pre_upgrade() {
    # Keep existing '-javaagent' options, if any
    if [ -e "/opt/sts4/SpringToolSuite4.ini" ]; then
        grep "^\-javaagent" /opt/sts4/SpringToolSuite4.ini > /tmp/sts4.javaagents || return 0
    fi
}

post_install() {
    gtk-update-icon-cache -q -t -f usr/share/icons/hicolor
}

post_upgrade() {
    post_install $1

    # Restore existing '-javaagent' options, if any
    if [ -s "/tmp/sts4.javaagents" ]; then
        cat /tmp/sts4.javaagents >> /opt/sts4/SpringToolSuite4.ini
    fi
    rm -f /tmp/sts4.javaagents
}

post_remove() {
    gtk-update-icon-cache -q -t -f usr/share/icons/hicolor
}