public String toStringForCache() {
    return "[" + Integer.toHexString(hashCode()) + " " + String.format("%1$.2f", priority) + " "
        + lastUpdate + " " + (isLocked() ? "!" : ".") + "]";
  }
Index in heap for LRFU/LFU cache policies.
llap-server/src/java/org/apache/hadoop/hive/llap/cache/LlapCacheableBuffer.java