I found a solution,thanks to this topic Change Docker for Mac Engine /etc files - #2 by iconara , the only thing I needed to do to access the docker host was use this command:
screen ~/Library/Containers/com.docker.docker/Data/com.docker.driver.amd64-linux/tty
username：root
password：[empty]
close session：Ctrl+a d
To change the swap size for oracle xe installation:
dd if=/dev/zero of=/var/swap.file count=2000000 bs=1024
chmod go= /var/swap.file
mkswap /var/swap.file
echo “/var/swap.file swap swap defaults 0 0” >> /etc/fstab