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.kstream.ValueJoiner;
  import org.apache.kafka.streams.state.StoreBuilder;
  
  import java.util.Set;
  
  public abstract class KTableKTableAbstractJoin<K, V1, V2, VOut> implements
      KTableProcessorSupplier<K, V1, K, VOut> {
  
      private final KTableImpl<K, ?, V1> table1;
      private final KTableImpl<K, ?, V2> table2;
      final KTableValueGetterSupplier<K, V1> valueGetterSupplier1;
      final KTableValueGetterSupplier<K, V2> valueGetterSupplier2;
      final ValueJoiner<? super V1, ? super V2, ? extends VOut> joiner;
  
      boolean useVersionedSemantics = false;
      boolean sendOldValues = false;
  
      KTableKTableAbstractJoin(final KTableImpl<K, ?, V1> table1,
                               final KTableImpl<K, ?, V2> table2,
                               final ValueJoiner<? super V1, ? super V2, ? extends VOut> joiner) {
          this.table1 = table1;
          this.table2 = table2;
          this.valueGetterSupplier1 = table1.valueGetterSupplier();
          this.valueGetterSupplier2 = table2.valueGetterSupplier();
          this.joiner = joiner;
      }
  
      @Override
      public final boolean enableSendingOldValues(final boolean forceMaterialization) {
          // Table-table joins require upstream materialization:
          table1.enableSendingOldValues(true);
          table2.enableSendingOldValues(true);
          sendOldValues = true;
          return true;
      }
  
      @Override
      public Set<StoreBuilder<?>> stores() {
          return null;
      }
  
      public void setUseVersionedSemantics(final boolean useVersionedSemantics) {
          this.useVersionedSemantics = useVersionedSemantics;
      }
  
      // VisibleForTesting
      public boolean isUseVersionedSemantics() {
          return useVersionedSemantics;
      }
  
      public String joinThisParentNodeName() {
          return table1.graphNode.nodeName();
      }
  }
  