// HTML Escape Macro Code for jEdit (2011-09-22)

void escapeHTML() {
    text = textArea.getSelectedText();
    if(text != null){
        text = text.replaceAll("&"  , "&");
        text = text.replaceAll("<"  , "&lt;");
        text = text.replaceAll(">"  , "&gt;");
        text = text.replaceAll("\""  , "&quot;");
        text = text.replaceAll("'"  , "&#39;");
        textArea.setSelectedText(text);
    }
}

if (buffer.isReadOnly()) {
    Macros.error(view, "Buffer is read-only.");
} else {
    escapeHTML();
}