Method loadCachedJson

src/tsd/GraphHandler.java:643–662

Attempts to read the cached .json file for this query. @param query The query to serve. @param end_time The end time on the query (32-bit unsigned int, seconds). @param max_age The maximum time (in seconds) we wanna allow clients to cache the result in case of a cache hit. @param basepath Th

(final HttpQuery query,
                                       final long end_time,
                                       final long max_age,
                                       final String basepath)

   * @throws JsonParseException If the JSON is improperly formatted
   */
  @SuppressWarnings("unchecked")
  private HashMap<String, Object> loadCachedJson(final HttpQuery query,
                                       final long end_time,
                                       final long max_age,
                                       final String basepath)
                                       throws JsonParseException,
                                       JsonMappingException, IOException {
    final String json_path = basepath + ".json";
    File json_cache = new File(json_path);
    if (staleCacheFile(query, end_time, max_age, json_cache)) {
      return null;
    }
    final byte[] json = readFile(query, json_cache, 4096);
    if (json == null) {
      return null;
    }
    json_cache = null;

    return (HashMap<String, Object>) JSON.parseToObject(json, HashMap.class);
  }

  /** Parses the {@code wxh} query parameter to set the graph dimension. */
  static void setPlotDimensions(final HttpQuery query, final Plot plot) {