public class LinkedMap extends AbstractLinkedMap implements Serializable, Cloneable
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.
AbstractLinkedMap.EntrySetIterator, AbstractLinkedMap.KeySetIterator, AbstractLinkedMap.LinkEntry, AbstractLinkedMap.LinkIterator, AbstractLinkedMap.LinkMapIterator, AbstractLinkedMap.ValuesIteratorAbstractHashedMap.EntrySet, AbstractHashedMap.HashEntry, AbstractHashedMap.HashIterator, AbstractHashedMap.HashMapIterator, AbstractHashedMap.KeySet, AbstractHashedMap.ValuesAbstractMap.SimpleEntry, AbstractMap.SimpleImmutableEntryheaderdata, DEFAULT_CAPACITY, DEFAULT_LOAD_FACTOR, DEFAULT_THRESHOLD, entrySet, GETKEY_INVALID, GETVALUE_INVALID, keySet, loadFactor, MAXIMUM_CAPACITY, modCount, NO_NEXT_ENTRY, NO_PREVIOUS_ENTRY, NULL, REMOVE_INVALID, SETVALUE_INVALID, size, threshold, values| Constructor and Description |
|---|
LinkedMap()
Constructs a new empty map with default size and load factor.
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LinkedMap(int initialCapacity)
Constructs a new, empty map with the specified initial capacity.
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LinkedMap(int initialCapacity,
float loadFactor)
Constructs a new, empty map with the specified initial capacity and
load factor.
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LinkedMap(Map map)
Constructor copying elements from another map.
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| Modifier and Type | Method and Description |
|---|---|
List |
asList()
Gets an unmodifiable List view of the keys.
|
Object |
clone()
Clones the map without cloning the keys or values.
|
Object |
get(int index)
Gets the key at the specified index.
|
Object |
getValue(int index)
Gets the value at the specified index.
|
int |
indexOf(Object key)
Gets the index of the specified key.
|
Object |
remove(int index)
Removes the element at the specified index.
|
addEntry, clear, containsValue, createEntry, createEntrySetIterator, createKeySetIterator, createValuesIterator, entryAfter, entryBefore, firstKey, getEntry, init, lastKey, mapIterator, nextKey, orderedMapIterator, previousKey, removeEntryaddMapping, calculateNewCapacity, calculateThreshold, checkCapacity, containsKey, convertKey, destroyEntry, doReadObject, doWriteObject, ensureCapacity, entryHashCode, entryKey, entryNext, entrySet, entryValue, equals, get, getEntry, hash, hashCode, hashIndex, isEmpty, isEqualKey, isEqualValue, keySet, put, putAll, remove, removeMapping, reuseEntry, size, toString, updateEntry, valuespublic LinkedMap()
public LinkedMap(int initialCapacity)
initialCapacity - the initial capacityIllegalArgumentException - if the initial capacity is less than onepublic LinkedMap(int initialCapacity,
float loadFactor)
initialCapacity - the initial capacityloadFactor - the load factorIllegalArgumentException - if the initial capacity is less than oneIllegalArgumentException - if the load factor is less than zeropublic LinkedMap(Map map)
map - the map to copyNullPointerException - if the map is nullpublic Object clone()
clone in class AbstractHashedMappublic Object get(int index)
index - the index to retrieveIndexOutOfBoundsException - if the index is invalidpublic Object getValue(int index)
index - the index to retrieveIndexOutOfBoundsException - if the index is invalidpublic int indexOf(Object key)
key - the key to find the index ofpublic Object remove(int index)
index - the index of the object to removekey,
or null if none existedIndexOutOfBoundsException - if the index is invalidpublic List asList()
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().
AbstractHashedMap.keySet()Copyright © 2001–2015 The Apache Software Foundation. All rights reserved.