Nutch配置文件的加载

  /* Perform complete crawling and indexing given a set of root urls. */
  public static void main(String args[]) throws Exception {
    if (args.length < 1)
    {
      System.out.println("Usage: Crawl <urlDir> [-dir d] [-threads n] [-depth i] [-topN N] [-r]");
      System.out.println("-r\tremove css and javascript, default is do not remove");
      return;
    }
 
    Configuration conf = NutchConfiguration.create();
    conf.addResource("crawl-tool.xml");
    JobConf job = new NutchJob(conf);

  /** Create a {@link Configuration} for Nutch. */
  public static Configuration create() {
    Configuration conf = new Configuration();
    addNutchResources(conf);
    return conf;
  }

  /** A new configuration. */
  public Configuration() {
    this(true);
  }
 
  /** A new configuration where the behavior of reading from the default 
   * resources can be turned off.
   * 
   * If the parameter {@code loadDefaults} is false, the new instance
   * will not load resources from the default files. 
   * @param loadDefaults specifies whether to load from the default files
   */
  public Configuration(boolean loadDefaults) {
    if (LOG.isDebugEnabled()) {
      LOG.debug(StringUtils.stringifyException(new IOException("config()")));
    }
    if (loadDefaults) {
      resources.add("hadoop-default.xml");
      resources.add("hadoop-site.xml");
    }
  }

  /** Add the standard Nutch resources to {@link Configuration}. */
  public static Configuration addNutchResources(Configuration conf) {
    conf.addResource("nutch-default.xml");
    conf.addResource("nutch-site.xml");
    return conf;
  }