原文： https://www.jianshu.com/p/fe6b68295479
jdk 1.8 下载地址 https://www.oracle.com/java/technologies/javase/javase-jdk8-downloads.html
jdk的配置 https://www.jianshu.com/p/a85658902f26
maven的安装和配置 https://www.cnblogs.com/chenyanbin/p/12506889.html