Utils.cls

public with sharing class Utils {
    
    //If parser is at start of inner object or array, skipping till end of the section
    public static JSONParser skipTillEndOfSection(JSONParser parser) {
        if(parser != null && parser.getCurrentToken() == JSONToken.START_ARRAY) {
            if(parser.getCurrentToken() == JSONToken.START_ARRAY) {
                while(parser.getCurrentToken() != JSONToken.END_ARRAY) {
                    parser.nextToken();
                    if(parser.getCurrentToken() == JSONToken.START_ARRAY ||  parser.getCurrentToken() == JSONToken.START_OBJECT) {
                        skipTillEndOfSection(parser);
                    }
                }
            }else if(parser.getCurrentToken() == JSONToken.START_OBJECT) {
                while(parser.getCurrentToken() != JSONToken.END_OBJECT) {
                    parser.nextToken();
                    if(parser.getCurrentToken() == JSONToken.START_ARRAY ||  parser.getCurrentToken() == JSONToken.START_OBJECT) {
                        skipTillEndOfSection(parser);
                    }
                }
            }
        }
        return parser;
    }
    
    /**************************************************************************************
    * @Description  This method extract value of inner attributes in a JSON
    * @Param		String - JSON string
    * @Param		String - JSON attribute path
    * @Return       String - This sample assumes returned value is a string
    * @Example     
    * Utils.extractAttributeFromJson('{"data":{"user":{"organization":{"id":"123"}}}}', 'data.user.organization.id');
    **************************************************************************************/
    public static String extractAttributeFromJson(String jsonResponse, String attrString) {
        if(String.isBlank(jsonResponse) || String.isBlank(attrString)) return null;
        List<String> attrPath = attrString.split('\\.');
        JSONParser parser = JSON.createParser(jsonResponse);
        Integer index = 0;
        parser.nextToken();
        while(parser.nextToken() != null) {
            if (parser.getCurrentToken() == JSONToken.FIELD_NAME) {
                if(attrPath[index] == parser.getText()) {
                    if(index == attrPath.size()-1) {
                        parser.nextToken();
                        return parser.getText();
                    }else if(parser.nextToken() == JSONToken.START_OBJECT) {
                        index++;
                    }
                }
            }else if(parser.getCurrentToken() == JSONToken.START_OBJECT || parser.getCurrentToken() == JSONToken.START_ARRAY) {
                skipTillEndOfSection(parser);
            }
        }
        return null;
    }
}