genéricos

Was looking at the signature of the class methods Optional and I didn't understand what this <T> means in front of the ... t; Optional<T> empty() It returns a Optional<T>, right!? But why use a <T> in front of the method return?

I have a question that I cannot see answered, If anyone can give me a plausible explanation I will be grateful. Assuming I h ... since one element is inherited from the other and soon also inherits the interface comparable figure? Thank you right now.

Arrays in Java are covariants, that is, it is perfectly cool to do something like: Number[] meuArray = new Integer[10]; A ... id you decide to implement Covariant arrays? Original question: SOen-Why are arrays covariant but generics are invariant?

I need to pass two parameters to a generic function that returns database data and select only a few specific columns to disp ... (parameter passing): dgPesquisar.DataSource = UsuarioRepositorio.GetAll(null, u => u.login, u.Senha, u.NOmeCompleto );

I already know the ties while,repeat and for, but when I was looking at the types of loops, in the section I found the SUCH of the" generic for Loop". The text was in English.

The following question fell in the ifsp contest: In Java and C++ programming languages, the parametric polymorphism is ... How to define parametric polymorphism in Java? Be generics ? In this case, could we translate the word and say it's generic?

I was reading this post and came across this term monomorphization I would like to know: What is its meaning? when does this process occur? What performance gain/loss is achieved by this process?

I have a structure of type TTabelaX, which is basically a table that I will store elements of any type, that is, I can create ... = 0; return aux; } void inserir(TTabelaX* aux, ???){//<--como passar um parâmetro sem saber seu tipo? ... }

When working recently on a project, I noticed that we have several classes with basic CRUD functions and that repeat themselv ... return clienteDAO.findAll(); } public Cliente buscarPorId(String id){ return clienteDAO.findById(id).orElse(null); } }

When I know it is preferable to use generics or any in TypeScript?

As part of an ORM microplatform I'm developing, I'm defining a generic class that exclusively implements tight coupling (1 re ... ty<Course> { [...] However the use of new() is not allowed. Which model would better serve this type of behavior?