Convertir le getSelectedItem() en class

public class MyClass{
    String  Nom;
    String  Prenom;
    String  NumId;

    public MyClass(String Nom, String Prenom, String NumId)
    {
        this.Nom=Nom;
        this.Prenom=Prenom;
        this.NumId=NumId;
    }
public String getNom() {
        return Nom;
    }
    public void setNom(String Nom) {
        this.Nom = Nom;
    }
    public String getPrenom() {
        return Prenom;
    }
    public void setPrenom(String Prenom) {
        this.Prenom = Prenom;
    }
    public String getNumId() {
        return NumId;
    }
    public void setNumId(String NumId) {
        this.NumId= NumId;
    }
    public String toString() {
        return Nom +" "+ Prenom;
    }

}

main() {
Hashtable MyHashtable = new Hashtable();

MyClass NewClass = new MyClass("Albert","Laurent","1234");
MyHashtable .put(NewClass .getCode(),NewPlat);
 MyComboBox.addItem(NewClass );

NewClass = new MyClass("Jordan","Lejeune","4567");
hash .put(NewClass .getCode(),NewPlat);
MyComboBox.addItem(NewClass );

NewClass = new MyClass("Steve","Dupont","8901");
hash .put(NewClass .getCode(),NewPlat);
 MyComboBox.addItem(NewClass );
}

private void BtnMouseClicked(java.awt.event.MouseEvent evt) {   
    
MyClass Rechercher=MyComboBox.getSelectedItem();

 if (MyHashtable .containsKey(Rechercher.getNumId())
                 System.out.println("Super");
}