package com.atlassian.johnson.spring.lifecycle;
   
   import com.atlassian.johnson.spring.web.filter.BypassableDelegatingFilterProxy;
   
   import javax.annotation.Nonnull;
   import javax.servlet.FilterChain;
   import javax.servlet.ServletException;
   import javax.servlet.ServletRequest;
   import javax.servlet.ServletResponse;
  import java.io.IOException;
  
  /**
   * A specialized {@link BypassableDelegatingFilterProxy} for use with the {@link LifecycleDispatcherServlet}. This
   * proxy automatically bypasses the filter when requests are received during application startup.
   *
   * @since 3.0
   */
  public class LifecycleDelegatingFilterProxy extends BypassableDelegatingFilterProxy {
  
      private volatile boolean starting = true;
  
      @Override
      public void doFilter(@Nonnull ServletRequest request, @Nonnull ServletResponse response,
                           @Nonnull FilterChain filterChain) throws ServletException, IOException {
          if (starting) {
              if (LifecycleUtils.isStarting(getServletContext())) {
                  //Otherwise, if the application is still starting, bypass the filter and invoke the chain
                  filterChain.doFilter(request, response);
  
                  return;
              } else {
                  //The first time we see a status other than CREATED or STARTING, note that the application
                  //is no longer starting and apply the filter normally
                  starting = false;
              }
          }
  
          super.doFilter(request, response, filterChain);
      }
  }