org.aksw.commons.collections
Class MultiMaps

java.lang.Object
  org.aksw.commons.collections.MultiMaps

public class MultiMaps
extends Object

Created by Claus Stadler Date: Oct 9, 2010 Time: 5:42:34 PM A set of static methods for treating a Map> as a multimap (or rather graphs, as keys may be mapped to an empty set of values)

Constructor Summary

MultiMaps()

Method Summary

static <K,V> void	addAllKeys(Map<K,Set<V>> map, Iterable<K> keys)
static <K,V> Set<V>	addKey(Map<K,Set<V>> map, K key)
static <K,V> boolean	containsEntry(Map<K,Set<V>> map, K key, V value)
static <K,V> Map<K,Set<V>>	copy(Map<K,Set<V>> source)
static <T> Set<T>	getCommonParent(Map<T,? extends Collection<T>> map, T a, T b) Find the nearest set of nodes that are parents of both given nodes.
static <K,V> void	put(Map<K,Set<V>> map, K key, V value)
static <K,V> void	putAll(Map<K,Set<V>> map, K key, Collection<? extends V> vs)
static <K,V> void	putAll(Map<K,Set<V>> target, Map<? extends K,? extends Set<? extends V>> source)
static <K,V> Map<V,Set<K>>	reverse(Map<K,Set<V>> source) Creates a new map that is the reverse of the source
static <K,V> Set<V>	safeGet(Map<K,? extends Collection<V>> map, Object key) This method returns an empty set (Collections.emptySet) for keys that are not in the map.
static <K,V> Set<V>	safeGetAll(Map<K,? extends Collection<V>> map, Collection<?> keys) Returns the set of successors for a given set of keys
static <K,V> Collection<V>	safeGetC(Map<K,? extends Collection<V>> map, Object key) TODO Add to collection utils
static <T> Map<T,Set<T>>	transitiveClosure(Map<T,Set<T>> map)
static <T> Map<T,Set<T>>	transitiveClosure(Map<T,Set<T>> map, boolean inPlace)
static <T> Map<T,Set<T>>	transitiveClosureInPlace(Map<T,Set<T>> map)
static <T> Set<T>	transitiveGet(Map<T,? extends Collection<T>> map, Object key)
static <K,V> Collection<V>	values(Map<K,Set<V>> map)

Methods inherited from class java.lang.Object

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

Constructor Detail

MultiMaps

public MultiMaps()

Method Detail

putAll

public static <K,V> void putAll(Map<K,Set<V>> target,
                                Map<? extends K,? extends Set<? extends V>> source)

putAll

public static <K,V> void putAll(Map<K,Set<V>> map,
                                K key,
                                Collection<? extends V> vs)

put

public static <K,V> void put(Map<K,Set<V>> map,
                             K key,
                             V value)

containsEntry

public static <K,V> boolean containsEntry(Map<K,Set<V>> map,
                                          K key,
                                          V value)

values

public static <K,V> Collection<V> values(Map<K,Set<V>> map)

addKey

public static <K,V> Set<V> addKey(Map<K,Set<V>> map,
                                  K key)

addAllKeys

public static <K,V> void addAllKeys(Map<K,Set<V>> map,
                                    Iterable<K> keys)

copy

public static <K,V> Map<K,Set<V>> copy(Map<K,Set<V>> source)

reverse

public static <K,V> Map<V,Set<K>> reverse(Map<K,Set<V>> source)

Creates a new map that is the reverse of the source

Type Parameters:

K -

V -

Parameters:

source -

Returns:

safeGet

public static <K,V> Set<V> safeGet(Map<K,? extends Collection<V>> map,
                                   Object key)

This method returns an empty set (Collections.emptySet) for keys that are not in the map.

Type Parameters:

K -

V -

Parameters:

map -

key -

Returns:

safeGetAll

public static <K,V> Set<V> safeGetAll(Map<K,? extends Collection<V>> map,
                                      Collection<?> keys)

Returns the set of successors for a given set of keys

Type Parameters:

K -

V -

Parameters:

map -

keys -

Returns:

safeGetC

public static <K,V> Collection<V> safeGetC(Map<K,? extends Collection<V>> map,
                                           Object key)

TODO Add to collection utils

Type Parameters:

K -

V -

Parameters:

map -

key -

Returns:

transitiveGet

public static <T> Set<T> transitiveGet(Map<T,? extends Collection<T>> map,
                                       Object key)

transitiveClosure

public static <T> Map<T,Set<T>> transitiveClosure(Map<T,Set<T>> map)

transitiveClosure

public static <T> Map<T,Set<T>> transitiveClosure(Map<T,Set<T>> map,
                                                  boolean inPlace)

transitiveClosureInPlace

public static <T> Map<T,Set<T>> transitiveClosureInPlace(Map<T,Set<T>> map)

getCommonParent

public static <T> Set<T> getCommonParent(Map<T,? extends Collection<T>> map,
                                         T a,
                                         T b)

Find the nearest set of nodes that are parents of both given nodes.

Parameters:

map - A mapping from children to parents

a -

b -