1 /**
2 * This file Copyright (c) 2015-2016 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.resourceloader;
35
36 /**
37 * Common interface for all resource file origins (e.g. file-system, classpath, JCR).
38 *
39 * @param <P> the type of {@link Resource} this implementation of ResourceOrigin produces.
40 */
41 public interface ResourceOrigin<P extends Resource> {
42
43 /**
44 * Returns the name of this origin. This may be used to describe/differentiate origin instances, and generate i18n keys accordingly.
45 */
46 String getName();
47
48 /**
49 * Returns the {@link Resource} for this origin's declared root.
50 */
51 P getRoot();
52
53 /**
54 * Traverses this ResourceOrigin from the root, according to the given {@link ResourceVisitor}.
55 *
56 * @see ResourceVisitor
57 * @see info.magnolia.resourceloader.util.PredicatedResourceVisitor
58 * @see info.magnolia.resourceloader.util.ResourceTreeWalker
59 */
60 void traverseWith(ResourceVisitor visitor);
61
62 /**
63 * Sets up observation for this origin, and hooks it to the given callback {@link ResourceVisitor}.
64 *
65 * @see ResourceVisitor
66 * @see info.magnolia.resourceloader.util.PredicatedResourceVisitor
67 */
68 void watchForChanges(ResourceVisitor visitor);
69
70 /**
71 * Retrieves a {@link Resource} object based on the given path. The given path may or may not start with a
72 * leading /, but will always be considered relative to whatever root path this origin uses; for the user of this
73 * class, such paths should thus be considered absolute, depending on the implementation, they may be relative
74 * to some other path. Directory traversal navigation should be prohibited by implementations for security reasons.
75 *
76 * @throws ResourceNotFoundException if the path does not exist in this ResourceOrigin
77 */
78 P getByPath(String path);
79 // P getByPath(Resource relativeTo, String relPath);
80
81 boolean hasPath(String path);
82
83 /**
84 * Thrown when a given path can't be found.
85 */
86 class ResourceNotFoundException extends RuntimeException {
87 public ResourceNotFoundException(ResourceOrigin origin, String path) {
88 super("No resource found for path " + path + " in origin " + origin.getName());
89 }
90 }
91
92 }