1 files changed, 94 insertions, 0 deletions
diff --git a/javaparser-symbol-solver-core/src/main/java/com/github/javaparser/symbolsolver/declarations/common/MethodDeclarationCommonLogic.java b/javaparser-symbol-solver-core/src/main/java/com/github/javaparser/symbolsolver/declarations/common/MethodDeclarationCommonLogic.java
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index 000000000..5d0063576
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+++ b/javaparser-symbol-solver-core/src/main/java/com/github/javaparser/symbolsolver/declarations/common/MethodDeclarationCommonLogic.java
@@ -0,0 +1,94 @@
+/*
+ * Copyright 2016 Federico Tomassetti
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.github.javaparser.symbolsolver.declarations.common;
+
+import com.github.javaparser.resolution.MethodUsage;
+import com.github.javaparser.resolution.declarations.ResolvedMethodDeclaration;
+import com.github.javaparser.resolution.declarations.ResolvedTypeParameterDeclaration;
+import com.github.javaparser.resolution.types.ResolvedType;
+import com.github.javaparser.resolution.types.ResolvedTypeVariable;
+import com.github.javaparser.symbolsolver.core.resolution.Context;
+import com.github.javaparser.symbolsolver.logic.InferenceContext;
+import com.github.javaparser.symbolsolver.model.resolution.TypeSolver;
+import com.github.javaparser.symbolsolver.reflectionmodel.MyObjectProvider;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+
+/**
+ * @author Federico Tomassetti
+ */
+public class MethodDeclarationCommonLogic {
+
+    private ResolvedMethodDeclaration methodDeclaration;
+    private TypeSolver typeSolver;
+
+    public MethodDeclarationCommonLogic(ResolvedMethodDeclaration methodDeclaration, TypeSolver typeSolver) {
+        this.methodDeclaration = methodDeclaration;
+        this.typeSolver = typeSolver;
+    }
+
+    public MethodUsage resolveTypeVariables(Context context, List<ResolvedType> parameterTypes) {
+        ResolvedType returnType = replaceTypeParams(methodDeclaration.getReturnType(), typeSolver, context);
+        List<ResolvedType> params = new ArrayList<>();
+        for (int i = 0; i < methodDeclaration.getNumberOfParams(); i++) {
+            ResolvedType replaced = replaceTypeParams(methodDeclaration.getParam(i).getType(), typeSolver, context);
+            params.add(replaced);
+        }
+
+        // We now look at the type parameter for the method which we can derive from the parameter types
+        // and then we replace them in the return type
+        // Map<TypeParameterDeclaration, Type> determinedTypeParameters = new HashMap<>();
+        InferenceContext inferenceContext = new InferenceContext(MyObjectProvider.INSTANCE);
+        for (int i = 0; i < methodDeclaration.getNumberOfParams() - (methodDeclaration.hasVariadicParameter() ? 1 : 0); i++) {
+            ResolvedType formalParamType = methodDeclaration.getParam(i).getType();
+            ResolvedType actualParamType = parameterTypes.get(i);
+            inferenceContext.addPair(formalParamType, actualParamType);
+        }
+
+        returnType = inferenceContext.resolve(inferenceContext.addSingle(returnType));
+
+        return new MethodUsage(methodDeclaration, params, returnType);
+    }
+
+    private ResolvedType replaceTypeParams(ResolvedType type, TypeSolver typeSolver, Context context) {
+        if (type.isTypeVariable()) {
+            ResolvedTypeParameterDeclaration typeParameter = type.asTypeParameter();
+            if (typeParameter.declaredOnType()) {
+                Optional<ResolvedType> typeParam = typeParamByName(typeParameter.getName(), typeSolver, context);
+                if (typeParam.isPresent()) {
+                    type = typeParam.get();
+                }
+            }
+        }
+
+        if (type.isReferenceType()) {
+            type.asReferenceType().transformTypeParameters(tp -> replaceTypeParams(tp, typeSolver, context));
+        }
+
+        return type;
+    }
+
+    protected Optional<ResolvedType> typeParamByName(String name, TypeSolver typeSolver, Context context) {
+        return methodDeclaration.getTypeParameters().stream().filter(tp -> tp.getName().equals(name)).map(tp -> toType(tp)).findFirst();
+    }
+
+    protected ResolvedType toType(ResolvedTypeParameterDeclaration typeParameterDeclaration) {
+        return new ResolvedTypeVariable(typeParameterDeclaration);
+    }
+}