/**
   * This method is called AFTER the content has been inserted into the document and the element
   * structure has been updated.
   *
   * <p>The syntax-highlighting updates need to be done here (as opposed to an override of <code>
   * postRemoveUpdate</code>) as this method is called in response to undo/redo events, whereas
   * <code>postRemoveUpdate</code> is not.
   *
   * <p>Now that the text is actually inserted into the content and element structure, we can update
   * our token elements and "last tokens on lines" structure.
   *
   * @param chng The change that occurred.
   * @see #removeUpdate
   */
  protected void fireRemoveUpdate(DocumentEvent chng) {

    Element lineMap = getDefaultRootElement();
    int numLines = lineMap.getElementCount();

    DocumentEvent.ElementChange change = chng.getChange(lineMap);
    Element[] removed = change == null ? null : change.getChildrenRemoved();

    // If entire lines were removed...
    if (removed != null && removed.length > 0) {

      int line = change.getIndex(); // First line entirely removed.
      int previousLine = line - 1; // Line before that.
      int previousTokenType =
          (previousLine > -1 ? lastTokensOnLines.get(previousLine) : Token.NULL);

      Element[] added = change.getChildrenAdded();
      int numAdded = added == null ? 0 : added.length;

      // Remove the cached last-token values for the removed lines.
      int endBefore = line + removed.length - numAdded;
      // System.err.println("... removing lines: " + line + " - " + (endBefore-1));
      // System.err.println("... added: " + numAdded + ", removed: " + removed.length);

      lastTokensOnLines.removeRange(
          line, endBefore); // Removing values for lines [line-(endBefore-1)].
      // System.err.println("--------- lastTokensOnLines.size() == " + lastTokensOnLines.getSize());

      // Update last tokens for lines below until they've stopped changing.
      updateLastTokensBelow(line, numLines, previousTokenType);

    } // End of if (removed!=null && removed.size()>0).

    // Otherwise, text was removed from just one line...
    else {

      int line = lineMap.getElementIndex(chng.getOffset());
      if (line >= lastTokensOnLines.getSize())
        return; // If we're editing the last line in a document...

      int previousLine = line - 1;
      int previousTokenType =
          (previousLine > -1 ? lastTokensOnLines.get(previousLine) : Token.NULL);
      // System.err.println("previousTokenType for line : " + previousLine + " is " +
      // previousTokenType);
      // Update last tokens for lines below until they've stopped changing.
      updateLastTokensBelow(line, numLines, previousTokenType);
    }

    // Let all of our listeners know about the removal.
    super.fireRemoveUpdate(chng);
  }
 @Override
 protected void fireRemoveUpdate(DocumentEvent e) {
   parse();
   super.fireRemoveUpdate(e);
 }