问题
As dicussed about the name here, I wonder why we have the number two 2 in the name J2EE? Was there J1EE or J0EE?
回答1:
From Java Ranch
Sun went through a name change a little bit ago. The first release of Java was called simply Java.
Then the platform was updated and was called Java 2 and we got versions like: Java 2 version 1.3, 1.4... And you got the Standard Edition names looking like: J2SE 1.3, 1.4, ...The Enterprise Edition followed the same scheme: Java 2 Enterprise Edition version 1.2, 1.3... Which came out to be J2EE 1.3, ...
Because it was confusing people why Java 2 had versions 1.x for so long they renamed it in later versions to be: Java Standard Edition 5.0, 6.0, 7.0 or just Java 5 and Java 6 instead of J2SE 1.5 and J2SE 1.6.
The Enterprise Edition followed suit with JEE 5 instead of J2EE 1.5.
The difference, then is that Java Enterprise Editions < version 5 have names like J2EE 1.3 or J2EE 1.4 while Java Enterprise Editions >= 5 will have names like JEE 5, JEE 6, ...
来源：https://stackoverflow.com/questions/26359326/why-there-is-number-two-in-j2ee-name