private List<String> searchSubstring(String word, int field) {
        List<String> result = new ArrayList<>();
        String[] words = fieldWords[field];
        for (String s : words) {
            String tempWord = s;
            int index = tempWord.indexOf("_");
            if (index != -1) {
                tempWord = tempWord.substring(index + 1);
            }
            if (word != null && word.toLowerCase().equals(tempWord)) {
                result.add(tempWord);
            }
        }
        return result;
    }
Extract the information from links as word in the URL, anchor and around links, and converts
it to an Instance object

@param linkNeighboors The LinkNeighborhood instances to be converted to Instance
@param features String[] pre-defined words
@return HashMap mapping url -> instance
ache/src/main/java/achecrawler/link/classifier/builder/LinkNeighborhoodWrapper.java