install spring in ubuntu java code example

Example: install spring boot on ubuntu

wget https://repo.spring.io/release/org/springframework/boot/spring-boot-cli/2.3.3.RELEASE/spring-boot-cli-2.3.3.RELEASE-bin.tar.gz
tar -xzf spring-boot-cli-2.3.3.RELEASE-bin.tar.gz
sudo mv spring-boot-cli-2.3.3.RELEASE /opt/
sudo ln -s /opt/spring-2.3.3.RELEASE/bin/spring /usr/bin/spring
sudo ln -s /opt/spring-boot-cli-2.3.3.RELEASE/shell-completion/bash/spring /etc/bash_completion.d/spring