Please explain to the beggar

Question

decided to install the java toolset on your kubuntu. and ran into a problem. download from the site java.com or from java.sun.com, the common sense speaks with java.com. because oracle is now the chief java. but there is the 8th version. And on java.sun.com the 9th. tell me who knows ..

Answer 1

better. from the official site download

Answer 2

https://tecadmin.net/install-oracle-java-8-ubuntu-via-ppa/