content: /*
   * 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.beam.sdk.state;
  
  import org.apache.beam.sdk.values.TimestampedValue;
  import org.joda.time.Instant;
  
  /**
   * A {@link ReadableState} cell containing a list of values sorted by timestamp. Timestamped values
   * can be added to the list, and subranges can be read out in order. Subranges of the list can be
   * deleted as well.
   */
  public interface OrderedListState<T>
      extends GroupingState<TimestampedValue<T>, Iterable<TimestampedValue<T>>> {
    /**
     * Read a timestamp-limited subrange of the list. The result is ordered by timestamp.
     *
     * <p>All values with timestamps >= minTimestamp and < limitTimestamp will be in the resuling
     * iterable. This means that only timestamps strictly less than
     * Instant.ofEpochMilli(Long.MAX_VALUE) can be used as timestamps.
     */
    Iterable<TimestampedValue<T>> readRange(Instant minTimestamp, Instant limitTimestamp);
  
    /**
     * Clear a timestamp-limited subrange of the list.
     *
     * <p>All values with timestamps >= minTimestamp and < limitTimestamp will be removed from the
     * list.
     */
    void clearRange(Instant minTimestamp, Instant limitTimestamp);
  
    /**
     * Call to indicate that a specific range will be read from the list, allowing runners to batch
     * multiple range reads.
     */
    OrderedListState<T> readRangeLater(Instant minTimestamp, Instant limitTimestamp);
  }
  