org.codehaus.plexus.util
Constructor and Description |
---|
CollectionUtils() |
Modifier and Type | Method and Description |
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static Map |
getCardinalityMap(Collection col)
Returns a
Map mapping each unique element in
the given Collection to an Integer
representing the number of occurances of that element
in the Collection . |
static Collection |
intersection(Collection a,
Collection b)
Returns a
Collection containing the intersection
of the given Collection s. |
static List |
iteratorToList(Iterator it) |
static Map |
mergeMaps(Map[] maps)
Take a series of
Map s and merge
them where the ordering of the array from 0..n
is the dominant order. |
static Map |
mergeMaps(Map dominantMap,
Map recessiveMap)
Take a dominant and recessive Map and merge the key:value
pairs where the recessive Map may add key:value pairs to the dominant
Map but may not override any existing key:value pairs.
|
static Collection |
subtract(Collection a,
Collection b)
Returns a
Collection containing a - b. |
public static Map mergeMaps(Map dominantMap, Map recessiveMap)
dominantMap
- Dominant Map.recessiveMap
- Recessive Map.public static Map mergeMaps(Map[] maps)
Map
s and merge
them where the ordering of the array from 0..n
is the dominant order.maps
- An array of Maps to merge.public static Collection intersection(Collection a, Collection b)
Collection
containing the intersection
of the given Collection
s.
The cardinality of each element in the returned Collection
will be equal to the minimum of the cardinality of that element
in the two given Collection
s.
public static Collection subtract(Collection a, Collection b)
Collection
containing a - b.
The cardinality of each element e in the returned Collection
will be the cardinality of e in a minus the cardinality
of e in b, or zero, whichever is greater.public static Map getCardinalityMap(Collection col)
Map
mapping each unique element in
the given Collection
to an Integer
representing the number of occurances of that element
in the Collection
.
An entry that maps to null indicates that the
element does not appear in the given Collection
.