code: @Override
      public final void doFilter(final ServletRequest servletRequest, final ServletResponse servletResponse, final FilterChain chain) throws IOException, ServletException {
          if (ProcessingPosition.PRE == this.processingPosition || ProcessingPosition.BOTH == this.processingPosition) {
              this.doProcessing(servletRequest);
          }
  
          chain.doFilter(servletRequest, servletResponse);
  
          if (ProcessingPosition.POST == this.processingPosition || ProcessingPosition.BOTH == this.processingPosition) {
              this.doProcessing(servletRequest);
          }
      }
docs: /* (non-Javadoc)
  @see javax.servlet.Filter#doFilter(javax.servlet.ServletRequest, javax.servlet.ServletResponse, javax.servlet.FilterChain)