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/*
 * Copyright (c) 2010, 2023, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package javafx.collections;

import java.text.Collator;
import java.util.Collection;
import java.util.Comparator;
import java.util.List;
import java.util.function.Predicate;

import javafx.beans.Observable;
import javafx.collections.transformation.FilteredList;
import javafx.collections.transformation.SortedList;

/**
 * A list that allows listeners to track changes when they occur. Implementations can be created using methods in {@link FXCollections}
 * such as {@link FXCollections#observableArrayList() observableArrayList}, or with a
 * {@link javafx.beans.property.SimpleListProperty SimpleListProperty}.
 *
 * @see ListChangeListener
 * @see ListChangeListener.Change
 * @param  the list element type
 * @since JavaFX 2.0
 */
public interface ObservableList extends List, Observable {
    /**
     * Add a listener to this observable list.
     * @param listener the listener for listening to the list changes
     */
    public void addListener(ListChangeListener listener);

    /**
     * Tries to remove a listener from this observable list. If the listener is not
     * attached to this list, nothing happens.
     * @param listener a listener to remove
     */
    public void removeListener(ListChangeListener listener);

    /**
     * A convenience method for var-arg addition of elements.
     * @param elements the elements to add
     * @return true (as specified by Collection.add(E))
     */
    public boolean addAll(E... elements);

    /**
     * Clears the ObservableList and adds all the elements passed as var-args.
     * @param elements the elements to set
     * @return true (as specified by Collection.add(E))
     * @throws NullPointerException if the specified arguments contain one or more null elements
     */
    public boolean setAll(E... elements);

    /**
     * Clears the ObservableList and adds all elements from the collection.
     * @param col the collection with elements that will be added to this observableArrayList
     * @return true (as specified by Collection.add(E))
     * @throws NullPointerException if the specified collection contains one or more null elements
     */
    public boolean setAll(Collection col);

    /**
     * A convenience method for var-arg usage of the {@link #removeAll(Collection) removeAll} method.
     * @param elements the elements to be removed
     * @return true if list changed as a result of this call
     */
    public boolean removeAll(E... elements);

    /**
     * A convenience method for var-arg usage of the {@link #retainAll(Collection) retainAll} method.
     * @param elements the elements to be retained
     * @return true if list changed as a result of this call
     */
    public boolean retainAll(E... elements);

    /**
     * A simplified way of calling {@code sublist(from, to).clear()}. As this is a common operation,
     * ObservableList has this method for convenient usage.
     * @param from the start of the range to remove (inclusive)
     * @param to the end of the range to remove (exclusive)
     * @throws IndexOutOfBoundsException if an illegal range is provided
     */
    public void remove(int from, int to);

    /**
     * Creates a {@link FilteredList} wrapper of this list using
     * the specified predicate.
     * @param predicate the predicate to use
     * @return new {@code FilteredList}
     * @since JavaFX 8.0
     */
    public default FilteredList filtered(Predicate predicate) {
        return new FilteredList<>(this, predicate);
    }

    /**
     * Creates a {@link SortedList} wrapper of this list using
     * the specified comparator.
     * @param comparator the comparator to use or null for unordered List
     * @return new {@code SortedList}
     * @since JavaFX 8.0
     */
    public default SortedList sorted(Comparator comparator) {
        return new SortedList<>(this, comparator);
    }

    /**
     * Creates a {@link SortedList} wrapper of this list with the natural
     * ordering.
     * @return new {@code SortedList}
     * @since JavaFX 8.0
     */
    public default SortedList sorted() {
        Comparator naturalOrder = new Comparator<>() {

            @Override
            public int compare(E o1, E o2) {
                if (o1 == null && o2 == null) {
                    return 0;
                }
                if (o1 == null) {
                    return -1;
                }
                if (o2 == null) {
                    return 1;
                }

                if (o1 instanceof Comparable) {
                    @SuppressWarnings("unchecked")
                    Comparable casted = (Comparable) o1;  // cast is not safe, assumes the comparable interface implemented is Comparable but it might be anything

                    return casted.compareTo(o2);
                }

                return Collator.getInstance().compare(o1.toString(), o2.toString());
            }
        };
        return sorted(naturalOrder);
    }
}