1. 下载apktool http://code.google.com/p/android-apktool/
java -jar apktool_2.0.0rc3.jar d aaaaaaaaaaaaa.apk
2. 下载dex2jar http://code.google.com/p/dex2jar/
chmod +x d2j-dex2jar.sh
./d2j-dex2jar.sh ../aaaaaaaaaaaaa.apk
3. jar已经出来了，扔到带jadclipse的eclipse中或者找个jd-gui查看
原文：http://www.cnblogs.com/hanhongmin/p/4143575.html