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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.Predicate;
	import org.apache.commons.collections4.collection.PredicatedCollection;
	import org.apache.commons.collections4.iterators.AbstractListIteratorDecorator;

	/**
	* Decorates another <code>List</code> to validate that all additions
	* match a specified predicate.
	* <p>
	* This list exists to provide validation for the decorated list.
	* It is normally created to decorate an empty list.
	* If an object cannot be added to the list, an IllegalArgumentException is thrown.
	* </p>
	* <p>
	* One usage would be to ensure that no null entries are added to the list.
	* </p>
	* <pre>
	* {@code
	* List<String> list =
	* PredicatedList.predicatedList(new ArrayList<String>(), PredicateUtils.notNullPredicate());
	* }
	* </pre>
	* <p>
	* This class is Serializable from Commons Collections 3.1.
	* </p>
	*
	* @since 3.0
	*/
	public class PredicatedList<E> extends PredicatedCollection<E> implements List<E> {

	/** Serialization version */
	private static final long serialVersionUID = -5722039223898659102L;

	/**
	* Factory method to create a predicated (validating) list.
	* <p>
	* If there are any elements already in the list being decorated, they
	* are validated.
	*
	* @param <T> the type of the elements in the list
	* @param list the list to decorate, must not be null
	* @param predicate the predicate to use for validation, must not be null
	* @return a new predicated list
	* @throws NullPointerException if list or predicate is null
	* @throws IllegalArgumentException if the list contains invalid elements
	* @since 4.0
	*/
	public static <T> PredicatedList<T> predicatedList(final List<T> list, final Predicate<? super T> predicate) {
	return new PredicatedList<>(list, predicate);
	}

	//-----------------------------------------------------------------------
	/**
	* Constructor that wraps (not copies).
	* <p>
	* If there are any elements already in the list being decorated, they
	* are validated.
	*
	* @param list the list to decorate, must not be null
	* @param predicate the predicate to use for validation, must not be null
	* @throws NullPointerException if list or predicate is null
	* @throws IllegalArgumentException if the list contains invalid elements
	*/
	protected PredicatedList(final List<E> list, final Predicate<? super E> predicate) {
	super(list, predicate);
	}

	/**
	* Gets the list being decorated.
	*
	* @return the decorated list
	*/
	@Override
	protected List<E> decorated() {
	return (List<E>) super.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 decorated().get(index);
	}

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

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

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

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

	@Override
	public void add(final int index, final E object) {
	validate(object);
	decorated().add(index, object);
	}

	@Override
	public boolean addAll(final int index, final Collection<? extends E> coll) {
	for (final E aColl : coll) {
	validate(aColl);
	}
	return decorated().addAll(index, coll);
	}

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

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

	@Override
	public E set(final int index, final E object) {
	validate(object);
	return decorated().set(index, object);
	}

	@Override
	public List<E> subList(final int fromIndex, final int toIndex) {
	final List<E> sub = decorated().subList(fromIndex, toIndex);
	return new PredicatedList<>(sub, predicate);
	}

	/**
	* Inner class Iterator for the PredicatedList
	*/
	protected class PredicatedListIterator extends AbstractListIteratorDecorator<E> {

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

	@Override
	public void add(final E object) {
	validate(object);
	getListIterator().add(object);
	}

	@Override
	public void set(final E object) {
	validate(object);
	getListIterator().set(object);
	}
	}

	}

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