2 * Copyright (c) 2019 PANTHEON.tech, s.r.o. and others. All rights reserved.
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6 * and is available at http://www.eclipse.org/legal/epl-v10.html
8 package org.opendaylight.yangtools.yang.model.export;
10 import static com.google.common.base.Preconditions.checkArgument;
11 import static com.google.common.base.Verify.verify;
12 import static java.util.Objects.requireNonNull;
14 import com.google.common.collect.ArrayListMultimap;
15 import com.google.common.collect.HashMultimap;
16 import com.google.common.collect.ImmutableMap;
17 import com.google.common.collect.ImmutableMap.Builder;
18 import com.google.common.collect.Maps;
19 import com.google.common.collect.Multimap;
20 import java.util.AbstractMap.SimpleImmutableEntry;
21 import java.util.Collection;
22 import java.util.HashMap;
23 import java.util.Iterator;
25 import java.util.Map.Entry;
26 import java.util.Optional;
27 import org.eclipse.jdt.annotation.Nullable;
28 import org.opendaylight.yangtools.yang.common.QNameModule;
29 import org.opendaylight.yangtools.yang.common.Revision;
30 import org.opendaylight.yangtools.yang.common.YangConstants;
31 import org.opendaylight.yangtools.yang.model.api.meta.DeclaredStatement;
32 import org.opendaylight.yangtools.yang.model.api.meta.EffectiveStatement;
33 import org.opendaylight.yangtools.yang.model.api.stmt.ModuleEffectiveStatement;
34 import org.opendaylight.yangtools.yang.model.api.stmt.ModuleEffectiveStatement.NameToEffectiveSubmoduleNamespace;
35 import org.opendaylight.yangtools.yang.model.api.stmt.ModuleEffectiveStatement.QNameModuleToPrefixNamespace;
36 import org.opendaylight.yangtools.yang.model.api.stmt.SubmoduleEffectiveStatement;
39 * Utility resolver to disambiguate imports.
41 final class StatementPrefixResolver {
42 private static final class Conflict {
43 private final Collection<Entry<DeclaredStatement<?>, String>> statements;
45 Conflict(final Collection<Entry<DeclaredStatement<?>, String>> entries) {
46 statements = requireNonNull(entries);
49 @Nullable String findPrefix(final DeclaredStatement<?> stmt) {
50 return statements.stream().filter(entry -> contains(entry.getKey(), stmt)).findFirst().map(Entry::getValue)
54 private static boolean contains(final DeclaredStatement<?> haystack, final DeclaredStatement<?> needle) {
55 if (haystack == needle) {
58 for (DeclaredStatement<?> child : haystack.declaredSubstatements()) {
59 if (contains(child, needle)) {
67 private final Map<QNameModule, ?> lookup;
69 private StatementPrefixResolver(final Map<QNameModule, String> map) {
70 lookup = ImmutableMap.copyOf(map);
73 private StatementPrefixResolver(final ImmutableMap<QNameModule, ?> map) {
74 lookup = requireNonNull(map);
77 static StatementPrefixResolver forModule(final ModuleEffectiveStatement module) {
78 final Map<QNameModule, String> imports = module.getAll(QNameModuleToPrefixNamespace.class);
79 final Collection<SubmoduleEffectiveStatement> submodules = module.getAll(
80 NameToEffectiveSubmoduleNamespace.class).values();
81 if (submodules.isEmpty()) {
82 // Simple: it's just the module
83 return new StatementPrefixResolver(imports);
86 // Stage one: check what everyone thinks about imports
87 final Map<String, Multimap<QNameModule, EffectiveStatement<?, ?>>> prefixToNamespaces = new HashMap<>();
88 indexPrefixes(prefixToNamespaces, imports, module);
89 for (SubmoduleEffectiveStatement submodule : submodules) {
90 indexPrefixes(prefixToNamespaces, submodule.getAll(QNameModuleToPrefixNamespace.class), submodule);
93 // Stage two: see what QNameModule -> prefix mappings there are. We will need to understand this in step three
94 final Multimap<QNameModule, String> namespaceToPrefixes = HashMultimap.create();
95 for (Entry<String, Multimap<QNameModule, EffectiveStatement<?,?>>> entry : prefixToNamespaces.entrySet()) {
96 for (QNameModule namespace : entry.getValue().keySet()) {
97 namespaceToPrefixes.put(namespace, entry.getKey());
101 // Stage three: resolve first order of conflicts, potentially completely resolving mappings...
