Exemplo n.º 1
0
  /**
   * Parse an HTML file.
   *
   * @param buffer - buffer containing HTML file text
   * @return true if file is valid HTML, false otherwise
   */
  public boolean validate(StringBuffer buffer) {
    ITag root = new RootTag();

    try {
      ParseHtml(buffer, root);
    } catch (HtmlParseException e) {
      /*
       * Debugging output off. System.out.println(e.getMessage());
       * e.printStackTrace();
       */
      return false;
    }

    ValidationVisitor visitor = new ValidationVisitor();
    root.Accept(visitor);
    System.out.println("Validation result: " + visitor.IsValid());
    return visitor.IsValid();
  }
Exemplo n.º 2
0
 /**
  * Add a text object to the tree (leaf). May either be pure whitespace or may contain characters.
  */
 private void AddTextElement(String str, ITag tag) {
   try {
     if (!str.isEmpty()) {
       tag.Add(textFactory.Create(str));
     }
   } catch (NotImplementedException e) {
     e.printStackTrace();
   }
 }
Exemplo n.º 3
0
  /**
   * Build the HTML composite tree.
   *
   * @param buffer - File text from which to build the tree.
   * @param root - Root node of the tree.
   * @throws HtmlParseException
   */
  private void ParseHtml(StringBuffer buffer, ITag root) throws HtmlParseException {
    int startIndex = 0;

    // Iterate as long as there are children
    while (true) {
      int startTagStartIndex = 0;
      int startTagEndIndex = 0;
      int endTagStartIndex = 0;
      int endTagEndIndex = 0;

      // Find the beginning of the next start tag ------------------------
      startTagStartIndex = buffer.indexOf(START_TAG_START, startIndex);

      // This is the base case.
      if (startTagStartIndex < 0) {
        AddTextElement(buffer.substring(startIndex), root);
        return;
      }

      // Find the end of the next start tag ------------------------------
      startTagEndIndex = buffer.indexOf(TAG_END, startTagStartIndex);
      if (startTagEndIndex < 0) {
        throw new HtmlParseException("No '>' found for opening tag.");
      }

      String startTag = buffer.substring(startTagStartIndex + 1, startTagEndIndex);
      String tagname = startTag.replaceAll("\\s+$", "");

      // Find the beginning of the corresponding end tag -----------------
      endTagStartIndex = buffer.indexOf(END_TAG_START + startTag.trim(), startTagEndIndex);
      if (endTagStartIndex < 0) {
        throw new HtmlParseException("No '</' found for closing tag.");
      }

      // Find the corresponding end tag ----------------------------------
      endTagEndIndex = buffer.indexOf(TAG_END, endTagStartIndex);
      if (endTagEndIndex < 0) {
        throw new HtmlParseException("No '>' found for closing tag.");
      }

      String endTag = buffer.substring(endTagStartIndex + 1, endTagEndIndex);

      // See if there is a string before this tag.
      if (startIndex != startTagStartIndex) {
        String str = buffer.substring(startIndex, startTagStartIndex);
        AddTextElement(str, root);
      }

      // Create the tag
      ITag tag = (ITag) factory.Create(startTag, endTag);
      if (tag == null) {
        throw new HtmlParseException("Invalid HTML tag: '" + tagname + "'");
      }

      try {
        root.Add(tag);
      } catch (NotImplementedException e) {
        e.printStackTrace();
      }

      // Make the recursive parsing call to parse below the tag
      String tagstring = buffer.substring(startTagEndIndex + 1, endTagStartIndex);
      StringBuffer subbuffer = new StringBuffer(tagstring);
      ParseHtml(subbuffer, tag);

      // Set up the starting index for the iteration
      startIndex = endTagEndIndex + 1;
    }
  }