Package org.apache.commons.collections4.map

Class AbstractOrderedMapDecorator<K,V>

java.lang.Object
org.apache.commons.collections4.map.AbstractIterableMap<K,V>
org.apache.commons.collections4.map.AbstractMapDecorator<K,V>
org.apache.commons.collections4.map.AbstractOrderedMapDecorator<K,V>
Type Parameters:
K - the type of the keys in this map
V - the type of the values in this map
All Implemented Interfaces:
Map<K,V>, Get<K,V>, IterableGet<K,V>, IterableMap<K,V>, OrderedMap<K,V>, Put<K,V>
Direct Known Subclasses:
UnmodifiableOrderedMap
public abstract class AbstractOrderedMapDecorator<K,V> extends AbstractMapDecorator<K,V> implements OrderedMap<K,V>
Provides a base decorator that enables additional functionality to be added to an OrderedMap via decoration.

Methods are forwarded directly to the decorated map.

This implementation does not perform any special processing with the map views. Instead it simply returns the set/collection from the wrapped map. This may be undesirable, for example if you are trying to write a validating implementation it would provide a loophole around the validation. But, you might want that loophole, so this class is kept simple.

Since:
3.0

  • Constructor Details

  • Method Details

    • decorated

      protected OrderedMap<K,V> decorated()
      Gets the map being decorated.
      Overrides:
      decorated in class AbstractMapDecorator<K,V>
      Returns:
      the decorated map

    • firstKey

      public K firstKey()
      Description copied from interface: OrderedMap
      Gets the first key currently in this map.
      Specified by:
      firstKey in interface OrderedMap<K,V>
      Returns:
      the first key currently in this map

    • lastKey

      public K lastKey()
      Description copied from interface: OrderedMap
      Gets the last key currently in this map.
      Specified by:
      lastKey in interface OrderedMap<K,V>
      Returns:
      the last key currently in this map

    • mapIterator

      public OrderedMapIterator<K,V> mapIterator()
      Description copied from class: AbstractIterableMap
      Obtains a MapIterator over the map.

      A map iterator is an efficient way of iterating over maps. There is no need to access the entry set or use Map Entry objects. 

       IterableMap<String,Integer> map = new HashedMap<String,Integer>();
 MapIterator<String,Integer> it = map.mapIterator();
 while (it.hasNext()) {
   String key = it.next();
   Integer value = it.getValue();
   it.setValue(value + 1);
 }
      Specified by:
      mapIterator in interface IterableGet<K,V>
      Specified by:
      mapIterator in interface OrderedMap<K,V>
      Overrides:
      mapIterator in class AbstractIterableMap<K,V>
      Returns:
      a map iterator

    • nextKey

      public K nextKey(K key)
      Description copied from interface: OrderedMap
      Gets the next key after the one specified.
      Specified by:
      nextKey in interface OrderedMap<K,V>
      Parameters:
      key - the key to search for next from
      Returns:
      the next key, null if no match or at end

    • previousKey

      public K previousKey(K key)
      Description copied from interface: OrderedMap
      Gets the previous key before the one specified.
      Specified by:
      previousKey in interface OrderedMap<K,V>
      Parameters:
      key - the key to search for previous from
      Returns:
      the previous key, null if no match or at start