@Override
  public String toString() {
    return "start: " + offset + " end: " + end + " cache buffer: " + getBuffer();
  }
DiskRange containing encoded, uncompressed data from cache.
It should be hidden inside EncodedReaderImpl, but we need to expose it for tests.
ql/src/java/org/apache/hadoop/hive/ql/io/orc/encoded/CacheChunk.java