private Resource loadResource()

in flink-filesystems/flink-swift-fs-hadoop/src/main/java/org/apache/hadoop/conf/Configuration.java [2526:2667]
130 lines of code
37 McCabe index (conditional complexity)

  private Resource loadResource(Properties properties, Resource wrapper, boolean quiet) {
    String name = UNKNOWN_RESOURCE;
    try {
      Object resource = wrapper.getResource();
      name = wrapper.getName();

      DocumentBuilderFactory docBuilderFactory
        = DocumentBuilderFactory.newInstance();
      //ignore all comments inside the xml file
      docBuilderFactory.setIgnoringComments(true);

      //allow includes in the xml file
      docBuilderFactory.setNamespaceAware(true);
      try {
          docBuilderFactory.setXIncludeAware(true);
      } catch (UnsupportedOperationException e) {
        LOG.error("Failed to set setXIncludeAware(true) for parser "
                + docBuilderFactory
                + ":" + e,
                e);
      }
      DocumentBuilder builder = docBuilderFactory.newDocumentBuilder();
      Document doc = null;
      Element root = null;
      boolean returnCachedProperties = false;

      if (resource instanceof URL) {                  // an URL resource
        doc = parse(builder, (URL)resource);
      } else if (resource instanceof String) {        // a CLASSPATH resource
        URL url = getResource((String)resource);
        doc = parse(builder, url);
      } else if (resource instanceof Path) {          // a file resource
        // Can't use FileSystem API or we get an infinite loop
        // since FileSystem uses Configuration API.  Use java.io.File instead.
        File file = new File(((Path)resource).toUri().getPath())
          .getAbsoluteFile();
        if (file.exists()) {
          if (!quiet) {
            LOG.debug("parsing File " + file);
          }
          doc = parse(builder, new BufferedInputStream(
              new FileInputStream(file)), ((Path)resource).toString());
        }
      } else if (resource instanceof InputStream) {
        doc = parse(builder, (InputStream) resource, null);
        returnCachedProperties = true;
      } else if (resource instanceof Properties) {
        overlay(properties, (Properties)resource);
      } else if (resource instanceof Element) {
        root = (Element)resource;
      }

      if (root == null) {
        if (doc == null) {
          if (quiet) {
            return null;
          }
          throw new RuntimeException(resource + " not found");
        }
        root = doc.getDocumentElement();
      }
      Properties toAddTo = properties;
      if(returnCachedProperties) {
        toAddTo = new Properties();
      }
      if (!"configuration".equals(root.getTagName()))
        LOG.fatal("bad conf file: top-level element not <configuration>");
      NodeList props = root.getChildNodes();
      DeprecationContext deprecations = deprecationContext.get();
      for (int i = 0; i < props.getLength(); i++) {
        Node propNode = props.item(i);
        if (!(propNode instanceof Element))
          continue;
        Element prop = (Element)propNode;
        if ("configuration".equals(prop.getTagName())) {
          loadResource(toAddTo, new Resource(prop, name), quiet);
          continue;
        }
        if (!"property".equals(prop.getTagName()))
          LOG.warn("bad conf file: element not <property>");
        NodeList fields = prop.getChildNodes();
        String attr = null;
        String value = null;
        boolean finalParameter = false;
        LinkedList<String> source = new LinkedList<String>();
        for (int j = 0; j < fields.getLength(); j++) {
          Node fieldNode = fields.item(j);
          if (!(fieldNode instanceof Element))
            continue;
          Element field = (Element)fieldNode;
          if ("name".equals(field.getTagName()) && field.hasChildNodes())
            attr = StringInterner.weakIntern(
                ((Text)field.getFirstChild()).getData().trim());
          if ("value".equals(field.getTagName()) && field.hasChildNodes())
            value = StringInterner.weakIntern(
                ((Text)field.getFirstChild()).getData());
          if ("final".equals(field.getTagName()) && field.hasChildNodes())
            finalParameter = "true".equals(((Text)field.getFirstChild()).getData());
          if ("source".equals(field.getTagName()) && field.hasChildNodes())
            source.add(StringInterner.weakIntern(
                ((Text)field.getFirstChild()).getData()));
        }
        source.add(name);

        // Ignore this parameter if it has already been marked as 'final'
        if (attr != null) {
          if (deprecations.getDeprecatedKeyMap().containsKey(attr)) {
            DeprecatedKeyInfo keyInfo =
                deprecations.getDeprecatedKeyMap().get(attr);
            keyInfo.clearAccessed();
            for (String key:keyInfo.newKeys) {
              // update new keys with deprecated key's value
              loadProperty(toAddTo, name, key, value, finalParameter,
                  source.toArray(new String[source.size()]));
            }
          }
          else {
            loadProperty(toAddTo, name, attr, value, finalParameter,
                source.toArray(new String[source.size()]));
          }
        }
      }

      if (returnCachedProperties) {
        overlay(properties, toAddTo);
        return new Resource(toAddTo, name);
      }
      return null;
    } catch (IOException e) {
      LOG.fatal("error parsing conf " + name, e);
      throw new RuntimeException(e);
    } catch (DOMException e) {
      LOG.fatal("error parsing conf " + name, e);
      throw new RuntimeException(e);
    } catch (SAXException e) {
      LOG.fatal("error parsing conf " + name, e);
      throw new RuntimeException(e);
    } catch (ParserConfigurationException e) {
      LOG.fatal("error parsing conf " + name , e);
      throw new RuntimeException(e);
    }
  }