public class

LazySortedMap

extends LazyMap
implements SortedMap<K, V>
java.lang.Object
   ↳ org.apache.commons.collections.map.AbstractMapDecorator
     ↳ org.apache.commons.collections.map.LazyMap
       ↳ org.apache.commons.collections.map.LazySortedMap

Class Overview

Decorates another SortedMap to create objects in the map on demand.

When the 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 factory = new Factory() {
     public Object create() {
         return new Date();
     }
 }
 SortedMap lazy = Lazy.sortedMap(new HashMap(), factory);
 Object obj = lazy.get("NOW");
 
After the above code is executed, obj will contain 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 synchronizedSortedMap(SortedMap). This class may throw exceptions when accessed by concurrent threads without synchronization.

This class is Serializable from Commons Collections 3.1.

Summary

[Expand]
Inherited Fields
From class org.apache.commons.collections.map.LazyMap
From class org.apache.commons.collections.map.AbstractMapDecorator
Protected Constructors
LazySortedMap(SortedMap map, Factory factory)
Constructor that wraps (not copies).
LazySortedMap(SortedMap map, Transformer factory)
Constructor that wraps (not copies).
Public Methods
Comparator comparator()
static SortedMap decorate(SortedMap map, Transformer factory)
Factory method to create a lazily instantiated sorted map.
static SortedMap decorate(SortedMap map, Factory factory)
Factory method to create a lazily instantiated sorted map.
Object firstKey()
SortedMap headMap(Object toKey)
Object lastKey()
SortedMap subMap(Object fromKey, Object toKey)
SortedMap tailMap(Object fromKey)
Protected Methods
SortedMap getSortedMap()
Gets the map being decorated.
[Expand]
Inherited Methods
From class org.apache.commons.collections.map.LazyMap
From class org.apache.commons.collections.map.AbstractMapDecorator
From class java.lang.Object
From interface java.util.Map
From interface java.util.SortedMap

Protected Constructors

protected LazySortedMap (SortedMap map, Factory factory)

Constructor that wraps (not copies).

Parameters
map the map to decorate, must not be null
factory the factory to use, must not be null
Throws
IllegalArgumentException if map or factory is null

protected LazySortedMap (SortedMap map, Transformer factory)

Constructor that wraps (not copies).

Parameters
map the map to decorate, must not be null
factory the factory to use, must not be null
Throws
IllegalArgumentException if map or factory is null

Public Methods

public Comparator comparator ()

public static SortedMap decorate (SortedMap map, Transformer factory)

Factory method to create a lazily instantiated sorted map.

Parameters
map the map to decorate, must not be null
factory the factory to use, must not be null
Throws
IllegalArgumentException if map or factory is null

public static SortedMap decorate (SortedMap map, Factory factory)

Factory method to create a lazily instantiated sorted map.

Parameters
map the map to decorate, must not be null
factory the factory to use, must not be null
Throws
IllegalArgumentException if map or factory is null

public Object firstKey ()

public SortedMap headMap (Object toKey)

public Object lastKey ()

public SortedMap subMap (Object fromKey, Object toKey)

public SortedMap tailMap (Object fromKey)

Protected Methods

protected SortedMap getSortedMap ()

Gets the map being decorated.

Returns
  • the decorated map