ubuntu安装java，nodejs，dsa物联网平台

`sudo apt install default-jdk   sudo mkdir -p /usr/local/lib/nodejs sudo tar -xJvf node-$VERSION-$DISTRO.tar.xz -C /usr/local/lib/nodejs     #Set the environment variable ~/.profile, add below to the end  # Nodejs gedit ~/.profile export PATH=/usr/local/lib/nodejs/node-$VERSION-$DISTRO/bin:$PATH   #Refresh profile  . ~/.profile  node -v npm -v`