void parseAppenderFilters()

in src/main/java/org/apache/log4j/PropertyConfigurator.java [876:932]
51 lines of code
10 McCabe index (conditional complexity)

  void parseAppenderFilters(Properties props, String appenderName, Appender appender) {
    // extract filters and filter options from props into a hashtable mapping
    // the property name defining the filter class to a list of pre-parsed
    // name-value pairs associated to that filter
    final String filterPrefix = APPENDER_PREFIX + appenderName + ".filter.";
    int fIdx = filterPrefix.length();
    Hashtable filters = new Hashtable();
    Enumeration e = props.keys();
    String name = "";
    while (e.hasMoreElements()) {
      String key = (String) e.nextElement();
      if (key.startsWith(filterPrefix)) {
        int dotIdx = key.indexOf('.', fIdx);
        String filterKey = key;
        if (dotIdx != -1) {
          filterKey = key.substring(0, dotIdx);
          name = key.substring(dotIdx+1);
        }
        Vector filterOpts = (Vector) filters.get(filterKey);
        if (filterOpts == null) {
          filterOpts = new Vector();
          filters.put(filterKey, filterOpts);
        }
        if (dotIdx != -1) {
          String value = OptionConverter.findAndSubst(key, props);
          filterOpts.add(new NameValue(name, value));
        }
      }
    }

    // sort filters by IDs, insantiate filters, set filter options,
    // add filters to the appender
    Enumeration g = new SortedKeyEnumeration(filters);
    while (g.hasMoreElements()) {
      String key = (String) g.nextElement();
      String clazz = props.getProperty(key);
      if (clazz != null) {
        LogLog.debug("Filter key: ["+key+"] class: ["+props.getProperty(key) +"] props: "+filters.get(key));
        Filter filter = (Filter) OptionConverter.instantiateByClassName(clazz, Filter.class, null);
        if (filter != null) {
          PropertySetter propSetter = new PropertySetter(filter);
          Vector v = (Vector)filters.get(key);
          Enumeration filterProps = v.elements();
          while (filterProps.hasMoreElements()) {
            NameValue kv = (NameValue)filterProps.nextElement();
            propSetter.setProperty(kv.key, kv.value);
          }
          propSetter.activate();
          LogLog.debug("Adding filter of type ["+filter.getClass()
           +"] to appender named ["+appender.getName()+"].");
          appender.addFilter(filter);
        }
      } else {
        LogLog.warn("Missing class definition for filter: ["+key+"]");
      }
    }
  }