided key. | 
| V | selectValue(K key)Returns the value whose key is closest in a bitwise XOR metric to
 the provided key. | 
| int | size() | 
| java.util.SortedMap<K,V> | subMap(K fromKey,
      K toKey) | 
| java.util.SortedMap<K,V> | tailMap(K fromKey) | 
| java.lang.String | toString() | 
| java.util.Map.Entry<K,V> | traverse(Cursor<? super K,? super V> cursor)Traverses the  Triein lexicographical order. | 
| java.util.Collection<V> | values() | 
clone, containsValue, equals, hashCode, isEmpty, putAllprotected final KeyAnalyzer<? super K> keyAnalyzer
KeyAnalyzer that's being used to build the
 PATRICIA Triepublic PatriciaTrie(KeyAnalyzer<? super K> keyAnalyzer)
public PatriciaTrie(KeyAnalyzer<? super K> keyAnalyzer, java.util.Map<? extends K,? extends V> m)
public java.util.Comparator<? super K> comparator()
public java.util.SortedMap<K,V> prefixMap(K prefix)
TrieTrie of all elements that are prefixed
 by the given key.
 In a Trie with fixed size keys, this is essentially a
 Map.get(Object) operation.
 
For example, if the Trie contains 'Anna', 'Anael',
 'Analu', 'Andreas', 'Andrea', 'Andres', and 'Anatole', then
 a lookup of 'And' would return 'Andreas', 'Andrea', and 'Andres'.
public void clear()
clear in interface java.util.Map<K,V>clear in class java.util.AbstractMap<K,V>public int size()
size in interface java.util.Map<K,V>size in class java.util.AbstractMap<K,V>public V put(K key,
             V value)
put in interface java.util.Map<K,V>put in class java.util.AbstractMap<K,V>public V get(java.lang.Object k)
get in interface java.util.Map<K,V>get in class java.util.AbstractMap<K,V>public java.util.Map.Entry<K,V> select(K key)
TrieMap.Entry whose key is closest in a bitwise XOR
 metric to the given key. This is NOT lexicographic closeness.
 For example, given the keys:
 Trie contained 'H' and 'L', a lookup of 'D' would
 return 'L', because the XOR distance between D & L is smaller
 than the XOR distance between D & H.Map.Entry whose key is closest in a bitwise XOR metric
 to the provided key.public java.util.Map.Entry<K,V> select(K key,
                                       Cursor<? super K,? super V> cursor)
TrieTrie, starting with the entry whose bitwise
 value is closest in an XOR metric to the given key. After the closest
 entry is found, the Trie will call select on that entry and continue
 calling select for each entry (traversing in order of XOR closeness,
 NOT lexicographically) until the cursor returns Cursor.Decision.EXIT.
 The cursor can return Cursor.Decision.CONTINUE to continue traversing.
 
Cursor.Decision.REMOVE_AND_EXIT is used to remove the current element
 and stop traversing.
 
Note: The Cursor.Decision.REMOVE operation is not supported.
Cursor.Decision.EXIT on, or null
 if it continued till the end.public java.util.Map.Entry<K,V> traverse(Cursor<? super K,? super V> cursor)
TrieTrie in lexicographical order.
 Cursor.select(java.util.Map.Entry) will be called on each entry.
 The traversal will stop when the cursor returns Cursor.Decision.EXIT,
 Cursor.Decision.CONTINUE is used to continue traversing and
 Cursor.Decision.REMOVE is used to remove the element that was selected
 and continue traversing.
 
Cursor.Decision.REMOVE_AND_EXIT is used to remove the current element
 and stop traversing.
Cursor.Decision.EXIT on, or null
 if it continued till the end.public boolean containsKey(java.lang.Object k)
containsKey in interface java.util.Map<K,V>containsKey in class java.util.AbstractMap<K,V>public java.util.Set<java.util.Map.Entry<K,V>> entrySet()
entrySet in interface java.util.Map<K,V>entrySet in interface java.util.SortedMap<K,V>entrySet in class java.util.AbstractMap<K,V>public java.util.Set<K> keySet()
keySet in interface java.util.Map<K,V>keySet in interface java.util.SortedMap<K,V>keySet in class java.util.AbstractMap<K,V>public java.util.Collection<V> values()
values in interface java.util.Map<K,V>values in interface java.util.SortedMap<K,V>values in class java.util.AbstractMap<K,V>public V remove(java.lang.Object k)
remove in interface java.util.Map<K,V>remove in class java.util.AbstractMap<K,V>java.lang.ClassCastException - if provided key is of an incompatible typepublic K selectKey(K key)
TrieTrie contained 'H' and 'L', a lookup of 'D' would
 return 'L', because the XOR distance between D & L is smaller
 than the XOR distance between D & H.public V selectValue(K key)
TrieTrie contained 'H' and 'L', a lookup of 'D' would
 return 'L', because the XOR distance between D & L is smaller
 than the XOR distance between D & H.selectValue in interface Trie<K,V>public java.lang.String toString()
toString in class java.util.AbstractMap<K,V>Copyright © 2018 The Apache Software Foundation