Retain Objects Value After Refreshing JSP Page : My program has to go through a learning step that takes around 15 mins to complete. The result of this learning is two Models stored into two public objects which will be then used in other classes. I put this learning step in the  method `public void init()` so as to be performed at the start of the server. The problem is, every time I refresh the page or send different GET parameter, the server re-do the learning step.. I have to wait another 15 minutes just to see the effect of a small change. I was wondering if there is a way to retain the value of some objects throughout the running of the program and the server.



    public static Model model1;
    public static Model model2;
    
    @Override
    public void init()
    {
    model1= readModel(source1)
    model2= readModel(source2)
    }

PS. I am using Servlets with JSP pages and Tomcat Server.