org.apache.commons.collections.map

Class TransformedMap

java.lang.Object

org.apache.commons.collections.map.AbstractMapDecorator

org.apache.commons.collections.map.TransformedMap

All Implemented Interfaces:

java.io.Serializable, java.util.Map

Direct Known Subclasses:

TransformedSortedMap

public class TransformedMap
extends AbstractMapDecorator
implements java.io.Serializable

Decorates another Map to transform objects that are added.

The Map put methods and Map.Entry setValue method are affected by this class. Thus objects must be removed or searched for using their transformed form. For example, if the transformation converts Strings to Integers, you must use the Integer form to remove objects.

Note that TransformedMap 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.

This class is Serializable from Commons Collections 3.1.

Since:

Commons Collections 3.0

See Also:

Serialized Form

Nested Class Summary

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

java.util.Map.Entry<K,V>

Method Summary

Modifier and Type	Method and Description
static java.util.Map	decorate(java.util.Map map, Transformer keyTransformer, Transformer valueTransformer) Factory method to create a transforming map.
static java.util.Map	decorateTransform(java.util.Map map, Transformer keyTransformer, Transformer valueTransformer) Factory method to create a transforming map that will transform existing contents of the specified map.
java.util.Set	entrySet()
java.lang.Object	put(java.lang.Object key, java.lang.Object value)
void	putAll(java.util.Map mapToCopy)

Methods inherited from class org.apache.commons.collections.map.AbstractMapDecorator

clear, containsKey, containsValue, equals, get, hashCode, isEmpty, keySet, 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, forEach, getOrDefault, merge, putIfAbsent, remove, replace, replace, replaceAll

Method Detail

decorate

public static java.util.Map decorate(java.util.Map map,
                                     Transformer keyTransformer,
                                     Transformer valueTransformer)

Factory method to create a transforming map.

If there are any elements already in the map being decorated, they are NOT transformed. Constrast this with decorateTransform(java.util.Map, org.apache.commons.collections.Transformer, org.apache.commons.collections.Transformer).

Parameters:

map - the map to decorate, must not be null

keyTransformer - the transformer to use for key conversion, null means no transformation

valueTransformer - the transformer to use for value conversion, null means no transformation

Throws:

java.lang.IllegalArgumentException - if map is null

decorateTransform

public static java.util.Map decorateTransform(java.util.Map map,
                                              Transformer keyTransformer,
                                              Transformer valueTransformer)

Factory method to create a transforming map that will transform existing contents of the specified map.

If there are any elements already in the map being decorated, they will be transformed by this method. Constrast this with decorate(java.util.Map, org.apache.commons.collections.Transformer, org.apache.commons.collections.Transformer).

Parameters:

map - the map to decorate, must not be null

keyTransformer - the transformer to use for key conversion, null means no transformation

valueTransformer - the transformer to use for value conversion, null means no transformation

Throws:

java.lang.IllegalArgumentException - if map is null

Since:

Commons Collections 3.2

put

public java.lang.Object put(java.lang.Object key,
                            java.lang.Object value)

Specified by:

put in interface java.util.Map

Overrides:

put in class AbstractMapDecorator

putAll

public void putAll(java.util.Map mapToCopy)

Specified by:

putAll in interface java.util.Map

Overrides:

putAll in class AbstractMapDecorator

entrySet

public java.util.Set entrySet()

Specified by:

entrySet in interface java.util.Map

Overrides:

entrySet in class AbstractMapDecorator