private static PsiType getFunctionalInterfaceTypeByContainingLambda(
@NotNull PsiLambdaExpression parentLambda) {
final PsiType parentInterfaceType = parentLambda.getFunctionalInterfaceType();
return parentInterfaceType != null
? getFunctionalInterfaceReturnType(parentInterfaceType)
: null;
}
@Nullable
public static PsiType getFunctionalInterfaceReturnType(PsiLambdaExpression expr) {
return getFunctionalInterfaceReturnType(expr.getFunctionalInterfaceType());
}