http://java.sun.com/j2se/1.5.0/download.jsp
J2SE 5.0
Download Java 2 Platform Standard Edition 5.0--------------http://java.sun.com/j2se/1.4.2/download.html
J2SE 1.4.2
Download Java 2 Platform, Standard Edition, v 1.4.2 (J2SE)请问这两个版本有什么区别?