MultiValueMap (AdroitLogic Project-X 17.01.2 API)

java.lang.Object
- org.adroitlogic.x.utils.MultiValueMap<K,V>

All Implemented Interfaces:

Map<K,List<V>>
```
public class MultiValueMap<K,V>
extends Object
implements Map<K,List<V>>
```
A Map implementation that could hold multiple duplicates for a given key. The implementation is efficient for the first level value manipulation and also exposes a flat single value map structure when necessary with least possible processing overhead.
While manipulating only first values or only duplicates is efficient, the value retrieval and replacing values of across first value through to the duplicates is not efficient as the other operations. However the key set retrieval is still efficient.

Since:

17.01

Author:

Ruwan Linton

Nested Class Summary
- Nested classes/interfaces inherited from interface java.util.Map
  Map.Entry<K,V>

Constructor Summary

Constructors
Constructor and Description
`MultiValueMap()`
`MultiValueMap(Map<K,V> firstValues, Map<K,List<V>> duplicates)` This will create a new `MultiValueMap` instance with the values of the `firstValues` and `duplicates`.
`MultiValueMap(MultiValueMap<K,V> multiValueMap)` This will create a new `MultiValueMap` instance with all the values of the `multiValueMap`.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`add(K key, V value)` Adds a new value with the given value for the given key
`void`	`clear()`
`boolean`	`containsFirstValue(Object value)` Checks whether the given value is there in the first values.
`boolean`	`containsKey(Object key)`
`boolean`	`containsValue(Object value)` Checks whether the given value is in either the first values or in any duplicates as well
`boolean`	`containsValueInDuplicates(Object value)` Checks whether the value is in duplicates excluding the first values
`Set<Map.Entry<K,List<V>>>`	`entrySet()`
`List<V>`	`get(Object key)` This method is not efficient, if you just need the first value use `getFirst(K)` instead
`List<V>`	`getDuplicates(K key)` Retrieves the only duplicates if there are any as a list of values for the given key
`V`	`getFirst(K key)` Retrieves the first value of the multi value map for the given key
`Map<K,List<V>>`	`getOnlyDuplicates()` Gives the duplicates only excluding the first values map, for entries without duplicates will be excluded from this map
`Map<K,V>`	`getSingleValueMap()` Gives the complete single value map view of the map
`boolean`	`isEmpty()`
`Set<K>`	`keySet()`
`List<V>`	`put(K key, List<V> value)`
`void`	`putAll(Map<? extends K,? extends List<V>> m)`
`List<V>`	`remove(Object key)`
`int`	`size()`
`Collection<List<V>>`	`values()`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.util.Map
compute, computeIfAbsent, computeIfPresent, equals, forEach, getOrDefault, hashCode, merge, putIfAbsent, remove, replace, replace, replaceAll

- Constructor Detail
  - MultiValueMap
```
public MultiValueMap()
```
  - MultiValueMap
```
public MultiValueMap(MultiValueMap<K,V> multiValueMap)
```
    This will create a new MultiValueMap instance with all the values of the multiValueMap. The two MultiValueMaps will refer separate objects for any Java immutable objects while both will refer the same objects for others.
    
    Parameters:
    
    multiValueMap - original MultiValueMap to be copied into this new one
  - MultiValueMap
```
public MultiValueMap(Map<K,V> firstValues,
                     Map<K,List<V>> duplicates)
```
    This will create a new MultiValueMap instance with the values of the firstValues and duplicates. The newly created MultiValueMap will refer separate objects for any Java immutable objects and will refer the same objects for others.
    
    Parameters:
    
    firstValues - Map to be copied as first values
    
    duplicates - Map to be copied as duplicates
- Method Detail
  - size
```
public int size()
```
    Specified by:
    
    size in interface Map<K,List<V>>
  - isEmpty
```
public boolean isEmpty()
```
    Specified by:
    
    isEmpty in interface Map<K,List<V>>
  - containsKey
```
public boolean containsKey(Object key)
```
    Specified by:
    
    containsKey in interface Map<K,List<V>>
  - containsValue
```
public boolean containsValue(Object value)
```
    Checks whether the given value is in either the first values or in any duplicates as well
    
    Specified by:
    
    containsValue in interface Map<K,List<V>>
    
    Parameters:
    
    value - the value to be searched for existence
    
    Returns:
    
    true of the value is there either in first values or in any duplicates
  - containsFirstValue
```
public boolean containsFirstValue(Object value)
```
    Checks whether the given value is there in the first values. It doesn't check the duplicates for the existence of the value
    
    Parameters:
    
    value - the value to be searched for existence in first values
    
    Returns:
    
    true if the value is in the first values
  - containsValueInDuplicates
```
public boolean containsValueInDuplicates(Object value)
```
    Checks whether the value is in duplicates excluding the first values
    
    Parameters:
    
    value - the value to be searched for the existence
    
    Returns:
    
    true if the value is there in the duplicates
  - get
```
public List<V> get(Object key)
```
    This method is not efficient, if you just need the first value use getFirst(K) instead
    
    Specified by:
    
    get in interface Map<K,List<V>>
    
    Parameters:
    
    key - the key to be fetched
    
    Returns:
    
    the list of values including duplicates
  - getFirst
```
public V getFirst(K key)
```
    Retrieves the first value of the multi value map for the given key
    
    Parameters:
    
    key - the key to fetch the first value
    
    Returns:
    
    the first value in the multi value map for the given key
  - getDuplicates
```
public List<V> getDuplicates(K key)
```
    Retrieves the only duplicates if there are any as a list of values for the given key
    
    Parameters:
    
    key - the key to fetch the duplicates
    
    Returns:
    
    the list of duplicates for the given key excluding the first value, or null if there are no duplicates
  - add
```
public void add(K key,
                V value)
```
    Adds a new value with the given value for the given key
    
    Parameters:
    
    key - the key to add the new value
    
    value - the new value to be added
  - put
```
public List<V> put(K key,
                   List<V> value)
```
    Specified by:
    
    put in interface Map<K,List<V>>
  - remove
```
public List<V> remove(Object key)
```
    Specified by:
    
    remove in interface Map<K,List<V>>
  - putAll
```
public void putAll(Map<? extends K,? extends List<V>> m)
```
    Specified by:
    
    putAll in interface Map<K,List<V>>
  - clear
```
public void clear()
```
    Specified by:
    
    clear in interface Map<K,List<V>>
  - getSingleValueMap
```
public Map<K,V> getSingleValueMap()
```
    Gives the complete single value map view of the map
    
    Returns:
    
    the single value map excluding any duplicates
  - getOnlyDuplicates
```
public Map<K,List<V>> getOnlyDuplicates()
```
    Gives the duplicates only excluding the first values map, for entries without duplicates will be excluded from this map
    
    Returns:
    
    the duplicates of the values
  - keySet
```
public Set<K> keySet()
```
    Specified by:
    
    keySet in interface Map<K,List<V>>
  - values
```
public Collection<List<V>> values()
```
    Specified by:
    
    values in interface Map<K,List<V>>
  - entrySet
```
public Set<Map.Entry<K,List<V>>> entrySet()
```
    Specified by:
    
    entrySet in interface Map<K,List<V>>

Class MultiValueMap<K,V>

Nested Class Summary

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

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface java.util.Map

Constructor Detail

MultiValueMap

MultiValueMap

MultiValueMap

Method Detail

size

isEmpty

containsKey

containsValue

containsFirstValue

containsValueInDuplicates

get

getFirst

getDuplicates

add

put

remove

putAll

clear

getSingleValueMap

getOnlyDuplicates

keySet

values

entrySet