Yes IDEs save time, but they add imports automatically, provide you suggestions on class names, create a basic structure of classes (like
servlet or filter) automatically from templates. Because of this a person might not remember the exact syntax of doGet method or the class to extend in a filter or the structure of web.xml. When I learned JavaEE, I used Netbeans IDE but what I used to do is create a normal class (instead of using Servlet or Filter templates) so that I would have to extend the servlet class myself and declare the doGet/doPost method(s) myself. This helped me in memorizing the method signatures and saved me from having to manually package the war file and deploying it...