code: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You under the Apache License, Version 2.0
   * (the "License"); you may not use this file except in compliance with
   * the License.  You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * 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 org.apache.skywalking.oap.server.analyzer.provider.trace.parser.listener;
  
  import lombok.RequiredArgsConstructor;
  import org.apache.skywalking.apm.network.language.agent.v3.SegmentObject;
  import org.apache.skywalking.oap.server.analyzer.provider.trace.TraceSamplingPolicyWatcher;
  
  /**
   * The sampler makes the sampling mechanism works at backend side. Sample result: [0,sampleRate) sampled, (sampleRate,~)
   * ignored
   */
  @RequiredArgsConstructor
  public class TraceSegmentSampler {
      private final TraceSamplingPolicyWatcher traceSamplingPolicyWatcher;
  
      public boolean shouldSample(SegmentObject segmentObject, int duration) {
          int sample = Math.abs(segmentObject.getTraceId().hashCode()) % 10000;
          String serviceName = segmentObject.getService();
          return traceSamplingPolicyWatcher.shouldSample(serviceName, sample, duration);
      }
  
  }
  