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.restapi;
  
  import java.util.List;
  import java.util.stream.Collectors;
  import com.fasterxml.jackson.annotation.JsonTypeInfo;
  import org.apache.skywalking.apm.network.common.v3.KeyStringValuePair;
  import org.apache.skywalking.apm.network.language.agent.v3.SpanLayer;
  import org.apache.skywalking.apm.network.language.agent.v3.SpanObject;
  import org.apache.skywalking.generator.Generator;
  import lombok.Getter;
  import lombok.Setter;
  
  @Getter
  @Setter
  @JsonTypeInfo(use = JsonTypeInfo.Id.NONE)
  public final class SpanGenerator implements Generator<SpanObject> {
      private Generator<Long> spanId;
      private Generator<Long> parentSpanId;
      private Generator<Long> startTime;
      private Generator<Long> endTime;
      private Generator<String> operationName;
      private Generator<String> peer;
      private Generator<Long> spanLayer;
      private Generator<Long> componentId;
      private Generator<Boolean> error;
      private Generator<List<TagGenerator>> tags;
  
      @Override
      public SpanObject next() {
          return SpanObject
              .newBuilder()
              .setSpanId(getSpanId().next().intValue())
              .setParentSpanId(getParentSpanId().next().intValue())
              .setStartTime(getStartTime().next())
              .setEndTime(getEndTime().next())
              .setOperationName(getOperationName().next())
              .setPeer(getPeer().next())
              .setSpanLayer(SpanLayer.forNumber(getSpanLayer().next().intValue()))
              .setComponentId(getComponentId().next().intValue())
              .setIsError(getError().next())
              .addAllTags(
                  getTags()
                      .next()
                      .stream()
                      .map(TagGenerator::next)
                      .map(it -> KeyStringValuePair
                          .newBuilder().setKey(it.getKey())
                          .setValue(it.getValue()).build())
                      .collect(Collectors.toList()))
              .build();
      }
  
      @Override
      public void reset() {
          spanId.reset();
          parentSpanId.reset();
          startTime.reset();
          endTime.reset();
          operationName.reset();
          peer.reset();
          spanLayer.reset();
          componentId.reset();
          error.reset();
          tags.reset();
      }
  }
  