RTEditor/src/main/java/com/onegravity/rteditor/converter/tagsoup/HTMLWriter.java
private boolean booleanAttribute(String localName, String qName,
                                     String value) {
        String name = localName;
        if (name == null) {
            int i = qName.indexOf(':');
            if (i != -1)
                name = qName.substring(i + 1, qName.length());
        }
        if (!name.equals(value))
            return false;
        for (int j = 0; j < booleans.length; j++) {
            if (name.equals(booleans[j]))
                return true;
        }
        return false;
    }
private boolean booleanAttribute(String localName, String qName,
                                     String value) {
        String name = localName;
        if (name == null) {
            int i = qName.indexOf(':');
            if (i != -1)
                name = qName.substring(i + 1, qName.length());
        }
        if (!name.equals(value))
            return false;
        for (int j = 0; j < booleans.length; j++) {
            if (name.equals(booleans[j]))
                return true;
        }
        return false;
    }
Return true if the attribute is an HTML boolean from the above list.