Package names for domains which end in .do
Oracle suggests you add an underscore:
In some cases, the internet domain name may not be a valid package name. This can occur if the domain name contains a hyphen or other special character, if the package name begins with a digit or other character that is illegal to use as the beginning of a Java name, or if the package name contains a reserved Java keyword, such as "int". In this event, the suggested convention is to add an underscore. For example:
hyphenated-name.example.org org.example.hyphenated_nameexample.int int_.example123name.example.com com.example._123name
Source: https://docs.oracle.com/javase/tutorial/java/package/namingpkgs.html