code: private String getContentHandlerPkgPrefixes() {
          String packagePrefixList = System.getProperty(contentPathProp, "");
  
          if (packagePrefixList != "") {
              packagePrefixList += "|";
          }
  
          return packagePrefixList + contentClassPrefix;
      }
docs: Returns a vertical bar separated list of package prefixes for potential
  content handlers.  Tries to get the java.content.handler.pkgs property
  to use as a set of package prefixes to search.  Whether or not
  that property has been defined, the sun.net.www.content is always
  the last one on the returned package list.