tar (child): xz: Cannot exec: No such file or directory

tarでエラーが出たため調査

$ tar -Jxvf hoge.tar.xz

これで以下のようなエラー

tar (child): xz: Cannot exec: No such file or directory
tar (child): Error is not recoverable: exiting now
tar: Child returned status 2
tar: Error is not recoverable: exiting now

ググってみると簡単に見つかった
linux - Cannot decompress .tar.xz file, getting "xz: Cannot exec: No such file or directory" from tar - Super User

xzというコマンドがないらしい
これでOK

$ sudo apt-get install xz-utils