1 /**
2 * This file Copyright (c) 2003-2010 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.module.model.reader;
35
36 import info.magnolia.module.model.DependencyDefinition;
37 import info.magnolia.module.model.ModuleDefinition;
38
39 import java.util.ArrayList;
40 import java.util.Collections;
41 import java.util.Comparator;
42 import java.util.List;
43 import java.util.Map;
44
45 /**
46 * A comparator used to sort modules according to their dependencies.
47 * It hardcodes "core" to be first and "webapp" to be last.
48 *
49 * @author gjoseph
50 * @version $Revision: $ ($Author: $)
51 */
52 class DependencyLevelComparator implements Comparator<ModuleDefinition> {
53 private final Map<String, ModuleDefinition> allKnownModulesDefinitions;
54
55 DependencyLevelComparator(Map<String, ModuleDefinition> allKnownModulesDefinitions) {
56 this.allKnownModulesDefinitions = allKnownModulesDefinitions;
57 }
58
59 public int compare(ModuleDefinition def1, ModuleDefinition def2) {
60
61 // the core module must always be installed/updated/started first
62 if ("core".equals(def1.getName())) {
63 return -1;
64 } else if ("core".equals(def2.getName())) {
65 return 1;
66 }
67
68 // the webapp module must always be installed/updated/started last
69 if ("webapp".equals(def1.getName())) {
70 return 1;
71 } else if ("webapp".equals(def2.getName())) {
72 return -1;
73 }
74
75 int level1 = calcDependencyDepth(def1);
76 int level2 = calcDependencyDepth(def2);
77
78 // lower level first
79 int dif = level1 - level2;
80 if (dif != 0) {
81 return dif;
82 }
83
84 // rest is ordered alphabetically
85 return def1.getName().compareTo(def2.getName());
86
87 }
88
89 /**
90 * Calculates the depth of dependency. 0 means no dependency. If none of the dependencies
91 * has itself dependencies, the level will be 1. If one or more of the dependencies has
92 * dependencies that has a dependency it would return 2. And so on...
93 *
94 * @param def module definition
95 * @return the level
96 */
97 protected int calcDependencyDepth(ModuleDefinition def) {
98 if (def.getDependencies() == null || def.getDependencies().size() == 0) {
99 return 0;
100 }
101 final List<Integer> dependencyLevels = new ArrayList<Integer>();
102 for (final DependencyDefinition dep : def.getDependencies()) {
103 final ModuleDefinition depDef = allKnownModulesDefinitions.get(dep.getName());
104 if (depDef == null && !dep.isOptional()) {
105 throw new RuntimeException("Missing definition for module:" + dep.getName());
106 } else if (depDef != null) {
107 dependencyLevels.add(new Integer(calcDependencyLevel(depDef)));
108 }
109 }
110 return (Collections.max(dependencyLevels)).intValue() + 1;
111 }
112
113 /**
114 * @deprecated since Magnolia 4.1, renamed to calcDependencyDepth()
115 */
116 protected int calcDependencyLevel(ModuleDefinition def) {
117 return calcDependencyDepth(def);
118 }
119
120 }