001 /*
002 * Copyright 2010-2015 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.kotlin.resolve.calls.inference;
018
019 import com.google.common.collect.Lists;
020 import com.google.common.collect.Maps;
021 import org.jetbrains.annotations.NotNull;
022 import org.jetbrains.annotations.Nullable;
023 import org.jetbrains.kotlin.descriptors.TypeParameterDescriptor;
024 import org.jetbrains.kotlin.types.*;
025 import org.jetbrains.kotlin.types.checker.JetTypeChecker;
026
027 import java.lang.reflect.InvocationTargetException;
028 import java.lang.reflect.Method;
029 import java.util.*;
030
031 public class ConstraintsUtil {
032 @Nullable
033 public static TypeParameterDescriptor getFirstConflictingParameter(@NotNull ConstraintSystem constraintSystem) {
034 for (TypeParameterDescriptor typeParameter : constraintSystem.getTypeVariables()) {
035 TypeBounds constraints = constraintSystem.getTypeBounds(typeParameter);
036 if (constraints.getValues().size() > 1) {
037 return typeParameter;
038 }
039 }
040 return null;
041 }
042
043 @NotNull
044 public static Collection<TypeSubstitutor> getSubstitutorsForConflictingParameters(@NotNull ConstraintSystem constraintSystem) {
045 TypeParameterDescriptor firstConflictingParameter = getFirstConflictingParameter(constraintSystem);
046 if (firstConflictingParameter == null) return Collections.emptyList();
047
048 Collection<JetType> conflictingTypes = constraintSystem.getTypeBounds(firstConflictingParameter).getValues();
049
050 List<Map<TypeConstructor, TypeProjection>> substitutionContexts = Lists.newArrayList();
051 for (JetType type : conflictingTypes) {
052 Map<TypeConstructor, TypeProjection> context = Maps.newLinkedHashMap();
053 context.put(firstConflictingParameter.getTypeConstructor(), new TypeProjectionImpl(type));
054 substitutionContexts.add(context);
055 }
056
057 for (TypeParameterDescriptor typeParameter : constraintSystem.getTypeVariables()) {
058 if (typeParameter == firstConflictingParameter) continue;
059
060 JetType safeType = getSafeValue(constraintSystem, typeParameter);
061 for (Map<TypeConstructor, TypeProjection> context : substitutionContexts) {
062 TypeProjection typeProjection = new TypeProjectionImpl(safeType);
063 context.put(typeParameter.getTypeConstructor(), typeProjection);
064 }
065 }
066 Collection<TypeSubstitutor> typeSubstitutors = Lists.newArrayList();
067 for (Map<TypeConstructor, TypeProjection> context : substitutionContexts) {
068 typeSubstitutors.add(TypeSubstitutor.create(context));
069 }
070 return typeSubstitutors;
071 }
072
073 @NotNull
074 public static JetType getSafeValue(@NotNull ConstraintSystem constraintSystem, @NotNull TypeParameterDescriptor typeParameter) {
075 JetType type = constraintSystem.getTypeBounds(typeParameter).getValue();
076 if (type != null) {
077 return type;
078 }
079 //todo may be error type
080 return typeParameter.getUpperBoundsAsType();
081 }
082
083 public static boolean checkUpperBoundIsSatisfied(
084 @NotNull ConstraintSystem constraintSystem,
085 @NotNull TypeParameterDescriptor typeParameter,
086 boolean substituteOtherTypeParametersInBound
087 ) {
088 JetType type = constraintSystem.getTypeBounds(typeParameter).getValue();
089 if (type == null) return true;
090 for (JetType upperBound : typeParameter.getUpperBounds()) {
091 if (!substituteOtherTypeParametersInBound && TypeUtils.dependsOnTypeParameters(upperBound, constraintSystem.getTypeVariables())) {
092 continue;
093 }
094 JetType substitutedUpperBound = constraintSystem.getResultingSubstitutor().substitute(upperBound, Variance.INVARIANT);
095
096 assert substitutedUpperBound != null : "We wanted to substitute projections as a result for " + typeParameter;
097 if (!JetTypeChecker.DEFAULT.isSubtypeOf(type, substitutedUpperBound)) {
098 return false;
099 }
100 }
101 return true;
102 }
103
104 public static boolean checkBoundsAreSatisfied(
105 @NotNull ConstraintSystem constraintSystem,
106 boolean substituteOtherTypeParametersInBounds
107 ) {
108 for (TypeParameterDescriptor typeVariable : constraintSystem.getTypeVariables()) {
109 if (!checkUpperBoundIsSatisfied(constraintSystem, typeVariable, substituteOtherTypeParametersInBounds)) {
110 return false;
111 }
112 }
113 return true;
114 }
115
116 public static String getDebugMessageForStatus(@NotNull ConstraintSystemStatus status) {
117 StringBuilder sb = new StringBuilder();
118 List<Method> interestingMethods = Lists.newArrayList();
119 for (Method method : status.getClass().getMethods()) {
120 String name = method.getName();
121 boolean isInteresting = name.startsWith("is") || name.startsWith("has") && !name.equals("hashCode");
122 if (method.getParameterTypes().length == 0 && isInteresting) {
123 interestingMethods.add(method);
124 }
125 }
126 Collections.sort(interestingMethods, new Comparator<Method>() {
127 @Override
128 public int compare(@NotNull Method method1, @NotNull Method method2) {
129 return method1.getName().compareTo(method2.getName());
130 }
131 });
132 for (Iterator<Method> iterator = interestingMethods.iterator(); iterator.hasNext(); ) {
133 Method method = iterator.next();
134 try {
135 sb.append("-").append(method.getName()).append(": ").append(method.invoke(status));
136 if (iterator.hasNext()) {
137 sb.append("\n");
138 }
139 }
140 catch (IllegalAccessException e) {
141 sb.append(e.getMessage());
142 }
143 catch (InvocationTargetException e) {
144 sb.append(e.getMessage());
145 }
146 }
147 return sb.toString();
148 }
149 }