String[] roles = { "long_role_" + "a".repeat(50) };
        String[] fields = { "long_field_" + "b".repeat(50) };
        String[] excludes = { "long_exclude_" + "c".repeat(50) };

        String result = popularWordHelper.getCacheKey(seed, tags, roles, fields, excludes);

        assertNotNull(result);
        assertTrue(result.length() > 100);