Check the two following links for a step-by-step process on how to create .ane files.
http://gotoandlearn.com/play.php?id=148
http://gotoandlearn.com/play.php?id=149
By downloading the videos and also .ane file that are given, you actually get what structure you have to follow. Then create a bat file save it in .ane code folder
The command then is:
"path of adt bat file located in airsdk" -package -target ane "ane file name"
"location of extension xml" -swc "location of .swc file" -platform Android-ARM -C ./build/ane/Android-ARM/ .
For example:
"C:\Program Files\Adobe\Adobe Flash Builder 4.7\eclipse\plugins\com.adobe.flash.compiler_4.7.0.349722\AIRSDK\bin\adt.bat" -package -target ane upload.ane ./build/ane/extension.xml -swc ./build/ane/*.swc -platform Android-ARM -C ./build/ane/Android-ARM/ .