default List<String> extractParams(final String rule) {
        List<String> params = new ArrayList<>();
        String[] split = rule.split("(?<!\\\\)\\|");
        if (split.length >= getParamSize() + 1) {
            params.addAll(Arrays.stream(split)
                    .map(p -> p.replaceAll("\\\\\\|", "|"))
                    .skip(1)
                    .collect(Collectors.toList()));
        }
        return params;
    }
extract params from rule.

@param rule rule
@return params
shenyu-plugin/shenyu-plugin-mock/src/main/java/org/apache/shenyu/plugin/mock/generator/Generator.java