Spec-Zone .ru
спецификации, руководства, описания, API
001/*
002 * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
003 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
004 *
005 * This code is free software; you can redistribute it and/or modify it
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007 * published by the Free Software Foundation.  Oracle designates this
008 * particular file as subject to the "Classpath" exception as provided
009 * by Oracle in the LICENSE file that accompanied this code.
010 *
011 * This code is distributed in the hope that it will be useful, but WITHOUT
012 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
013 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
014 * version 2 for more details (a copy is included in the LICENSE file that
015 * accompanied this code).
016 *
017 * You should have received a copy of the GNU General Public License version
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019 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
020 *
021 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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024 */
025
026package javafx.collections;
027
028/**
029 * Interface that receives notifications of changes to an ObservableSet.
030 * @param <E> the element type
031 */
032public interface SetChangeListener<E> {
033
034    /**
035     * An elementary change done to an ObservableSet.
036     * Change contains information about an add or remove operation.
037     * Note that adding element that is already in the set does not
038     * modify the set and hence no change will be generated.
039     *
040     * @param <E> element type
041     */
042    public static abstract class Change<E> {
043
044        private ObservableSet<E> set;
045
046        /**
047         * Constructs a change associated with a set.
048         * @param set the source of the change
049         */
050        public Change(ObservableSet<E> set) {
051            this.set = set;
052        }
053
054        /**
055         * An observable set that is associated with the change.
056         * @return the source set
057         */
058        public ObservableSet<E> getSet() {
059            return set;
060        }
061
062        /**
063         * If this change is a result of add operation.
064         * @return true if a new element was added to the set
065         */
066        public abstract boolean wasAdded();
067
068        /**
069         * If this change is a result of removal operation.
070         * @return true if an old element was removed from the set
071         */
072        public abstract boolean wasRemoved();
073
074        /**
075         * Get the new element. Return null if this is a removal.
076         * @return the element that was just added
077         */
078        public abstract E getElementAdded();
079
080        /**
081         * Get the old element. Return null if this is an addition.
082         * @return the element that was just removed
083         */
084        public abstract E getElementRemoved();
085
086    }
087
088    /**
089     * Called after a change has been made to an ObservableSet.
090     * This method is called on every elementary change (add/remove) once.
091     * This means, complex changes like removeAll(Collection) or clear()
092     * may result in more than one call of onChanged method.
093     *
094     * @param change the change that was made
095     */
096    void onChanged(Change<? extends E> change);
097}