1 /**
2 * This file Copyright (c) 2013-2018 Magnolia International
3 * Ltd. (http://www.magnolia-cms.com). All rights reserved.
4 *
5 *
6 * This file is dual-licensed under both the Magnolia
7 * Network Agreement and the GNU General Public License.
8 * You may elect to use one or the other of these licenses.
9 *
10 * This file is distributed in the hope that it will be
11 * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
12 * implied warranty of MERCHANTABILITY or FITNESS FOR A
13 * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
14 * Redistribution, except as permitted by whichever of the GPL
15 * or MNA you select, is prohibited.
16 *
17 * 1. For the GPL license (GPL), you can redistribute and/or
18 * modify this file under the terms of the GNU General
19 * Public License, Version 3, as published by the Free Software
20 * Foundation. You should have received a copy of the GNU
21 * General Public License, Version 3 along with this program;
22 * if not, write to the Free Software Foundation, Inc., 51
23 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
24 *
25 * 2. For the Magnolia Network Agreement (MNA), this file
26 * and the accompanying materials are made available under the
27 * terms of the MNA which accompanies this distribution, and
28 * is available at http://www.magnolia-cms.com/mna.html
29 *
30 * Any modifications to this file must keep this entire header
31 * intact.
32 *
33 */
34 package info.magnolia.ui.contentapp.browser.drop;
35
36 import java.util.Collection;
37
38 import com.vaadin.shared.ui.grid.DropLocation;
39
40 /**
41 * Defines acceptance criteria for move operations.
42 *
43 * <p>A move operation may originate from drag-and-drop or from a move dialog.
44 *
45 * <p>DropConstraint class is configured in the {@link info.magnolia.ui.contentapp.configuration.WorkbenchDefinition}.
46 *
47 * @param <T> item type.
48 */
49 public interface DropConstraint<T> {
50
51 default boolean isAllowedAt(Collection<T> sources, T target, DropLocation dropLocation) {
52 boolean res = true;
53 for (T source : sources) {
54 res &= isAllowedAt(source, target, dropLocation);
55 }
56 return res;
57 }
58
59 /**
60 * Checks whether source item is allowed to be moved relative (based on the move location) to target item.
61 */
62 boolean isAllowedAt(T source, T target, DropLocation dropLocation);
63 }