private void migrateMethodReturnExpression(PsiType migrationType, PsiMethod method) {
    final PsiCodeBlock block = method.getBody();
    if (block != null) {
      block.accept(new JavaRecursiveElementWalkingVisitor() {
        @Override
        public void visitReturnStatement(@NotNull PsiReturnStatement statement) {
          final PsiExpression value = statement.getReturnValue();
          if (value != null) {
            final PsiType type = getTypeEvaluator().evaluateType(value);
            if (type != null && !type.equals(migrationType)) {
              if (PsiTypes.voidType().equals(migrationType)) {
                convertExpression(value, migrationType, type, true);
              }
              else {
                migrateExpressionType(value, migrationType, statement, TypeConversionUtil.isAssignable(migrationType, type), true);
              }
            }
          }
        }

        @Override
        public void visitClass(@NotNull PsiClass aClass) {}

        @Override
        public void visitLambdaExpression(@NotNull PsiLambdaExpression expression) {}
      });
    }
  }
private void migrateMethodReturnExpression(PsiType migrationType, PsiMethod method)