JDK6：
http://www.oracle.com/technetwork/java/javase/downloads/java-archive-downloads-javase6-419409.html
JDK7：
http://www.oracle.com/technetwork/java/javase/downloads/java-archive-downloads-javase7-521261.html
JDK8：
http://www.oracle.com/technetwork/java/javase/downloads/java-archive-javase8-2177648.html
原文：http://www.cnblogs.com/nihaorz/p/5422921.html