xmlutils.java

Oracle的J2EE Sample

   * Parses the string representation,validates with the given schema file
   * and returns the XML Document.
   *
   * @param xmlStr string representaion of the XML Document
   * @param url url of schema file
   * @return XML Document constructed from the string
   * @since 1.0
   */
  public static Document stringToXML(String xmlStr, String url) {

    // Initialize DOM Parser
    DOMParser dp     = new DOMParser();
    Document  xmldoc = null;

    // Set Schema Object for Validation
    dp.setXMLSchema(getXMLSchema(url));
    dp.setValidationMode(XMLParser.SCHEMA_VALIDATION);
    dp.setPreserveWhitespace(true);

    try {

      // Parse the file through the Reader instance and validate with
      // schema object
      StringReader input = new StringReader(xmlStr);
      dp.parse(input);

      // Get the Root element of the parsed document
      xmldoc = dp.getDocument();
    } catch (XMLParseException pe) {
      System.out.println("Parser Exception: " + pe.toString());
    } catch (Exception e) {
      System.out.println("NonParserException: " + e.toString());
    }

    return xmldoc;
  }
}  // End of class - XMLUtils

/**
 * This class extends the DefaultHandler class and overrides
 * the standard callback methods. This class parses the given XML file
 * and populates the URLMappings in a Hashmap.
 *
 * @version 1.0
 * @since 1.0
 */
class URLMappingHandler extends DefaultHandler {

  // Hashmap to hold URLMappings
  private HashMap hmap = new HashMap();

  // Instance of URLMap, currently being populated.
  private URLMapping urlMap = null;

  // Name of the last tag encountered by startElement(..) method
  private String lastTag = null;

  // List of roles for the current URLMap
  private ArrayList roles = new ArrayList();

  /**
   * Returns the mappings that have been parsed and loaded in Hashmap.
   *
   * @return HashMap containing URLMappings.
   * @since 1.0
   */
  public HashMap getMappings() {
    return hmap;
  }

  /**
   * Clears the Hashmap.
   *
   * @since 1.0
   */
  public void clearMappings() {
    hmap.clear();
  }

  /**
   * This method is notified when a start tag is encountered.
   *
   * @param namespaceURI namespace URI
   * @param sName local name of the tag
   * @param qName quantified name of the tag
   * @param attrs Attribute list of the tag
   * @since 1.0
   */
  public void startElement(String namespaceURI, String sName, String qName,
                           Attributes attrs) {

    String tagName = sName;

    // If Namespace aware
    if ("".equals(sName) || (sName == null)) {
      tagName = qName;
    }

    // A new event was encountered, initialize a new URLMapping
    if (tagName.equals("Event")) {

      // Start a new URL Mapping
      urlMap = new URLMapping();

    } else {
      lastTag = tagName;
    }


  }

  /**
   * This method is notified when a end tag is encountered.
   *
   * @param namespaceURI namespace URI
   * @param sName local name of the tag
   * @param qName quantified name of the tag
   * @since 1.0
   */
  public void endElement(String namespaceURI, String sName, String qName) {

    String tagName = sName;

    // If namespace aware
    if ("".equals(sName) || (sName == null)) {
      tagName = qName;
    }

    // If end of a URL mapping
    if (tagName.equals("Event")) {

      // Put the  URL Mapping into the Hashmap
      hmap.put(urlMap.getEventName(), urlMap);

    } else if (tagName.equals("Roles")) {

        // Load the roles into the URLMap
        String[] role = (String[]) roles.toArray(new String[roles.size()]);
        urlMap.setRoles(role);
        roles.clear();

    }
    // Reset last tag
    lastTag = null;

  }

  /**
   * This method is notified when the characters in-between tags is encountered.
   *
   * @param ch Character array of the text
   * @param offset start position in the char array
   * @param len length of the characters to be taken from the char array
   * @since 1.0
   */
  public void characters(char[] ch, int offset, int len) {

    if (len == 0 || lastTag==null)   return;

    String tagValue = new String(ch, offset, len);

    if (lastTag.equals("Name"))

      urlMap.setEventName(tagValue);

    else if (lastTag.equals("Class"))

      urlMap.setClassName(tagValue);

    else if (lastTag.equals("Method"))

      urlMap.setMethodName(tagValue);

    else if (lastTag.equals("Screen"))

      urlMap.setNextScreen(tagValue);

    else if (lastTag.equals("Role"))
      roles.add(tagValue);

  }

}  // End of class URLMappingHandler

/**
 * This class extends the DefaultHandler class and overrides
 * the standard callback methods. This class parses the given XML file
 * and populates the ExceptionMappings in a Hashmap.
 *
 * @version 1.0
 * @since 1.0
 */
class ExceptionMappingHandler extends DefaultHandler {

  // Hashmap to hold ExceptionMappings
  private HashMap hmap = new HashMap();

  // ExceptionMap that is currently being constructed
  private ExceptionMapping excpMap = null;

  // Name of the last tag encountered by startElement(..)
  private String lastTag = null;

  /**
   * Returns the mappings that have been parsed and loaded in Hashmap.
   *
   * @return HashMap containing ExceptionMappings.
   * @since 1.0
   */
  public HashMap getMappings() {
    return hmap;
  }

  /**
   * Clears the Hashmap.
   *
   * @since 1.0
   */
  public void clearMappings() {
    hmap.clear();
  }

  /**
   * This method is notified when a start tag is encountered.
   *
   * @param namespaceURI namespace URI
   * @param sName local name of the tag
   * @param qName quantified name of the tag
   * @param attrs Attribute list of the tag
   * @since 1.0
   */
  public void startElement(String namespaceURI, String sName, String qName,
                           Attributes attrs) {

    String tagName = sName;
    if ("".equals(sName) || (sName == null)) {
      tagName = qName;
    }

    if (tagName.equals("Exception")) {

      // Start a new Exception Mapping
      excpMap = new ExceptionMapping();
    }
    else {
      lastTag = tagName;
    }
  }

  /**
   * This method is notified when a end tag is encountered.
   *
   * @param namespaceURI namespace URI
   * @param sName local name of the tag
   * @param qName quantified name of the tag
   * @since 1.0
   */
  public void endElement(String namespaceURI, String sName, String qName) {

    String tagName = sName;
    if ("".equals(sName) || (sName == null)) {
      tagName = qName;
    }

    if (tagName.equals("Exception")) {

      // Put the  URL Mapping into the Hashmap
      hmap.put(excpMap.getClassName(), excpMap);
    }

    lastTag = null;
  }

  /**
   * This method is notified when the characters in-between tags is encountered.
   *
   * @param ch Character array of the text
   * @param offset start position in the char array
   * @param len length of the characters to be taken from the char array
   * @since 1.0
   */
  public void characters(char[] ch, int offset, int len) {

    if (len == 0 || lastTag==null)    return;


    String tagValue = new String(ch, offset, len);

    if (lastTag.equals("Class"))

      excpMap.setClassName(tagValue);

    else if (lastTag.equals("WebErrorPage"))

      excpMap.setNextWebScreen(tagValue);

    else if (lastTag.equals("MobileErrorPage"))

      excpMap.setNextMobileScreen(tagValue);
  }

}