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	/*
	* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. See the NOTICE file distributed with
	* 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
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/
	package org.apache.commons.collections4.list;

	import java.util.Collection;
	import java.util.List;
	import java.util.ListIterator;

	import org.apache.commons.collections4.Transformer;
	import org.apache.commons.collections4.collection.TransformedCollection;
	import org.apache.commons.collections4.iterators.AbstractListIteratorDecorator;

	/**
	* Decorates another <code>List</code> to transform objects that are added.
	* <p>
	* The add and set methods 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>
	* This class is Serializable from Commons Collections 3.1.
	* </p>
	*
	* @since 3.0
	*/
	public class TransformedList<E> extends TransformedCollection<E> implements List<E> {

	/** Serialization version */
	private static final long serialVersionUID = 1077193035000013141L;

	/**
	* Factory method to create a transforming list.
	* <p>
	* If there are any elements already in the list being decorated, they
	* are NOT transformed.
	* Contrast this with {@link #transformedList(List, Transformer)}.
	*
	* @param <E> the type of the elements in the list
	* @param list the list to decorate, must not be null
	* @param transformer the transformer to use for conversion, must not be null
	* @return a new transformed list
	* @throws NullPointerException if list or transformer is null
	* @since 4.0
	*/
	public static <E> TransformedList<E> transformingList(final List<E> list,
	final Transformer<? super E, ? extends E> transformer) {
	return new TransformedList<>(list, transformer);
	}

	/**
	* Factory method to create a transforming list that will transform
	* existing contents of the specified list.
	* <p>
	* If there are any elements already in the list being decorated, they
	* will be transformed by this method.
	* Contrast this with {@link #transformingList(List, Transformer)}.
	*
	* @param <E> the type of the elements in the list
	* @param list the list to decorate, must not be null
	* @param transformer the transformer to use for conversion, must not be null
	* @return a new transformed List
	* @throws NullPointerException if list or transformer is null
	* @since 4.0
	*/
	public static <E> TransformedList<E> transformedList(final List<E> list,
	final Transformer<? super E, ? extends E> transformer) {
	final TransformedList<E> decorated = new TransformedList<>(list, transformer);
	if (list.size() > 0) {
	@SuppressWarnings("unchecked") // list is of type E
	final E[] values = (E[]) list.toArray(); // NOPMD - false positive for generics
	list.clear();
	for (final E value : values) {
	decorated.decorated().add(transformer.transform(value));
	}
	}
	return decorated;
	}

	//-----------------------------------------------------------------------
	/**
	* Constructor that wraps (not copies).
	* <p>
	* If there are any elements already in the list being decorated, they
	* are NOT transformed.
	*
	* @param list the list to decorate, must not be null
	* @param transformer the transformer to use for conversion, must not be null
	* @throws NullPointerException if list or transformer is null
	*/
	protected TransformedList(final List<E> list, final Transformer<? super E, ? extends E> transformer) {
	super(list, transformer);
	}

	/**
	* Gets the decorated list.
	*
	* @return the decorated list
	*/
	protected List<E> getList() {
	return (List<E>) decorated();
	}

	@Override
	public boolean equals(final Object object) {
	return object == this \|\| decorated().equals(object);
	}

	@Override
	public int hashCode() {
	return decorated().hashCode();
	}

	//-----------------------------------------------------------------------

	@Override
	public E get(final int index) {
	return getList().get(index);
	}

	@Override
	public int indexOf(final Object object) {
	return getList().indexOf(object);
	}

	@Override
	public int lastIndexOf(final Object object) {
	return getList().lastIndexOf(object);
	}

	@Override
	public E remove(final int index) {
	return getList().remove(index);
	}

	//-----------------------------------------------------------------------

	@Override
	public void add(final int index, E object) {
	object = transform(object);
	getList().add(index, object);
	}

	@Override
	public boolean addAll(final int index, Collection<? extends E> coll) {
	coll = transform(coll);
	return getList().addAll(index, coll);
	}

	@Override
	public ListIterator<E> listIterator() {
	return listIterator(0);
	}

	@Override
	public ListIterator<E> listIterator(final int i) {
	return new TransformedListIterator(getList().listIterator(i));
	}

	@Override
	public E set(final int index, E object) {
	object = transform(object);
	return getList().set(index, object);
	}

	@Override
	public List<E> subList(final int fromIndex, final int toIndex) {
	final List<E> sub = getList().subList(fromIndex, toIndex);
	return new TransformedList<>(sub, transformer);
	}

	/**
	* Inner class Iterator for the TransformedList
	*/
	protected class TransformedListIterator extends AbstractListIteratorDecorator<E> {

	/**
	* Create a new transformed list iterator.
	*
	* @param iterator the list iterator to decorate
	*/
	protected TransformedListIterator(final ListIterator<E> iterator) {
	super(iterator);
	}

	@Override
	public void add(E object) {
	object = transform(object);
	getListIterator().add(object);
	}

	@Override
	public void set(E object) {
	object = transform(object);
	getListIterator().set(object);
	}
	}

	}

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