code: public Configuration prefixedWith(String... prefixes) {
          if (prefixes == null || prefixes.length == 0) {
              return this;
          }
          Map<String, String> filteredConfig = implementationConfiguration.entrySet().stream()
                  .filter(e -> Arrays.stream(prefixes).anyMatch(p -> e.getKey()
                          .startsWith(p))).collect(toMap(Map.Entry::getKey, Map.Entry::getValue));
          return new Configuration(feedIdStrategy, resultFilter, filteredConfig);
      }
docs: Filters out all the configuration entries whose keys don't start with any of the white-listed prefixes
  
  @param prefixes
  @return