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.kafka.streams.kstream.internals;
  
  import org.apache.kafka.streams.processor.StateStore;
  import org.apache.kafka.streams.processor.api.ProcessorContext;
  import org.apache.kafka.streams.processor.api.Record;
  import org.apache.kafka.streams.processor.internals.InternalProcessorContext;
  import org.apache.kafka.streams.state.internals.CacheFlushListener;
  import org.apache.kafka.streams.state.internals.WrappedStateStore;
  
  /**
   * This class is used to determine if a processor should forward values to child nodes.
   * Forwarding by this class only occurs when caching is not enabled. If caching is enabled,
   * forwarding occurs in the flush listener when the cached store flushes.
   *
   * @param <K> the type of the key
   * @param <V> the type of the value
   */
  class TimestampedTupleForwarder<K, V> {
      private final InternalProcessorContext<K, Change<V>> context;
      private final boolean sendOldValues;
      private final boolean cachingEnabled;
  
      @SuppressWarnings({"unchecked", "rawtypes"})
      TimestampedTupleForwarder(final StateStore store,
                                final ProcessorContext<K, Change<V>> context,
                                final CacheFlushListener<K, ?> flushListener,
                                final boolean sendOldValues) {
          this.context = (InternalProcessorContext<K, Change<V>>) context;
          this.sendOldValues = sendOldValues;
          cachingEnabled = ((WrappedStateStore) store).setFlushListener(flushListener, sendOldValues);
      }
  
      TimestampedTupleForwarder(final ProcessorContext<K, Change<V>> context,
                                final boolean sendOldValues) {
          this.context = (InternalProcessorContext<K, Change<V>>) context;
          this.sendOldValues = sendOldValues;
          cachingEnabled = false;
      }
  
      public void maybeForward(final Record<K, Change<V>> record) {
          if (!cachingEnabled) {
              if (sendOldValues) {
                  context.forward(record);
              } else {
                  context.forward(record.withValue(new Change<>(record.value().newValue, null, record.value().isLatest)));
              }
          }
      }
  }
  