JSP Note 1

4. jsp will eventually be converted to servlet for execution.
5. jsp declaration format: <%! Int A = 3 ;%>, script segment format: <% int B = 3 ;%>, when the server converts JSP to servlet, will convert the Declaration in JSP to the class
Member variable, and the script segment is converted into a local variable in the method. servlet is a single instance, so that the value of the member variable is only one, and each user will access it, the value in the script segment is a local variable. each user has a copy of each variable during access, which does not affect each other.
6. jsp inclusion (include)
7. <JSP: Forward> command is used to redirect to the page. AllCodeThere is no chance to execute it, because the page process has switched to another page.

8. The getparameter method is a special case of the getparametervalues method, indicating the Request Parameter

There is only one value. If there are multiple request parameter values, use the getparametervalues method. In case of multiple check boxes, you must use the getparametervalues method to obtain the values of multiple check boxes selected by the user.