102 final Builder<QNameModule, Object> builder = ImmutableMap.builderWithExpectedSize(prefixToNamespaces.size());
104 // ... first resolve unambiguous mappings ...
105 final Iterator<Entry<String, Multimap<QNameModule, EffectiveStatement<?, ?>>>> it =
106 prefixToNamespaces.entrySet().iterator();
107 while (it.hasNext()) {
108 final Entry<String, Multimap<QNameModule, EffectiveStatement<?, ?>>> entry = it.next();
109 final Multimap<QNameModule, EffectiveStatement<?, ?>> modules = entry.getValue();
110 if (modules.size() == 1) {
111 // Careful now: the namespace needs to be unambiguous
112 final QNameModule namespace = modules.keys().iterator().next();
113 if (namespaceToPrefixes.get(namespace).size() == 1) {
114 builder.put(namespace, entry.getKey());
120 // .. check for any remaining conflicts ...
121 if (!prefixToNamespaces.isEmpty()) {
122 final Multimap<QNameModule, Entry<DeclaredStatement<?>, String>> conflicts = ArrayListMultimap.create();
123 for (Entry<String, Multimap<QNameModule, EffectiveStatement<?, ?>>> entry : prefixToNamespaces.entrySet()) {
124 for (Entry<QNameModule, EffectiveStatement<?, ?>> namespace : entry.getValue().entries()) {
125 conflicts.put(namespace.getKey(), new SimpleImmutableEntry<>(namespace.getValue().getDeclared(),
130 builder.putAll(Maps.transformValues(conflicts.asMap(), Conflict::new));
133 return new StatementPrefixResolver(builder.build());
136 static StatementPrefixResolver forSubmodule(final SubmoduleEffectiveStatement submodule) {
137 return new StatementPrefixResolver(submodule.getAll(QNameModuleToPrefixNamespace.class));
140 Optional<String> findPrefix(final DeclaredStatement<?> stmt) {
141 final QNameModule module = stmt.statementDefinition().getStatementName().getModule();
142 if (YangConstants.RFC6020_YIN_MODULE.equals(module)) {
143 return Optional.empty();
146 final Object obj = lookup.get(module);
148 return decodeEntry(obj, stmt);
150 if (module.getRevision().isPresent()) {
151 throw new IllegalArgumentException("Failed to find prefix for statement " + stmt);
154 // FIXME: this is an artifact of commonly-bound statements in parser, which means a statement's name
155 // does not have a Revision. We'll need to find a solution to this which is acceptable. There
156 // are multiple ways of fixing this:
157 // - perhaps EffectiveModuleStatement should be giving us a statement-to-EffectiveModule map?
158 // - or DeclaredStatement should provide the prefix?
159 // The second one seems cleaner, as that means we would not have perform any lookup at all...
160 Entry<QNameModule, ?> match = null;
161 for (Entry<QNameModule, ?> entry : lookup.entrySet()) {
162 final QNameModule ns = entry.getKey();
163 if (module.equals(ns.withoutRevision()) && (match == null
164 || Revision.compare(match.getKey().getRevision(), ns.getRevision()) < 0)) {
169 return match == null ? null : decodeEntry(match.getValue(), stmt);
172 private static Optional<String> decodeEntry(final Object entry, final DeclaredStatement<?> stmt) {
173 if (entry instanceof String) {
174 return Optional.of((String)entry);
176 verify(entry instanceof Conflict, "Unexpected entry %s", entry);
177 final String prefix = ((Conflict) entry).findPrefix(stmt);
178 checkArgument(prefix != null, "Failed to find prefix for statement %s", stmt);
179 verify(!prefix.isEmpty(), "Empty prefix for statement %s", stmt);
180 return Optional.of(prefix);
183 private static void indexPrefixes(final Map<String, Multimap<QNameModule, EffectiveStatement<?, ?>>> map,
184 final Map<QNameModule, String> imports, final EffectiveStatement<?, ?> stmt) {
185 for (Entry<QNameModule, String> entry : imports.entrySet()) {
186 map.computeIfAbsent(entry.getValue(), key -> ArrayListMultimap.create()).put(entry.getKey(), stmt);