public class User {
   private String name;
   private static Map<String, User> users = new HashMap<>();


   public User(String name) {
       this.name = name;
       users.put(name, this);
   }

   public String getName() {
       return name;
   }

   public static User getUser(String name) {
       User user = users.get(name);
       if (user == null) user = new User(name);
       return user;
   }
}