content: /*
   * Copyright 2002-2012 Drew Noakes
   *
   *    Licensed 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.
   *
   * More information about this project is available at:
   *
   *    http://drewnoakes.com/code/exif/
   *    http://code.google.com/p/metadata-extractor/
   */
  package com.almalence.util.exifreader.metadata;
  
  import com.almalence.util.exifreader.lang.BufferReader;
  import com.almalence.util.exifreader.lang.annotations.NotNull;
  
  /**
   * Interface through which all classes responsible for decoding a particular type of metadata may be called.
   * Note that the data source is not specified on this interface.  Instead it is suggested that implementations
   * take their data within a constructor.  Constructors might be overloaded to allow for different sources, such as
   * files, streams and byte arrays.  As such, instances of implementations of this interface would be single-use and
   * not thread-safe.
   *
   * @author Drew Noakes http://drewnoakes.com
   */
  public interface MetadataReader
  {
      /**
       * Extract metadata from the source and merge it into an existing Metadata object.
       *
       * @param reader   The reader from which the metadata should be extracted.
       * @param metadata The Metadata object into which extracted values should be merged.
       */
      public void extract(@NotNull final BufferReader reader, @NotNull final Metadata metadata);
  }
  