LinkedMap ("The Adobe AEM Quickstart and Web Application.")

java.lang.Object
- java.util.AbstractMap<K,V>
- - org.apache.commons.collections4.map.AbstractHashedMap<K,V>
  - - org.apache.commons.collections4.map.AbstractLinkedMap<K,V>
    - - org.apache.commons.collections4.map.LinkedMap<K,V>

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, java.util.Map<K,V>, Get<K,V>, IterableGet<K,V>, IterableMap<K,V>, OrderedMap<K,V>, Put<K,V>
```
public class LinkedMap<K,V>
extends AbstractLinkedMap<K,V>
implements java.io.Serializable, java.lang.Cloneable
```
A Map implementation that maintains the order of the entries. In this implementation order is maintained by original insertion.
This implementation improves on the JDK1.4 LinkedHashMap by adding the MapIterator functionality, additional convenience methods and allowing bidirectional iteration. It also implements OrderedMap. In addition, non-interface methods are provided to access the map by index.
The orderedMapIterator() method provides direct access to a bidirectional iterator. The iterators from the other views can also be cast to OrderedIterator if required.
All the available iterators can be reset back to the start by casting to ResettableIterator and calling reset().
The implementation is also designed to be subclassed, with lots of useful methods exposed.
Note that LinkedMap is not synchronized and is not thread-safe. If you wish to use this map from multiple threads concurrently, you must use appropriate synchronization. The simplest approach is to wrap this map using Collections.synchronizedMap(Map). This class may throw exceptions when accessed by concurrent threads without synchronization.

Since:

3.0

See Also:

Serialized Form

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

Constructor Summary

Constructors
Constructor and Description
`LinkedMap()` Constructs a new empty map with default size and load factor.
`LinkedMap(int initialCapacity)` Constructs a new, empty map with the specified initial capacity.
`LinkedMap(int initialCapacity, float loadFactor)` Constructs a new, empty map with the specified initial capacity and load factor.
`LinkedMap(java.util.Map<? extends K,? extends V> map)` Constructor copying elements from another map.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`java.util.List<K>`	`asList()` Gets an unmodifiable List view of the keys.
`LinkedMap<K,V>`	`clone()` Clones the map without cloning the keys or values.
`K`	`get(int index)` Gets the key at the specified index.
`V`	`getValue(int index)` Gets the value at the specified index.
`int`	`indexOf(java.lang.Object key)` Gets the index of the specified key.
`V`	`remove(int index)` Removes the element at the specified index.

Methods inherited from class org.apache.commons.collections4.map.AbstractLinkedMap
clear, containsValue, firstKey, lastKey, mapIterator, nextKey, previousKey

Methods inherited from class org.apache.commons.collections4.map.AbstractHashedMap
containsKey, entrySet, equals, get, hashCode, isEmpty, keySet, put, putAll, remove, size, toString, values

Methods inherited from class java.lang.Object
getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Map
compute, computeIfAbsent, computeIfPresent, containsKey, entrySet, equals, forEach, get, getOrDefault, hashCode, isEmpty, keySet, merge, put, putAll, putIfAbsent, remove, remove, replace, replace, replaceAll, size, values

Methods inherited from interface org.apache.commons.collections4.Put
put, putAll

Methods inherited from interface org.apache.commons.collections4.Get
containsKey, entrySet, get, isEmpty, keySet, remove, size, values

- Constructor Detail
  - LinkedMap
```
public LinkedMap()
```
    Constructs a new empty map with default size and load factor.
  - LinkedMap
```
public LinkedMap(int initialCapacity)
```
    Constructs a new, empty map with the specified initial capacity.
    
    Parameters:
    
    initialCapacity - the initial capacity
    
    Throws:
    
    java.lang.IllegalArgumentException - if the initial capacity is negative
  - LinkedMap
```
public LinkedMap(int initialCapacity,
                 float loadFactor)
```
    Constructs a new, empty map with the specified initial capacity and load factor.
    
    Parameters:
    
    initialCapacity - the initial capacity
    
    loadFactor - the load factor
    
    Throws:
    
    java.lang.IllegalArgumentException - if the initial capacity is negative
    
    java.lang.IllegalArgumentException - if the load factor is less than zero
  - LinkedMap
```
public LinkedMap(java.util.Map<? extends K,? extends V> map)
```
    Constructor copying elements from another map.
    
    Parameters:
    
    map - the map to copy
    
    Throws:
    
    java.lang.NullPointerException - if the map is null
- Method Detail
  - clone
```
public LinkedMap<K,V> clone()
```
    Clones the map without cloning the keys or values.
    
    Returns:
    
    a shallow clone
  - get
```
public K get(int index)
```
    Gets the key at the specified index.
    
    Parameters:
    
    index - the index to retrieve
    
    Returns:
    
    the key at the specified index
    
    Throws:
    
    java.lang.IndexOutOfBoundsException - if the index is invalid
  - getValue
```
public V getValue(int index)
```
    Gets the value at the specified index.
    
    Parameters:
    
    index - the index to retrieve
    
    Returns:
    
    the value at the specified index
    
    Throws:
    
    java.lang.IndexOutOfBoundsException - if the index is invalid
  - indexOf
```
public int indexOf(java.lang.Object key)
```
    Gets the index of the specified key.
    
    Parameters:
    
    key - the key to find the index of
    
    Returns:
    
    the index, or -1 if not found
  - remove
```
public V remove(int index)
```
    Removes the element at the specified index.
    
    Parameters:
    
    index - the index of the object to remove
    
    Returns:
    
    the previous value corresponding the key, or null if none existed
    
    Throws:
    
    java.lang.IndexOutOfBoundsException - if the index is invalid
  - asList
```
public java.util.List<K> asList()
```
    Gets an unmodifiable List view of the keys.
    The returned list is unmodifiable because changes to the values of the list (using ListIterator.set(Object)) will effectively remove the value from the list and reinsert that value at the end of the list, which is an unexpected side effect of changing the value of a list. This occurs because changing the key, changes when the mapping is added to the map and thus where it appears in the list.
    An alternative to this method is to use AbstractHashedMap.keySet().
    
    Returns:
    
    The ordered list of keys.
    
    See Also:
    
    AbstractHashedMap.keySet()

Class LinkedMap<K,V>

Nested Class Summary

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

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

Constructor Summary

Method Summary

Methods inherited from class org.apache.commons.collections4.map.AbstractLinkedMap

Methods inherited from class org.apache.commons.collections4.map.AbstractHashedMap

Methods inherited from class java.lang.Object

Methods inherited from interface java.util.Map

Methods inherited from interface org.apache.commons.collections4.Put

Methods inherited from interface org.apache.commons.collections4.Get

Constructor Detail

LinkedMap

LinkedMap

LinkedMap

LinkedMap

Method Detail

clone

get

getValue

indexOf

remove

asList