public static String singleQuote(final String str) {
        if (str == null) {
            return "''";
        } else {
            return "'" + str + "'";
        }
    }
Surrounds str with single quotes. Does not do any escaping. Intended for display purposes.
if str is null returns {@code ''}.
stroom-util-shared/src/main/java/stroom/util/shared/StringUtil.java