public static TextRange getPrefixRange(XmlAttribute attribute) {
    final String value = attribute.getValue();
    final int p = value.indexOf(':');
    if (p == -1) {
      return TextRange.from(0, 0);
    } else {
      for (int i = p - 1; i >= 0 ; i--) {
        if (!Character.isJavaIdentifierPart(value.charAt(i))) {
          return TextRange.create(i + 1, p);
        }
      }
      return TextRange.from(0, p);
    }
  }
public static TextRange getPrefixRange(XmlAttribute attribute)