title: How does session work in java?
body: <p>If I put a map in session. Then if I remove an object from map. Will this also change the map in session or do I have to put the map in session again?</p>
  
  <pre><code>            Map map = new HashMap();
  
          map.put("1", "1");
          map.put("2", "2");
          map.put("3", "3");
          map.put("4", "4");
  
          Session session = getSession();
  
          session.setAttribute("myMap", map);
  
          map.remove("1");
  </code></pre>