文檔地址: https://openhome.alipay.com/developmentDocument.htm
SDK地址：https://docs.open.alipay.com/203/105910/
Maven手動安裝支付SDK：
mvn install:install-file -Dfile=D:\Ali\alipay-sdk-java20170829142630.jar -DgroupId=com.alipay -DartifactId=sdk -Dversion=20170829142630 -Dpackaging=jar