private long sublong(String value, int beginIndex, int endIndex) {
        String substring = value.substring(beginIndex, endIndex);
        return (substring.length() > 0) ? Long.parseLong(substring) : -1;
    }
Returns a substring of the given string value from the given begin index to the given end
index as a long. If the substring is empty, then -1 will be returned

@param value      The string value to return a substring as long for.
@param beginIndex The begin index of the substring to be returned as long.
@param endIndex   The end index of the substring to be returned as long.
@return A substring of the given string value as long or -1 if substring is empty.
src/main/java/com/kodedu/controller/CacheResource.java