1 /*
2 * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.tools.jdeps;
27
28 import static com.sun.tools.jdeps.JdepsFilter.DEFAULT_FILTER;
29 import static com.sun.tools.jdeps.Module.trace;
30 import static com.sun.tools.jdeps.Graph.*;
31
32 import java.lang.module.ModuleDescriptor.Requires;
33 import java.io.IOException;
34 import java.util.Collections;
35 import java.util.Deque;
36 import java.util.HashMap;
37 import java.util.HashSet;
38 import java.util.LinkedList;
39 import java.util.Map;
40 import java.util.Optional;
41 import java.util.Set;
42 import java.util.stream.Collectors;
43 import java.util.stream.Stream;
44
45 /**
46 * Inverse transitive dependency analysis (compile-time view)
47 */
48 public class InverseDepsAnalyzer extends DepsAnalyzer {
49 // the end points for the resulting paths to be reported
50 private final Map<Archive, Set<Archive>> endPoints = new HashMap<>();
51 // target archives for inverse transitive dependence analysis
52 private final Set<Archive> targets = new HashSet<>();
53
54 public InverseDepsAnalyzer(JdepsConfiguration config,
55 JdepsFilter filter,
56 JdepsWriter writer,
57 Analyzer.Type verbose,
58 boolean apiOnly) {
59 super(config, filter, writer, verbose, apiOnly);
60 }
61
62 public boolean run() throws IOException {
63 try {
64 if (apiOnly) {
65 finder.parseExportedAPIs(rootArchives.stream());
66 } else {
67 finder.parse(rootArchives.stream());
68 }
69 archives.addAll(rootArchives);
70
71 Set<Archive> archives = archives();
72
73 // If -package or -regex is specified, the archives that reference
74 // the matching types are used as the targets for inverse
75 // transitive analysis. If -requires is specified, the
76 // specified modules are the targets.
77
78 if (filter.requiresFilter().isEmpty()) {
79 targets.addAll(archives);
80 } else {
81 filter.requiresFilter().stream()
82 .map(configuration::findModule)
83 .flatMap(Optional::stream)
84 .forEach(targets::add);
85 }
86
87 // If -package or -regex is specified, the end points are
88 // the matching archives. If -requires is specified,
89 // the end points are the modules specified in -requires.
90 if (filter.requiresFilter().isEmpty()) {
91 Map<Archive, Set<Archive>> dependences = finder.dependences();
92 targets.forEach(source -> endPoints.put(source, dependences.get(source)));
93 } else {
94 targets.forEach(t -> endPoints.put(t, Collections.emptySet()));
95 }
96
97 analyzer.run(archives, finder.locationToArchive());
98
99 // print the first-level of dependencies
100 if (writer != null) {
101 writer.generateOutput(archives, analyzer);
102 }
103
104 } finally {
105 finder.shutdown();
106 }
107 return true;
108 }
109
110 /**
111 * Returns the target archives determined from the dependency analysis.
112 *
113 * Inverse transitive dependency will find all nodes that depend
114 * upon the returned set of archives directly and indirectly.
115 */
116 public Set<Archive> targets() {
117 return Collections.unmodifiableSet(targets);
118 }
119
120 /**
121 * Finds all inverse transitive dependencies using the given requires set
122 * as the targets, if non-empty. If the given requires set is empty,
123 * use the archives depending the packages specified in -regex or -p options.
124 */
125 public Set<Deque<Archive>> inverseDependences() throws IOException {
126 // create a new dependency finder to do the analysis
127 DependencyFinder dependencyFinder = new DependencyFinder(configuration, DEFAULT_FILTER);
128 try {
129 // parse all archives in unnamed module to get compile-time dependences
130 Stream<Archive> archives =
131 Stream.concat(configuration.initialArchives().stream(),
132 configuration.classPathArchives().stream());
133 if (apiOnly) {
134 dependencyFinder.parseExportedAPIs(archives);
135 } else {
136 dependencyFinder.parse(archives);
137 }
138
139 Graph.Builder<Archive> builder = new Graph.Builder<>();
140 // include all target nodes
141 targets().forEach(builder::addNode);
142
143 // transpose the module graph
144 configuration.getModules().values().stream()
145 .forEach(m -> {
146 builder.addNode(m);
147 m.descriptor().requires().stream()
148 .map(Requires::name)
149 .map(configuration::findModule) // must be present
150 .forEach(v -> builder.addEdge(v.get(), m));
151 });
152
153 // add the dependences from the analysis
154 Map<Archive, Set<Archive>> dependences = dependencyFinder.dependences();
155 dependences.entrySet().stream()
156 .forEach(e -> {
157 Archive u = e.getKey();
158 builder.addNode(u);
159 e.getValue().forEach(v -> builder.addEdge(v, u));
160 });
161
162 // transposed dependence graph.
163 Graph<Archive> graph = builder.build();
164 trace("targets: %s%n", targets());
165
166 // Traverse from the targets and find all paths
167 // rebuild a graph with all nodes that depends on targets
168 // targets directly and indirectly
169 return targets().stream()
170 .map(t -> findPaths(graph, t))
171 .flatMap(Set::stream)
172 .collect(Collectors.toSet());
173 } finally {
174 dependencyFinder.shutdown();
175 }
176 }
177
178 /**
179 * Returns all paths reachable from the given targets.
180 */
181 private Set<Deque<Archive>> findPaths(Graph<Archive> graph, Archive target) {
182
183 // path is in reversed order
184 Deque<Archive> path = new LinkedList<>();
185 path.push(target);
186
187 Set<Edge<Archive>> visited = new HashSet<>();
188
189 Deque<Edge<Archive>> deque = new LinkedList<>();
190 deque.addAll(graph.edgesFrom(target));
191 if (deque.isEmpty()) {
192 return makePaths(path).collect(Collectors.toSet());
193 }
194
195 Set<Deque<Archive>> allPaths = new HashSet<>();
196 while (!deque.isEmpty()) {
197 Edge<Archive> edge = deque.pop();
198
199 if (visited.contains(edge))
200 continue;
201
202 Archive node = edge.v;
203 path.addLast(node);
204 visited.add(edge);
205
206 Set<Edge<Archive>> unvisitedDeps = graph.edgesFrom(node)
207 .stream()
208 .filter(e -> !visited.contains(e))
209 .collect(Collectors.toSet());
210
211 trace("visiting %s %s (%s)%n", edge, path, unvisitedDeps);
212 if (unvisitedDeps.isEmpty()) {
213 makePaths(path).forEach(allPaths::add);
214 path.removeLast();
215 }
216
217 // push unvisited adjacent edges
218 unvisitedDeps.stream().forEach(deque::push);
219
220
221 // when the adjacent edges of a node are visited, pop it from the path
222 while (!path.isEmpty()) {
223 if (visited.containsAll(graph.edgesFrom(path.peekLast())))
224 path.removeLast();
225 else
226 break;
227 }
228 }
229
230 return allPaths;
231 }
232
233 /**
234 * Prepend end point to the path
235 */
236 private Stream<Deque<Archive>> makePaths(Deque<Archive> path) {
237 Set<Archive> nodes = endPoints.get(path.peekFirst());
238 if (nodes == null || nodes.isEmpty()) {
239 return Stream.of(new LinkedList<>(path));
240 } else {
241 return nodes.stream().map(n -> {
242 Deque<Archive> newPath = new LinkedList<>();
243 newPath.addFirst(n);
244 newPath.addAll(path);
245 return newPath;
246 });
247 }
248 }
249 }