Zhang Wuji when I learn Tai Chi, Chi Master admonished his father's master must take him before the learned martial arts all forget, forget the more you will learn faster.
Similarly, when the self-learning Java Java must first know what knowledge do not need to learn, after all, iterative update technology as fast as if rockets, some Java knowledge already past the point of. If you do not know how to break Sheli, it can not help but learn it too painful.
1) AWT and Swing
I really do not know why, some books also introduce AWT and Swing, which does not seem to know that the great Qing Dynasty already dead for hundreds of years the same. 9102 has been, and who will use AWT and Swing to develop desktop applications do?
As far as I know, C ++ programmers use MFC, C # programmers will use Winform and WPF. You can even use a more fashionable technologies (such as Electron) to Web pages wrapped in a layer of gorgeous coat, turned into an executable file.
2）Applet
As a web plug-in technology, Applet never even caught on, and even the once popular Flash should be eliminated.
3）XML
XML has not been eliminated, there are many local applications. However, as a data transmission format, it is to be replaced JSON.
4）JDBC
Personally, I do not propose to study bias underlying JDBC, especially for self-learning programmers valuable time. Instead of spending this time, it is better to MyBatis energy into learning.
5）Struts
Struts is an excellent early MVC framework, from a technical point of view, is still pretty good. But since been SpringMVC, Struts was shot dead on the beach.
6）Hibernate
In the (sometime in 2010) I just had a job that would be, what with the Hibernate persistence framework. But things have changed, Hibernate too heavyweight, learning cost is too high, replaced by lightweight MyBatis (support for custom SQL, stored procedures and advanced mapping).
7）JSP
Speaking ashamed, a project I maintain the view layer remains JSP. But now popular is the "before and after the end of the separation", JSP becomes outdated.