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 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
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 *      http://www.apache.org/licenses/LICENSE-2.0
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 * Unless required by applicable law or agreed to in writing, software
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package org.apache.commons.collections4.map;

import java.util.Comparator;
import java.util.Map;
import java.util.SortedMap;

import org.apache.commons.collections4.Transformer;

Decorates another SortedMap 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 TransformedSortedMap 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. This class may throw exceptions when accessed by concurrent threads without synchronization.

This class is Serializable from Commons Collections 3.1.

Type parameters:
  • <K> – the type of the keys in this map
  • <V> – the type of the values in this map
Since:3.0
/** * Decorates another <code>SortedMap </code> to transform objects that are added. * <p> * 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. * </p> * <p> * <strong>Note that TransformedSortedMap is not synchronized and is not thread-safe.</strong> * 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 {@link java.util.Collections#synchronizedSortedMap}. This class may throw * exceptions when accessed by concurrent threads without synchronization. * </p> * <p> * This class is Serializable from Commons Collections 3.1. * </p> * * @param <K> the type of the keys in this map * @param <V> the type of the values in this map * @since 3.0 */
public class TransformedSortedMap<K, V> extends TransformedMap<K, V> implements SortedMap<K, V> {
Serialization version
/** Serialization version */
private static final long serialVersionUID = -8751771676410385778L;
Factory method to create a transforming sorted map.

If there are any elements already in the map being decorated, they are NOT transformed. Contrast this with transformedSortedMap(SortedMap<Object,Object>, Transformer<? super Object,? extends Object>, Transformer<? super Object,? extends Object>).

Params:
  • map – the map to decorate, must not be null
  • keyTransformer – the predicate to validate the keys, null means no transformation
  • valueTransformer – the predicate to validate to values, null means no transformation
Type parameters:
  • <K> – the key type
  • <V> – the value type
Throws:
Returns:a new transformed sorted map
Since:4.0
/** * Factory method to create a transforming sorted map. * <p> * If there are any elements already in the map being decorated, they are NOT transformed. * Contrast this with {@link #transformedSortedMap(SortedMap, Transformer, Transformer)}. * * @param <K> the key type * @param <V> the value type * @param map the map to decorate, must not be null * @param keyTransformer the predicate to validate the keys, null means no transformation * @param valueTransformer the predicate to validate to values, null means no transformation * @return a new transformed sorted map * @throws NullPointerException if the map is null * @since 4.0 */
public static <K, V> TransformedSortedMap<K, V> transformingSortedMap(final SortedMap<K, V> map, final Transformer<? super K, ? extends K> keyTransformer, final Transformer<? super V, ? extends V> valueTransformer) { return new TransformedSortedMap<>(map, keyTransformer, valueTransformer); }
Factory method to create a transforming sorted 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. Contrast this with transformingSortedMap(SortedMap<Object,Object>, Transformer<? super Object,? extends Object>, Transformer<? super Object,? extends Object>).

Params:
  • 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
Type parameters:
  • <K> – the key type
  • <V> – the value type
Throws:
Returns:a new transformed sorted map
Since:4.0
/** * Factory method to create a transforming sorted map that will transform * existing contents of the specified map. * <p> * If there are any elements already in the map being decorated, they * will be transformed by this method. * Contrast this with {@link #transformingSortedMap(SortedMap, Transformer, Transformer)}. * * @param <K> the key type * @param <V> the value type * @param map the map to decorate, must not be null * @param keyTransformer the transformer to use for key conversion, null means no transformation * @param valueTransformer the transformer to use for value conversion, null means no transformation * @return a new transformed sorted map * @throws NullPointerException if map is null * @since 4.0 */
public static <K, V> TransformedSortedMap<K, V> transformedSortedMap(final SortedMap<K, V> map, final Transformer<? super K, ? extends K> keyTransformer, final Transformer<? super V, ? extends V> valueTransformer) { final TransformedSortedMap<K, V> decorated = new TransformedSortedMap<>(map, keyTransformer, valueTransformer); if (map.size() > 0) { final Map<K, V> transformed = decorated.transformMap(map); decorated.clear(); decorated.decorated().putAll(transformed); // avoids double transformation } return decorated; } //-----------------------------------------------------------------------
Constructor that wraps (not copies).

If there are any elements already in the collection being decorated, they are NOT transformed.

Params:
  • map – the map to decorate, must not be null
  • keyTransformer – the predicate to validate the keys, null means no transformation
  • valueTransformer – the predicate to validate to values, null means no transformation
Throws:
/** * Constructor that wraps (not copies). * <p> * If there are any elements already in the collection being decorated, they * are NOT transformed.</p> * * @param map the map to decorate, must not be null * @param keyTransformer the predicate to validate the keys, null means no transformation * @param valueTransformer the predicate to validate to values, null means no transformation * @throws NullPointerException if the map is null */
protected TransformedSortedMap(final SortedMap<K, V> map, final Transformer<? super K, ? extends K> keyTransformer, final Transformer<? super V, ? extends V> valueTransformer) { super(map, keyTransformer, valueTransformer); } //-----------------------------------------------------------------------
Gets the map being decorated.
Returns:the decorated map
/** * Gets the map being decorated. * * @return the decorated map */
protected SortedMap<K, V> getSortedMap() { return (SortedMap<K, V>) map; } //----------------------------------------------------------------------- @Override public K firstKey() { return getSortedMap().firstKey(); } @Override public K lastKey() { return getSortedMap().lastKey(); } @Override public Comparator<? super K> comparator() { return getSortedMap().comparator(); } @Override public SortedMap<K, V> subMap(final K fromKey, final K toKey) { final SortedMap<K, V> map = getSortedMap().subMap(fromKey, toKey); return new TransformedSortedMap<>(map, keyTransformer, valueTransformer); } @Override public SortedMap<K, V> headMap(final K toKey) { final SortedMap<K, V> map = getSortedMap().headMap(toKey); return new TransformedSortedMap<>(map, keyTransformer, valueTransformer); } @Override public SortedMap<K, V> tailMap(final K fromKey) { final SortedMap<K, V> map = getSortedMap().tailMap(fromKey); return new TransformedSortedMap<>(map, keyTransformer, valueTransformer); } }