Examples with ResolvedVoidType com.github.javaparser.resolution.types.ResolvedVoidType used on opensource projects

Example 1 with ResolvedVoidType

use of com.github.javaparser.resolution.types.ResolvedVoidType in project javaparser by javaparser.

the class TypeExtractor method visit.

@Override
public ResolvedType visit(LambdaExpr node, Boolean solveLambdas) {
    if (requireParentNode(node) instanceof MethodCallExpr) {
        MethodCallExpr callExpr = (MethodCallExpr) requireParentNode(node);
        int pos = JavaParserSymbolDeclaration.getParamPos(node);
        SymbolReference<ResolvedMethodDeclaration> refMethod = facade.solve(callExpr);
        if (!refMethod.isSolved()) {
            throw new com.github.javaparser.resolution.UnsolvedSymbolException(requireParentNode(node).toString(), callExpr.getName().getId());
        }
        logger.finest("getType on lambda expr " + refMethod.getCorrespondingDeclaration().getName());
        if (solveLambdas) {
            // The type parameter referred here should be the java.util.stream.Stream.T
            ResolvedType result = refMethod.getCorrespondingDeclaration().getParam(pos).getType();
            if (callExpr.getScope().isPresent()) {
                Expression scope = callExpr.getScope().get();
                // If it is a static call we should not try to get the type of the scope
                boolean staticCall = false;
                if (scope instanceof NameExpr) {
                    NameExpr nameExpr = (NameExpr) scope;
                    try {
                        SymbolReference<ResolvedTypeDeclaration> type = JavaParserFactory.getContext(nameExpr, typeSolver).solveType(nameExpr.getName().getId(), typeSolver);
                        if (type.isSolved()) {
                            staticCall = true;
                        }
                    } catch (Exception e) {
                    }
                }
                if (!staticCall) {
                    ResolvedType scopeType = facade.getType(scope);
                    if (scopeType.isReferenceType()) {
                        result = scopeType.asReferenceType().useThisTypeParametersOnTheGivenType(result);
                    }
                }
            }
            // We need to replace the type variables
            Context ctx = JavaParserFactory.getContext(node, typeSolver);
            result = solveGenericTypes(result, ctx, typeSolver);
            // We should find out which is the functional method (e.g., apply) and replace the params of the
            // solveLambdas with it, to derive so the values. We should also consider the value returned by the
            // lambdas
            Optional<MethodUsage> functionalMethod = FunctionalInterfaceLogic.getFunctionalMethod(result);
            if (functionalMethod.isPresent()) {
                LambdaExpr lambdaExpr = node;
                InferenceContext lambdaCtx = new InferenceContext(MyObjectProvider.INSTANCE);
                InferenceContext funcInterfaceCtx = new InferenceContext(MyObjectProvider.INSTANCE);
                // At this point parameterType
                // if Function<T=? super Stream.T, ? extends map.R>
                // we should replace Stream.T
                ResolvedType functionalInterfaceType = ReferenceTypeImpl.undeterminedParameters(functionalMethod.get().getDeclaration().declaringType(), typeSolver);
                lambdaCtx.addPair(result, functionalInterfaceType);
                ResolvedType actualType;
                if (lambdaExpr.getBody() instanceof ExpressionStmt) {
                    actualType = facade.getType(((ExpressionStmt) lambdaExpr.getBody()).getExpression());
                } else if (lambdaExpr.getBody() instanceof BlockStmt) {
                    BlockStmt blockStmt = (BlockStmt) lambdaExpr.getBody();
                    // Get all the return statements in the lambda block
                    List<ReturnStmt> returnStmts = blockStmt.findAll(ReturnStmt.class);
                    if (returnStmts.size() > 0) {
                        actualType = returnStmts.stream().map(returnStmt -> returnStmt.getExpression().map(e -> facade.getType(e)).orElse(ResolvedVoidType.INSTANCE)).filter(x -> x != null && !x.isVoid() && !x.isNull()).findFirst().orElse(ResolvedVoidType.INSTANCE);
                    } else {
                        return ResolvedVoidType.INSTANCE;
                    }
                } else {
                    throw new UnsupportedOperationException();
                }
                ResolvedType formalType = functionalMethod.get().returnType();
                // Infer the functional interfaces' return vs actual type
                funcInterfaceCtx.addPair(formalType, actualType);
                // Substitute to obtain a new type
                ResolvedType functionalTypeWithReturn = funcInterfaceCtx.resolve(funcInterfaceCtx.addSingle(functionalInterfaceType));
                // we don't need to bother inferring types
                if (!(formalType instanceof ResolvedVoidType)) {
                    lambdaCtx.addPair(result, functionalTypeWithReturn);
                    result = lambdaCtx.resolve(lambdaCtx.addSingle(result));
                }
            }
            return result;
        } else {
            return refMethod.getCorrespondingDeclaration().getParam(pos).getType();
        }
    } else {
        throw new UnsupportedOperationException("The type of a lambda expr depends on the position and its return value");
    }
}