Method DDFCache

core/src/main/java/io/ddf/DDFCache.java:38–68

(DDFManager manager)

  private DDFManager mDDFManager;

  public DDFCache(DDFManager manager) {

    mDDFManager = manager;

    /**
     * Maximum number of DDFs without name allowed in cache, DDFs will be evicted by an approximate LRU algorithm
     */
    Long maxNumberOfDDFs = Long.valueOf(Config.getGlobalValue(Config.ConfigConstant.MAX_NUMBER_OF_DDFS_IN_CACHE));

    /**
     * Maximum number of DDFs with name allowed in cache, DDFs with name will be evicted by an approximate LRU algorithm
     */
    Long maxNumberOfDDFsWName = Long
        .valueOf(Config.getGlobalValue(Config.ConfigConstant.MAX_NUMBER_OF_DDFS_WITH_NAME_IN_CACHE));

    /**
     * The number of seconds that the DDF will live in cache since it last used(meaning inserted or accessed)
     */
    Long timeToIdle = Long.valueOf(Config.getGlobalValue(Config.ConfigConstant.DDF_TIME_TO_IDLE_SECONDS));

    mLog.info(String.format("Maximum number of ddfs in cache %s", maxNumberOfDDFs));
    mLog.info(String.format("DDF's time to idle = %s seconds", timeToIdle));

    mDDFCache = CacheBuilder.newBuilder().
        maximumSize(maxNumberOfDDFs).expireAfterAccess(timeToIdle, TimeUnit.SECONDS).
        recordStats().removalListener(new DDFRemovalListener()).build();

    // Don't do time based eviction for DDF with name
    mDDFwithNameCache = CacheBuilder.newBuilder().
        maximumSize(maxNumberOfDDFsWName).recordStats().removalListener(new DDFRemovalListener()).build();
  }

  private boolean containsDDF(UUID uuid) {
    return (mDDFCache.asMap().containsKey(uuid) || mDDFwithNameCache.asMap().containsKey(uuid));