Package com.yetnt.utils.collection

Class HashMultiMap<K,T>

java.lang.Object

java.util.AbstractMap<K,ArrayList<T>>

java.util.HashMap<K,ArrayList<T>>

com.yetnt.utils.collection.HashMultiMap<K,T>

Type Parameters:

K - the type of keys maintained by this multimap

T - the type stored in the list

All Implemented Interfaces:

Serializable, Cloneable, Map<K,ArrayList<T>>

public class HashMultiMap<K,T>
extends HashMap<K,ArrayList<T>>

A HashMap who maps 1 key to multiple values.

This class provides methods like putValue(Object, Object) to add a single value to the collection of values associated with a key, and getValues(Object) to retrieve all values for a given key.

From Jaiva VSCode Extension

Author:

Lehlogonolo Poole

See Also:

• Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class java.util.AbstractMap

AbstractMap.SimpleEntry<K,V>, AbstractMap.SimpleImmutableEntry<K,V>

Nested classes/interfaces inherited from interface java.util.Map

Map.Entry<K,V>

Constructor Summary

Constructors

Constructor	Description
HashMultiMap()

Method Summary

Modifier and Type	Method	Description
K	findFirstKeyWhere(Predicate<ArrayList<T>> test)
ArrayList<T>	getValues(K key)	Retrieves the list of values associated with the specified key.
boolean	holdsSingletonLists()
void	putValue(K key, T value)	Adds a value to the list of values associated with the specified key.

Methods inherited from class java.util.HashMap

clear, clone, compute, computeIfAbsent, computeIfPresent, containsKey, containsValue, entrySet, forEach, get, getOrDefault, isEmpty, keySet, merge, newHashMap, put, putAll, putIfAbsent, remove, remove, replace, replace, replaceAll, size, values

Methods inherited from class java.util.AbstractMap

equals, hashCode, toString

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Map

equals, hashCode

Constructor Details

HashMultiMap

public HashMultiMap()

Method Details

putValue

public void putValue(K key,
 T value)

Adds a value to the list of values associated with the specified key. If the key does not already exist in the map, a new list is created for it.

Parameters:

key - The key to which the value should be added.

value - The value to add to the list associated with the key.

getValues

public ArrayList<T> getValues(K key)

Retrieves the list of values associated with the specified key.

Parameters:

key - The key whose associated values are to be returned.

Returns:

The list of values associated with the specified key, or null if the key does not exist in the map.

holdsSingletonLists

public boolean holdsSingletonLists()

findFirstKeyWhere

public K findFirstKeyWhere(Predicate<ArrayList<T>> test)