PREUN

/bin/sh

{
  [ $1 = 0 ] || exit 0
  update-alternatives --remove jaxp_parser_impl /usr/share/java/xerces-j2.jar
} >/dev/null 2>&1 || :

POSTIN

/bin/sh

update-alternatives --install /usr/share/java/jaxp_parser_impl.jar \
  jaxp_parser_impl /usr/share/java/xerces-j2.jar 40