com.asakusafw.utils.collections

Class Maps

java.lang.Object

com.asakusafw.utils.collections.Maps

public final class Maps
extends Object

Utilities about Map.

Method Summary

Modifier and Type	Method and Description
static <K,V> void	addAllToList(Map<? super K,List<V>> map, Map<? extends K,? extends V> source) Adds the all values to the list which is in the map with the key.
static <K,V> void	addAllToSet(Map<? super K,Set<V>> map, Map<? extends K,? extends V> source) Adds the all values to the set which is in the map with the key.
static <K,V> void	addToList(Map<? super K,List<V>> map, K key, V value) Add the value to the list which is in the map with the key.
static <K,V> void	addToSet(Map<? super K,Set<V>> map, K key, V value) Add the value to the set which is in the map with the key.
static <K,V> Map<K,V>	create() Creates and returns an empty map.
static <K,V> Map<K,V>	freeze(Map<? extends K,? extends V> map) Returns a frozen map.
static <K,V> Map<K,V>	from(Map<? extends K,? extends V> map) Returns a copy of the map.
static <K,V> void	mergeAllIntoList(Map<? super K,List<V>> map, Map<? extends K,? extends Collection<? extends V>> source) Merges the all values into the list which is in the map with the key.
static <K,V> void	mergeAllIntoSet(Map<? super K,Set<V>> map, Map<? extends K,? extends Collection<? extends V>> source) Merges the all values into the set which is in the map with the key.
static <K,V> void	mergeIntoList(Map<? super K,List<V>> map, K key, Collection<? extends V> values) Merges the values into the list which is in the map with the key.
static <K,V> void	mergeIntoSet(Map<? super K,Set<V>> map, K key, Collection<? extends V> values) Merges the values into the set which is in the map with the key.
static <T> Map<T,T>	pairs(T... pairs) Returns a map whose key and value have same type.
static <K,V> Map<V,List<K>>	transpose(Map<? extends K,? extends V> map) Returns a transposed map.

Methods inherited from class java.lang.Object

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

Method Detail

create

public static <K,V> Map<K,V> create()

Creates and returns an empty map. The map is modifiable.

Type Parameters:

K - the key type

V - the value type

Returns:

created map

from

public static <K,V> Map<K,V> from(Map<? extends K,? extends V> map)

Returns a copy of the map. The returned map is modifiable.

Type Parameters:

K - the key type

V - the value type

Parameters:

map - target map

Returns:

created map

freeze

public static <K,V> Map<K,V> freeze(Map<? extends K,? extends V> map)

Returns a frozen map. The returned map is not modifiable.

Type Parameters:

K - the key type

V - the value type

Parameters:

map - target map

Returns:

created map

transpose

public static <K,V> Map<V,List<K>> transpose(Map<? extends K,? extends V> map)

Returns a transposed map. If the map contains duplicated value, the transposed map uses only one of them. The map is modifiable.

Type Parameters:

K - the key type

V - the value type

Parameters:

map - target map

Returns:

transposed map

pairs

@SafeVarargs
public static <T> Map<T,T> pairs(T... pairs)

Returns a map whose key and value have same type. The map is modifiable.

Type Parameters:

T - the key and value type

Parameters:

pairs - array contains key and value alternatively

Returns:

created map

addToList

public static <K,V> void addToList(Map<? super K,List<V>> map,
                                   K key,
                                   V value)

Add the value to the list which is in the map with the key. If the map does not contains the key, this first put a new list into the map.

Type Parameters:

K - the key type

V - the value type

Parameters:

map - target map

key - the key of target list

value - the value to add to target list

addAllToList

public static <K,V> void addAllToList(Map<? super K,List<V>> map,
                                      Map<? extends K,? extends V> source)

Adds the all values to the list which is in the map with the key. If the map does not contains the key, this first put a new list into the map.

Type Parameters:

K - the key type

V - the value type

Parameters:

map - target map

source - the source map

Since:

0.5.1

mergeIntoList

public static <K,V> void mergeIntoList(Map<? super K,List<V>> map,
                                       K key,
                                       Collection<? extends V> values)

Merges the values into the list which is in the map with the key. If the map does not contains the key, this first put a new list into the map.

Type Parameters:

K - the key type

V - the value type

Parameters:

map - target map

key - the key of target list

values - the values to merge into target list

Since:

0.5.1

mergeAllIntoList

public static <K,V> void mergeAllIntoList(Map<? super K,List<V>> map,
                                          Map<? extends K,? extends Collection<? extends V>> source)

Merges the all values into the list which is in the map with the key. If the map does not contains the key, this first put a new list into the map.

Type Parameters:

K - the key type

V - the value type

Parameters:

map - target map

source - the source map

Since:

0.5.1

addToSet

public static <K,V> void addToSet(Map<? super K,Set<V>> map,
                                  K key,
                                  V value)

Add the value to the set which is in the map with the key. If the map does not contains the key, this first put a new set into the map.

Type Parameters:

K - the key type

V - the value type

Parameters:

map - target map

key - the key of target list

value - the value to add to target list

addAllToSet

public static <K,V> void addAllToSet(Map<? super K,Set<V>> map,
                                     Map<? extends K,? extends V> source)

Adds the all values to the set which is in the map with the key. If the map does not contains the key, this first put a new set into the map.

Type Parameters:

K - the key type

V - the value type

Parameters:

map - target map

source - the source map

Since:

0.5.1

mergeIntoSet

public static <K,V> void mergeIntoSet(Map<? super K,Set<V>> map,
                                      K key,
                                      Collection<? extends V> values)

Merges the values into the set which is in the map with the key. If the map does not contains the key, this first put a new set into the map.

Type Parameters:

K - the key type

V - the value type

Parameters:

map - target map

key - the key of target set

values - the values to merge into target set

Since:

0.5.1

mergeAllIntoSet

public static <K,V> void mergeAllIntoSet(Map<? super K,Set<V>> map,
                                         Map<? extends K,? extends Collection<? extends V>> source)

Merges the all values into the set which is in the map with the key. If the map does not contains the key, this first put a new set into the map.

Type Parameters:

K - the key type

V - the value type

Parameters:

map - target map

source - the source map

Since:

0.5.1