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.core.query;
  
  import lombok.Getter;
  import org.apache.skywalking.oap.server.core.Const;
  
  /**
   * PointOfTime represents any point of time based on different precisions.
   */
  @Getter
  public class PointOfTime {
      private long point;
  
      public PointOfTime(long point) {
          this.point = point;
      }
  
      /**
       * @return the row id
       */
      public String id(String entityId) {
          // null means scope = all or unexpected entity.
          if (entityId == null) {
              return String.valueOf(point);
          } else {
              return point + Const.ID_CONNECTOR + entityId;
          }
      }
  }