code: /**
   * 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.nutch.metadata;
  
  import org.apache.hadoop.io.Text;
  
  
  /**
   * A collection of Nutch internal metadata constants.
   *
   * @author Chris Mattmann
   * @author J&eacute;r&ocirc;me Charron
   */
  public interface Nutch {
    
    public static final String ORIGINAL_CHAR_ENCODING =
            "OriginalCharEncoding";
    
    public static final String CHAR_ENCODING_FOR_CONVERSION =
            "CharEncodingForConversion";
  
    public static final String SIGNATURE_KEY = "nutch.content.digest";
  
    public static final String SEGMENT_NAME_KEY = "nutch.segment.name";
  
    public static final String SCORE_KEY = "nutch.crawl.score";
  
    public static final String GENERATE_TIME_KEY = "_ngt_";
  
    public static final Text WRITABLE_GENERATE_TIME_KEY = new Text(GENERATE_TIME_KEY);
  
    public static final String PROTO_STATUS_KEY = "_pst_";
  
    public static final Text WRITABLE_PROTO_STATUS_KEY = new Text(PROTO_STATUS_KEY);
    
    public static final String FETCH_TIME_KEY = "_ftk_";
    
    public static final String FETCH_STATUS_KEY = "_fst_";
  
    /** Sites may request that search engines don't provide access to cached documents. */
    public static final String CACHING_FORBIDDEN_KEY = "caching.forbidden";
  
    /** Show both original forbidden content and summaries (default). */
    public static final String CACHING_FORBIDDEN_NONE = "none";
  
    /** Don't show either original forbidden content or summaries. */
    public static final String CACHING_FORBIDDEN_ALL = "all";
  
    /** Don't show original forbidden content, but show summaries. */
    public static final String CACHING_FORBIDDEN_CONTENT = "content";
  
    public static final String REPR_URL_KEY = "_repr_";
  
    public static final Text WRITABLE_REPR_URL_KEY = new Text(REPR_URL_KEY);
  }
  