001    /*
002     * Copyright 2010-2013 JetBrains s.r.o.
003     *
004     * Licensed under the Apache License, Version 2.0 (the "License");
005     * you may not use this file except in compliance with the License.
006     * You may obtain a copy of the License at
007     *
008     * http://www.apache.org/licenses/LICENSE-2.0
009     *
010     * Unless required by applicable law or agreed to in writing, software
011     * distributed under the License is distributed on an "AS IS" BASIS,
012     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013     * See the License for the specific language governing permissions and
014     * limitations under the License.
015     */
016    
017    package org.jetbrains.jet.lang.resolve.scopes;
018    
019    import com.google.common.collect.Lists;
020    import com.google.common.collect.Sets;
021    import org.jetbrains.annotations.NotNull;
022    import org.jetbrains.annotations.TestOnly;
023    import org.jetbrains.jet.lang.descriptors.*;
024    import org.jetbrains.jet.lang.resolve.name.LabelName;
025    import org.jetbrains.jet.lang.resolve.name.Name;
026    import org.jetbrains.jet.utils.Printer;
027    
028    import java.util.Collection;
029    import java.util.Collections;
030    import java.util.List;
031    import java.util.Set;
032    
033    public class ChainedScope implements JetScope {
034        private final DeclarationDescriptor containingDeclaration;
035        private final String debugName;
036        private final JetScope[] scopeChain;
037        private Collection<DeclarationDescriptor> allDescriptors;
038        private List<ReceiverParameterDescriptor> implicitReceiverHierarchy;
039    
040        public ChainedScope(DeclarationDescriptor containingDeclaration, JetScope... scopes) {
041            this(containingDeclaration, "Untitled chained scope", scopes);
042        }
043    
044        public ChainedScope(DeclarationDescriptor containingDeclaration, String debugName, JetScope... scopes) {
045            this.containingDeclaration = containingDeclaration;
046            scopeChain = scopes.clone();
047    
048            this.debugName = debugName;
049        }
050    
051        @Override
052        public ClassifierDescriptor getClassifier(@NotNull Name name) {
053            for (JetScope scope : scopeChain) {
054                ClassifierDescriptor classifier = scope.getClassifier(name);
055                if (classifier != null) return classifier;
056            }
057            return null;
058        }
059    
060        @Override
061        public NamespaceDescriptor getNamespace(@NotNull Name name) {
062            for (JetScope jetScope : scopeChain) {
063                NamespaceDescriptor namespace = jetScope.getNamespace(name);
064                if (namespace != null) {
065                    return namespace;
066                }
067            }
068            return null;
069        }
070    
071        @NotNull
072        @Override
073        public Set<VariableDescriptor> getProperties(@NotNull Name name) {
074            Set<VariableDescriptor> properties = Sets.newLinkedHashSet();
075            for (JetScope jetScope : scopeChain) {
076                properties.addAll(jetScope.getProperties(name));
077            }
078            return properties;
079        }
080    
081        @Override
082        public VariableDescriptor getLocalVariable(@NotNull Name name) {
083            for (JetScope jetScope : scopeChain) {
084                VariableDescriptor variable = jetScope.getLocalVariable(name);
085                if (variable != null) {
086                    return variable;
087                }
088            }
089            return null;
090        }
091    
092        @NotNull
093        @Override
094        public Set<FunctionDescriptor> getFunctions(@NotNull Name name) {
095            if (scopeChain.length == 0) {
096                return Collections.emptySet();
097            }
098    
099            Set<FunctionDescriptor> result = Sets.newLinkedHashSet();
100            for (JetScope jetScope : scopeChain) {
101                result.addAll(jetScope.getFunctions(name));
102            }
103            return result;
104        }
105    
106        @NotNull
107        @Override
108        public List<ReceiverParameterDescriptor> getImplicitReceiversHierarchy() {
109            if (implicitReceiverHierarchy == null) {
110                implicitReceiverHierarchy = Lists.newArrayList();
111                for (JetScope jetScope : scopeChain) {
112                    implicitReceiverHierarchy.addAll(jetScope.getImplicitReceiversHierarchy());
113                }
114            }
115            return implicitReceiverHierarchy;
116        }
117    
118        @NotNull
119        @Override
120        public DeclarationDescriptor getContainingDeclaration() {
121            return containingDeclaration;
122        }
123    
124        @NotNull
125        @Override
126        public Collection<DeclarationDescriptor> getDeclarationsByLabel(@NotNull LabelName labelName) {
127            for (JetScope jetScope : scopeChain) {
128                Collection<DeclarationDescriptor> declarationsByLabel = jetScope.getDeclarationsByLabel(labelName);
129                if (!declarationsByLabel.isEmpty()) return declarationsByLabel; // TODO : merge?
130            }
131            return Collections.emptyList();
132        }
133    
134        @NotNull
135        @Override
136        public Collection<DeclarationDescriptor> getAllDescriptors() {
137            if (allDescriptors == null) {
138                allDescriptors = Sets.newHashSet();
139                for (JetScope scope : scopeChain) {
140                    allDescriptors.addAll(scope.getAllDescriptors());
141                }
142            }
143            return allDescriptors;
144        }
145    
146        @NotNull
147        @Override
148        public Collection<DeclarationDescriptor> getOwnDeclaredDescriptors() {
149            throw new UnsupportedOperationException();
150        }
151    
152        @Override
153        public String toString() {
154            return debugName;
155        }
156    
157        @TestOnly
158        @Override
159        public void printScopeStructure(@NotNull Printer p) {
160            p.println(getClass().getSimpleName(), ": ", debugName, " {");
161            p.pushIndent();
162    
163            for (JetScope scope : scopeChain) {
164                scope.printScopeStructure(p);
165            }
166    
167            p.popIndent();
168            p.println("}");
169        }
170    }