code: @SuppressWarnings({ "rawtypes", "unchecked" })
      public static String join(final Map value, final String delim) {
          if (value == null || value.isEmpty()) {
              return "";
          }
          final StringBuilder buf = new StringBuilder();
          for (final Iterator<Map.Entry<String, String>> i = value.entrySet().iterator(); i.hasNext();) {
              final Map.Entry<String, String> e = i.next();
              buf.append(e.getKey()).append(EQUAL).append(e.getValue());
              if (i.hasNext()) {
                  buf.append(delim);
              }
          }
          return buf.toString();
      }
docs: Assemble all elements in map to a string.
  
  @param value map to serializer
  @param delim entry delimiter
  @return concatenated map