XPathUtils.java

@UtilityClass
public class XPathUtils {

    public Map<String, Object> extractValue(@NonNull String json, @NonNull String xPath) {
        Map<String, Object> jsonValue = U.fromXmlMap(json);
        return extractValue(jsonValue, xPath);
    }

    @SuppressWarnings("unchecked")
    public Map<String, Object> extractValue(@NonNull Map<String, Object> jsonMap, @NonNull String xPath) {
        Map<String, Object> sourceMap = optimizeMapForXPath(jsonMap);
        JXPathContext context = JXPathContext.newContext(sourceMap);
        return (Map<String, Object>)context.getValue(xPath);
    }

    private Map<String, Object> optimizeMapForXPath(Map<String, Object> jsonMap) {
        Map<String, Object> destination = new LinkedHashMap<>();
        for (Map.Entry<String, Object> entry : jsonMap.entrySet()) {
            String key = entry.getKey();
            Object value = entry.getValue();
            if (value instanceof List) {
                List<LinkedHashMap<String, Object>> sourceMap = (List<LinkedHashMap<String, Object>>) value;
                Map<String, Object> resultMap = new LinkedHashMap<>();
                for (int i = 0; i < sourceMap.size(); i++) {
                    LinkedHashMap<String, Object> map = sourceMap.get(i);
                    resultMap.put(key + i, map);
                }
                destination.put(key, optimizeMapForXPath(resultMap));
            }
            else if (value instanceof String) {
                destination.put(key, value);
            } else if (value instanceof Map) {
                Map<String, Object> resultMap = (Map<String, Object>) value;
                destination.put(key, optimizeMapForXPath(resultMap));
            } else {
                throw new IllegalArgumentException(String.valueOf(value));
            }
        }
        return destination;
    }

}