Instead of maven jarsigner, I used eclipse ADT's android tool. Like this:
Right click on the project --> Export --> Android --> Export Android Project --> some "next" --> Create New Keystore(Or use existing one) --> fill in the blanks
Your xxx.apk is ready. Then you should zip align your xxx.apk: zipalign -v 4 xxx.apk xxxOut.apk
It is done.You should upload the xxxOut.apk to Google Play.