K
- the type of the keys in this mapV
- the type of the values in this mappublic class LazySortedMap<K,V> extends LazyMap<K,V> implements SortedMap<K,V>
SortedMap
to create objects in the map on demand.
When the LazyMap.get(Object)
method is called with a key that does not
exist in the map, the factory is used to create the object. The created
object will be added to the map using the requested key.
For instance:
Factory<Date> factory = new Factory<Date>() { public Date create() { return new Date(); } } SortedMap<String, Date> lazy = LazySortedMap.lazySortedMap(new HashMap<String, Date>(), factory); Date date = lazy.get("NOW");
After the above code is executed, date
will refer to
a new Date
instance. Furthermore, that Date
instance is mapped to the "NOW" key in the map.
Note that LazySortedMap 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.synchronizedSortedMap(java.util.SortedMap<K, V>)
. This class may throw
exceptions when accessed by concurrent threads without synchronization.
This class is Serializable from Commons Collections 3.1.
Modifier | Constructor and Description |
---|---|
protected |
LazySortedMap(SortedMap<K,V> map,
Factory<? extends V> factory)
Constructor that wraps (not copies).
|
protected |
LazySortedMap(SortedMap<K,V> map,
Transformer<? super K,? extends V> factory)
Constructor that wraps (not copies).
|
Modifier and Type | Method and Description |
---|---|
Comparator<? super K> |
comparator() |
K |
firstKey() |
protected SortedMap<K,V> |
getSortedMap()
Gets the map being decorated.
|
SortedMap<K,V> |
headMap(K toKey) |
K |
lastKey() |
static <K,V> LazySortedMap<K,V> |
lazySortedMap(SortedMap<K,V> map,
Factory<? extends V> factory)
Factory method to create a lazily instantiated sorted map.
|
static <K,V> LazySortedMap<K,V> |
lazySortedMap(SortedMap<K,V> map,
Transformer<? super K,? extends V> factory)
Factory method to create a lazily instantiated sorted map.
|
SortedMap<K,V> |
subMap(K fromKey,
K toKey) |
SortedMap<K,V> |
tailMap(K fromKey) |
clear, containsKey, containsValue, decorated, entrySet, equals, hashCode, isEmpty, keySet, put, putAll, remove, size, toString, values
mapIterator
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
clear, compute, computeIfAbsent, computeIfPresent, containsKey, containsValue, equals, forEach, get, getOrDefault, hashCode, isEmpty, merge, put, putAll, putIfAbsent, remove, remove, replace, replace, replaceAll, size
protected LazySortedMap(SortedMap<K,V> map, Factory<? extends V> factory)
map
- the map to decorate, must not be nullfactory
- the factory to use, must not be nullNullPointerException
- if map or factory is nullprotected LazySortedMap(SortedMap<K,V> map, Transformer<? super K,? extends V> factory)
map
- the map to decorate, must not be nullfactory
- the factory to use, must not be nullNullPointerException
- if map or factory is nullpublic static <K,V> LazySortedMap<K,V> lazySortedMap(SortedMap<K,V> map, Factory<? extends V> factory)
K
- the key typeV
- the value typemap
- the map to decorate, must not be nullfactory
- the factory to use, must not be nullNullPointerException
- if map or factory is nullpublic static <K,V> LazySortedMap<K,V> lazySortedMap(SortedMap<K,V> map, Transformer<? super K,? extends V> factory)
K
- the key typeV
- the value typemap
- the map to decorate, must not be nullfactory
- the factory to use, must not be nullNullPointerException
- if map or factory is nullprotected SortedMap<K,V> getSortedMap()
public Comparator<? super K> comparator()
comparator
in interface SortedMap<K,V>
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