get set and remove demo

SessionContextHolder2.java

package demo;

import java.util.Date;

public class SessionContextHolder {
  public Session retrieve() {
    Session session = sessionContext.get();
    if (session == null) {
        return create();
    }
    Date currentTimeStamp = new Date();
    if (new Date().getTime() - session.getTimestamp().getTime() > 3000) {
      sessionContext.remove();
      return create();
    }
    return session;
  }
  
  private Session create() {
    Session session = new Session();
    sessionContext.set(session);
    return session;
  }
}