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
   * <p/>
   * http://www.apache.org/licenses/LICENSE-2.0
   * <p/>
   * 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 storm.trident.windowing;
  
  import com.google.common.base.Preconditions;
  
  import java.io.Serializable;
  import java.util.Collection;
  import java.util.List;
  
  /**
   * Store for storing window related entities like windowed tuples, triggers etc.
   */
  public interface WindowsStore extends Serializable {
  
      /**
       * This can be used as a separator while generating a key from sequence of strings.
       */
      String KEY_SEPARATOR = "|";
  
      Object get(String key);
  
      Iterable<Object> get(List<String> keys);
  
      Iterable<String> getAllKeys();
  
      void put(String key, Object value);
  
      void putAll(Collection<Entry> entries);
  
      void remove(String key);
  
      void removeAll(Collection<String> keys);
  
      void shutdown();
  
      /**
       * This class wraps key and value objects which can be passed to {@code putAll} method.
       */
      class Entry implements Serializable {
          public final String key;
          public final Object value;
  
          public Entry(String key, Object value) {
              nonNullCheckForKey(key);
              nonNullCheckForValue(value);
              this.key = key;
              this.value = value;
          }
  
          public static void nonNullCheckForKey(Object key) {
              Preconditions.checkArgument(key != null, "key argument can not be null");
          }
  
          public static void nonNullCheckForValue(Object value) {
              Preconditions.checkArgument(value != null, "value argument can not be null");
          }
  
      }
  
  }
  