jdk存档链接：
https://www.oracle.com/java/technologies/oracle-java-archive-downloads.html

jdk8u202下载地址：
https://www.oracle.com/java/technologies/javase/javase8-archive-downloads.html

入口方法见：
https://blog.csdn.net/qq_15110681/article/details/112209686

Oracle如何对JDK收费
https://juejin.cn/post/6844903834674790413