How to transform attributes into properties?

Question

In C#, I can avoid using getter and setter, transforming the attributes into properties, as below:

public class Pessoa {
    public int pes_idade { get; set; }
    public string pes_nome { get; set; }
}

You can do this in Java?

Answer 1

In C# you create property that is nothing more than a private field (and not, attribute which is something else in C#) with a couple of methods (can be one) that will give access to this field. You don’t see them as methods (it’s syntactic sugar) but it is what it is. It would be basically this:

public class Pessoa {
    private int idade;
    public int getIdade() { return idade; }
    public void setIdade(int value) { idade = value; }
    private String nome;
    public String getNome() { return nome; }
    public void setNome(String value) { nome = value; }
}

I put in the Github for future reference.

In Java it does not have this facility, so you have to do it in hand, just like this. Unless you use the Lombok (see comments). I don’t see a lot of people doing it, there must be a reason (it may be just ignorance, but it seems that’s not all). See What is the Lombok?

Functioning of that standard

This creates an indirect that is useful for dynamic versioning and loading of modules, because the logic of the access passes to the method, so whenever you update the method in the class, everyone who call it will receive the new execution, even if nothing that does access has been recompiled (only the component of the changed class has been recompiled).

If you used the direct field, that wouldn’t be possible because the access is done directly. A change in this class required the recompilation of the entire application to ensure that access was done according to the new functioning.

So in some cases using the field is not a problem, even if in the future you need to switch to a method that has a processing. But if you’re not sure that a change can affect the entire application, then it’s best to make sure by already putting a method that does a very basic operation, which is the property in C#, or the pattern of getter and Setter in Java.

I’m not a fan of the term attribute, I prefer field.

Answer 2

In Java it’s like this:

public class Pessoa {

    private String nome;
    private int idade;


    public String getNome() {
        return nome;
    }

    public int getIdade() {
        return idade;
    }

    public void setNome(String nome) {
        this.nome = nome;
    }

    public void setIdade(int idade) {
        this.idade = idade;
    }

}