code: public static void assertIsExpectedFieldName(final JsonParser parser, final String expectedValue)
              throws JsonParseException, IOException {
          final String actualValue = parser.getCurrentName();
          if (expectedValue == null) {
              if (actualValue != null) {
                  throw new JsonParseException(String.format(SR.UNEXPECTED_FIELD_NAME, expectedValue, actualValue),
                          parser.getCurrentLocation());
              }
          }
          else {
              if (!expectedValue.equals(actualValue)) {
                  throw new JsonParseException(String.format(SR.UNEXPECTED_FIELD_NAME, expectedValue, actualValue),
                          parser.getCurrentLocation());
              }
          }
      }
docs: *
  Reserved for internal use. Asserts that the current name of the parser equals the expected value
  
  @param parser
  The {@link JsonParser} whose current token to check.
  @param expectedValue
  The expected current name of the parser's current token.