public class Etudiant {

    public String nom;
    public String prenom;

    // cstr
    public Etudiant(String nom){
        this.nom = nom;
    }
    public Etudiant(String prenom){
        this.prenom = prenom;
    }

    // main

    public static void main(String[] args){
        Etudiant toto = new Etudiant("toto");
        Etudiant popo = new Etudiant("popo");

    System.out.println(toto.nom);
    System.out.println(popo.prenom);
    }

}