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
017package org.jetbrains.jet.lang.descriptors.impl;
018
019import org.jetbrains.annotations.NotNull;
020import org.jetbrains.jet.lang.descriptors.ClassDescriptor;
021import org.jetbrains.jet.lang.descriptors.DeclarationDescriptorVisitor;
022import org.jetbrains.jet.lang.descriptors.TypeParameterDescriptor;
023import org.jetbrains.jet.lang.resolve.scopes.JetScope;
024import org.jetbrains.jet.lang.resolve.scopes.SubstitutingScope;
025import org.jetbrains.jet.lang.types.*;
026
027import java.util.List;
028import java.util.Map;
029
030public abstract class ClassDescriptorBase implements ClassDescriptor {
031
032    protected JetType defaultType;
033
034    protected abstract JetScope getScopeForMemberLookup();
035
036    @NotNull
037    @Override
038    public JetScope getMemberScope(List<TypeProjection> typeArguments) {
039        assert typeArguments.size() == getTypeConstructor().getParameters().size() : "Illegal number of type arguments: expected " 
040                                                                                     + getTypeConstructor().getParameters().size() + " but was " + typeArguments.size() 
041                                                                                     + " for " + getTypeConstructor() + " " + getTypeConstructor().getParameters();
042        if (typeArguments.isEmpty()) return getScopeForMemberLookup();
043
044        List<TypeParameterDescriptor> typeParameters = getTypeConstructor().getParameters();
045        Map<TypeConstructor, TypeProjection> substitutionContext = SubstitutionUtils.buildSubstitutionContext(typeParameters, typeArguments);
046
047        // Unsafe substitutor is OK, because no recursion can hurt us upon a trivial substitution:
048        // all the types are written explicitly in the code already, they can not get infinite.
049        // One exception is *-projections, but they need to be handled separately anyways.
050        TypeSubstitutor substitutor = TypeSubstitutor.createUnsafe(substitutionContext);
051        return new SubstitutingScope(getScopeForMemberLookup(), substitutor);
052    }
053
054    @NotNull
055    @Override
056    public ClassDescriptor substitute(@NotNull TypeSubstitutor substitutor) {
057        if (substitutor.isEmpty()) {
058            return this;
059        }
060        return new LazySubstitutingClassDescriptor(this, substitutor);
061    }
062
063    @NotNull
064    @Override
065    public JetType getDefaultType() {
066        if (defaultType == null) {
067            defaultType = TypeUtils.makeUnsubstitutedType(this, getScopeForMemberLookup());
068        }
069        return defaultType;
070    }
071
072    @Override
073    public void acceptVoid(DeclarationDescriptorVisitor<Void, Void> visitor) {
074        visitor.visitClassDescriptor(this, null);
075    }
076
077    @Override
078    public <R, D> R accept(DeclarationDescriptorVisitor<R, D> visitor, D data) {
079        return visitor.visitClassDescriptor(this, data);
080    }
081}