So if you want to find files with a given extension in windows, this is how you would do:
$> where /r . *.java C:\Program Files\Java\jdk-9\my-samples\sample1\src\org.astro\module-info.java C:\Program Files\Java\jdk-9\my-samples\sample1\src\org.astro\org\astro\World.java
where,
- /r says recursively search and match for files with given pattern,
- and the argument after /r says to start from current directory
If you want to get more information use where/? which is the way to reach the help for the command