private void loadResource()

in odps-sdk/odps-sdk-commons/src/main/java/com/aliyun/odps/conf/Configuration.java [1021:1144]
113 lines of code
35 McCabe index (conditional complexity)

  private void loadResource(Properties properties, Object name, boolean quiet) {
    try {
      DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory.newInstance();
      docBuilderFactory.setFeature("http://apache.org/xml/features/disallow-doctype-decl", true);
      docBuilderFactory.setFeature("http://xml.org/sax/features/external-general-entities", false);
      docBuilderFactory.setFeature("http://xml.org/sax/features/external-parameter-entities", false);

      // 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;

      if (name instanceof URL) { // an URL resource
        URL url = (URL) name;
        if (url != null) {
          if (!quiet) {
            LOG.info("parsing " + url);
          }
          doc = builder.parse(url.toString());
        }
      } else if (name instanceof String) { // a CLASSPATH resource
        URL url = getResource((String) name);
        if (url != null) {
          if (!quiet) {
            LOG.info("parsing " + url);
          }
          doc = builder.parse(url.toString());
        }
      } else if (name instanceof InputStream) {
        try {
          doc = builder.parse((InputStream) name);
        } finally {
          ((InputStream) name).close();
        }
      } else if (name instanceof Element) {
        root = (Element) name;
      }

      if (doc == null && root == null) {
        if (quiet) {
          return;
        }
        throw new RuntimeException(name + " not found");
      }

      if (root == null) {
        root = doc.getDocumentElement();
      }
      if (!"configuration".equals(root.getTagName())) {
        LOG.fatal("bad conf file: top-level element not <configuration>");
      }
      NodeList props = root.getChildNodes();
      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(properties, prop, 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;
        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 = ((Text) field.getFirstChild()).getData().trim();
          }
          if ("value".equals(field.getTagName()) && field.hasChildNodes()) {
            value = ((Text) field.getFirstChild()).getData();
          }
          if ("final".equals(field.getTagName()) && field.hasChildNodes()) {
            finalParameter = "true".equals(((Text) field.getFirstChild()).getData());
          }
        }

        // Ignore this parameter if it has already been marked as
        // 'final'
        if (attr != null && value != null) {
          if (!finalParameters.contains(attr)) {
            properties.setProperty(attr, value);
            if (finalParameter) {
              finalParameters.add(attr);
            }
          } else {
            LOG.warn(name + ":a attempt to override final parameter: " + attr + ";  Ignoring.");
          }
        }
      }

    } catch (IOException e) {
      LOG.fatal("error parsing conf file: " + e);
      throw new RuntimeException(e);
    } catch (DOMException e) {
      LOG.fatal("error parsing conf file: " + e);
      throw new RuntimeException(e);
    } catch (SAXException e) {
      LOG.fatal("error parsing conf file: " + e);
      throw new RuntimeException(e);
    } catch (ParserConfigurationException e) {
      LOG.fatal("error parsing conf file: " + e);
      throw new RuntimeException(e);
    }
  }