code: protected Object getContextAttribute(String name)
      {
          if (ServletHandler.__J_S_CONTEXT_TEMPDIR.equals(name))
          {
              // Initialize temporary directory
              Object t = getHttpContext().getAttribute(ServletHandler.__J_S_CONTEXT_TEMPDIR);
  
              if (t instanceof File)
                  return (File)t;
              
              return getHttpContext().getTempDirectory();
          }
  
          if (_attributes.containsKey(name))
              return _attributes.get(name);
          return getHttpContext().getAttribute(name);
      }
docs: Get context attribute.
  Tries ServletHandler attributes and then delegated to HttpContext.
  @param name attribute name.
  @return attribute