Category "optional"

Handling the Optional which doesn't expected to be empty

I have the following method private Invoice createInvoice(SomeParameter someParameter) { Invoice invoice = new Invoice(); Optional<Customer> custo

failed to produce diagnostic for expression, Xcode 11.4, Moya

After updating to Xcode 11.4, I started to get this error Failed to produce diagnostic for expression please file a bug report On: let provider = MoyaProvider

What is the type of a Java empty Optional?

So the thing is I was checking Optional Java class and I noticed this in the public static<T> Optional<T> empty() doc: @param <T> The type of

Java 8 optional: ifPresent return object orElseThrow exception

I'm trying to make something like this: private String getStringIfObjectIsPresent(Optional<Object> object){ object.ifPresent(() ->{

Is there an option type?

This language being multi-paradigm, I wonder if there exists an Option type in R (Some/None), natively or in a package. It would be similar to F#, or to C# null

Type Mismatch cannot convert from type Optional<User> to User

I am trying to create a website that allows the user to update, edit, delete, etc., and I have got to the part of Updating or Editing user’s information.

Mockito.when().thenReturn() doesn't work or returns null

During the test there is a NullPointerException thrown. I tried to debug it and the only thing I worked out was that eventOptional is always null. Just as if Mo