git 如何指定某个文件暂时不提交？

git stash

你可以 add .
然后 reset xml

或者

https://github.com/ndbroadbent/scm_breeze

git update-index

--[no-]assume-unchanged
When this flag is specified, the object names recorded for the paths
are not updated. Instead, this option sets/unsets the "assume
unchanged" bit for the paths. When the "assume unchanged" bit is on,
the user promises not to change the file and allows Git to assume that
the working tree file matches what is recorded in the index. If you
want to change the working tree file, you need to unset the bit to
tell Git. This is sometimes helpful when working with a big project on
a filesystem that has very slow lstat(2) system call (e.g. cifs).

Git will fail (gracefully) in case it needs to modify this file in the
index e.g. when merging in a commit; thus, in case the
assumed-untracked file is changed upstream, you will need to handle
the situation manually.

暂存 然后提交了再取出？

git status|grep modified|grep java$|awk '{print $NF}'|xargs git add

Interactive Staging
https://git-scm.com/book/en/v2/Git-Tools-Interactive-Staging

用 GUI 吧，比如 SourceTree ，直观省事

git add *.java ?

可以临时 checkout 到一个新的分支 commit ，完了再回来，在 reset 。

git add **/*.java
或者
git add .
git reset --- path-to-xml
不加 hard git 不会动工作目录

git stash 正解，推荐 sourcetree