代码提交（Repo、Git）

1.修改代码
2.git start –all branch_name
2.git add xxx/xxx.java xxx/xxx/xxx.java
3.git commit (Or git commit –amend)
4.repo upload

repo init
repo sync -c
repo branch
repo checkout branch_name
repo abandon branch_name
git status
git log (Or gitk)
git clean -df
git reset –hard HEAD