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.state.internals;
  
  import org.apache.kafka.streams.StoreQueryParameters;
  import org.apache.kafka.streams.processor.StateStore;
  import org.apache.kafka.streams.state.QueryableStoreType;
  
  import java.util.List;
  import java.util.Map;
  import java.util.concurrent.ConcurrentHashMap;
  
  /**
   * A wrapper over all of the {@link StateStoreProvider}s in a Topology
   *
   * The store providers field is a reference
   */
  public class QueryableStoreProvider {
  
      // map of StreamThread.name to StreamThreadStateStoreProvider
      private final Map<String, StreamThreadStateStoreProvider> storeProviders;
      private final GlobalStateStoreProvider globalStoreProvider;
  
      public QueryableStoreProvider(final GlobalStateStoreProvider globalStateStoreProvider) {
          this.storeProviders = new ConcurrentHashMap<>();
          this.globalStoreProvider = globalStateStoreProvider;
      }
  
      /**
       * Get a composite object wrapping the instances of the {@link StateStore} with the provided
       * storeName and {@link QueryableStoreType}
       *
       * @param storeQueryParameters       if stateStoresEnabled is used i.e. staleStoresEnabled is true, include standbys and recovering stores;
       *                                        if stateStoresDisabled i.e. staleStoresEnabled is false, only include running actives;
       *                                        if partition is null then it fetches all local partitions on the instance;
       *                                        if partition is set then it fetches a specific partition.
       * @param <T>                The expected type of the returned store
       * @return A composite object that wraps the store instances.
       */
      public <T> T store(final StoreQueryParameters<T> storeQueryParameters) {
          final String storeName = storeQueryParameters.storeName();
          final QueryableStoreType<T> queryableStoreType = storeQueryParameters.queryableStoreType();
          final List<T> globalStore = globalStoreProvider.stores(storeName, queryableStoreType);
          if (!globalStore.isEmpty()) {
              return queryableStoreType.create(globalStoreProvider, storeName);
          }
          return queryableStoreType.create(
              new WrappingStoreProvider(storeProviders.values(), storeQueryParameters),
              storeName
          );
      }
  
      public void addStoreProviderForThread(final String threadName, final StreamThreadStateStoreProvider streamThreadStateStoreProvider) {
          this.storeProviders.put(threadName, streamThreadStateStoreProvider);
      }
  
      public void removeStoreProviderForThread(final String threadName) {
          this.storeProviders.remove(threadName);
      }
  }
  