nstream.reflect.model.LaneStats Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of nstream-reflect Show documentation
Web Agent introspection runtime
The newest version!
// Copyright 2015-2024 Nstream, inc.
//
// Licensed under the Redis Source Available License 2.0 (RSALv2) Agreement;
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     https://redis.com/legal/rsalv2-agreement/
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package nstream.reflect.model;

import java.util.concurrent.atomic.AtomicLongFieldUpdater;
import swim.structure.Form;
import swim.structure.Item;
import swim.structure.Kind;
import swim.structure.Record;
import swim.structure.Value;
import swim.uri.Uri;

@SuppressWarnings("checkstyle:VisibilityModifier")
public class LaneStats {
  public Uri laneUri;
  public volatile long laneCount;
  public final LinkStats linkStats;

  public LaneStats(Uri laneUri, long laneCount, LinkStats linkStats) {
    this.laneUri = laneUri;
    this.laneCount = laneCount;
    this.linkStats = linkStats;
  }

  public LaneStats(Uri laneUri, LinkStats linkStats) {
    this(laneUri, 0L, linkStats);
  }

  public LaneStats(Uri laneUri) {
    this(laneUri, 0L, new LinkStats());
  }

  public void didOpenLane() {
    LANE_COUNT.incrementAndGet(this);
  }

  public void didCloseLane() {
    LANE_COUNT.decrementAndGet(this);
  }

  public void accumulate(LaneStats lane) {
    LANE_COUNT.addAndGet(this, lane.laneCount);
    this.linkStats.accumulate(lane.linkStats);
  }

  public void supersede(LaneStats total, LaneStats delta) {
    final long newLaneCount = this.laneCount;
    final long oldLaneCount = LANE_COUNT.getAndSet(total, newLaneCount);
    LANE_COUNT.addAndGet(delta, newLaneCount - oldLaneCount);
    this.linkStats.supersede(total.linkStats, total.linkStats);
  }

  public LaneStats getAndReset() {
    final long laneCount = LANE_COUNT.getAndSet(this, 0L);
    return new LaneStats(this.laneUri, laneCount, this.linkStats.getAndReset());
  }

  public LaneStats get() {
    return new LaneStats(this.laneUri, this.laneCount, this.linkStats.get());
  }

  public Value toValue() {
    return form().mold(this).toValue();
  }

  static final AtomicLongFieldUpdater LANE_COUNT =
      AtomicLongFieldUpdater.newUpdater(LaneStats.class, "laneCount");

  private static Form form;

  @Kind
  public static Form form() {
    if (form == null) {
      form = new LaneStatsForm();
    }
    return form;
  }
}

final class LaneStatsForm extends Form {
  @Override
  public String tag() {
    return "lane";
  }

  @Override
  public Class type() {
    return LaneStats.class;
  }

  @Override
  public Item mold(LaneStats stats) {
    if (stats != null) {
      final Record record = Record.create();
      record.attr(tag(), stats.laneUri.toString());
      if (stats.laneCount > 0L) {
        record.slot("laneCount", stats.laneCount);
      }
      record.addAll((Record) stats.linkStats.toValue());
      return record;
    } else {
      return Item.extant();
    }
  }

  @Override
  public LaneStats cast(Item item) {
    final Value value = item.toValue();
    final Value header = value.getAttr(tag());
    if (header.isDefined()) {
      final Uri laneUri = header.coerce(Uri.form());
      final long laneCount = value.get("laneCount").longValue(0L);
      final LinkStats linkStats = LinkStats.form().cast(value);
      return new LaneStats(laneUri, laneCount, linkStats);
    }
    return null;
  }
}