iterator.close();
        iterator.close(); // Second close should be safe

        // Then: Tree handle should be released only once
        verify(treeHandle, times(1)).release();
    }

    @Test
    @DisplayName("Iterator should handle filter that rejects all entries")
    void testIterator_FilterRejectsAll() throws Exception {

 * used. HTTP/1.x connections can carry either zero or one streams. HTTP/2 connections can carry any
 * number of streams, dynamically configured with `SETTINGS_MAX_CONCURRENT_STREAMS`. A connection
 * currently carrying zero streams is an idle stream. We keep it alive because reusing an existing
 * connection is typically faster than establishing a new one.
 *

        .addEqualityGroup(Range.all(), Range.all())
        .addEqualityGroup("Phil")
        .testEquals();
  }

  @GwtIncompatible // TODO(b/148207871): Restore once Eclipse compiler no longer flakes for this.
  @J2ktIncompatible // TODO(b/148207871): Likewise, or once J2KT uses javac instead of Eclipse.
  public void testLegacyComparable() {
    Range<LegacyComparable> unused = Range.closed(LegacyComparable.X, LegacyComparable.Y);
  }

```sh
~ mc admin config set alias/ scanner delay=30.0
```

Once set the scanner settings are automatically applied without the need for server restarts.

### Healing

 * retrieval operations obtain elements at the head of the queue.
 *
 * <p>This is a classic &quot;bounded buffer&quot;, in which a fixed-sized array holds elements
 * inserted by producers and extracted by consumers. Once created, the capacity cannot be increased.
 * Attempts to {@code put} an element into a full queue will result in the operation blocking;
 * attempts to {@code take} an element from an empty queue will similarly block.
 *

- [https://hadoop.apache.org/docs/r3.1.1/hadoop-aws/tools/hadoop-aws/committers.html](https://hadoop.apache.org/docs/r3.1.1/hadoop-aws/tools/hadoop-aws/committers.html)

Once the config changes are applied, proceed to restart **Hadoop** services.

![hdfs-services](https://github.com/minio/minio/blob/master/docs/bigdata/images/image7.png?raw=true "hdfs restart services")

// A compacted leaf contains the totals of all files beneath it.
//
// A leaf is only scanned once every dataUsageUpdateDirCycles,
// rarer if the bloom filter for the path is clean and no lifecycles are applied.
// Skipped leaves have their totals transferred from the previous cycle.
//
// When selected there is a one in healObjectSelectProb that any object will be chosen for heal scan.
//
// Compaction happens when either:
//

    int originalSize = collection.size();
    Iterator<E> iterator = collection.iterator();
    Object element = iterator.next();
    // If it's an Entry, it may become invalid once it's removed from the Map. Copy it.
    if (element instanceof Entry) {
      Entry<?, ?> entry = (Entry<?, ?>) element;
      element = mapEntry(entry.getKey(), entry.getValue());
    }

    hasher.putBytes(bytes, off, len);
    out.write(bytes, off, len);
  }

  /**
   * Returns the {@link HashCode} based on the data written to this stream. The result is
   * unspecified if this method is called more than once on the same instance.
   */
  public HashCode hash() {
    return hasher.hash();
  }

  // Overriding close() because FilterOutputStream's close() method pre-JDK8 has bad behavior:

   *
   * [grpc]: https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-HTTP2.md
   */
  open fun isDuplex(): Boolean = false

  /**
   * Returns true if this body expects at most one call to [writeTo] and can be transmitted
   * at most once. This is typically used when writing the request body is destructive and it is not
   * possible to recreate the request body after it has been sent.
   *