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.test;
  
  import org.apache.kafka.common.serialization.Serializer;
  import org.apache.kafka.streams.processor.StateStore;
  import org.apache.kafka.streams.processor.StateStoreContext;
  import org.apache.kafka.streams.query.Position;
  import org.apache.kafka.streams.state.KeyValueIterator;
  import org.apache.kafka.streams.state.ReadOnlyKeyValueStore;
  
  import java.io.File;
  
  public class NoOpReadOnlyStore<K, V> implements ReadOnlyKeyValueStore<K, V>, StateStore {
      private final String name;
      private final boolean rocksdbStore;
      private boolean open = true;
      public boolean initialized;
      public boolean flushed;
  
      public NoOpReadOnlyStore() {
          this("", false);
      }
  
      public NoOpReadOnlyStore(final String name) {
          this(name, false);
      }
  
      public NoOpReadOnlyStore(final String name,
                               final boolean rocksdbStore) {
          this.name = name;
          this.rocksdbStore = rocksdbStore;
      }
  
      @Override
      public V get(final K key) {
          return null;
      }
  
      @Override
      public KeyValueIterator<K, V> range(final K from, final K to) {
          return null;
      }
  
      @Override
      public <PS extends Serializer<P>, P> KeyValueIterator<K, V> prefixScan(P prefix, PS prefixKeySerializer) {
          return null;
      }
  
      @Override
      public KeyValueIterator<K, V> all() {
          return null;
      }
  
      @Override
      public long approximateNumEntries() {
          return 0L;
      }
  
      @Override
      public String name() {
          return name;
      }
  
      @Override
      public void init(final StateStoreContext stateStoreContext, final StateStore root) {
          if (rocksdbStore) {
              // cf. RocksDBStore
              new File(stateStoreContext.stateDir() + File.separator + "rocksdb" + File.separator + name).mkdirs();
          } else {
              new File(stateStoreContext.stateDir() + File.separator + name).mkdir();
          }
          this.initialized = true;
          stateStoreContext.register(root, (k, v) -> { });
      }
  
      @Override
      public void flush() {
          flushed = true;
      }
  
      @Override
      public void close() {
          open = false;
      }
  
      @Override
      public boolean persistent() {
          return rocksdbStore;
      }
  
      @Override
      public boolean isOpen() {
          return open;
      }
  
      @Override
      public Position getPosition() {
          throw new UnsupportedOperationException("Position handling not implemented");
      }
  
  }
  