Declaration is used to declare variables and methods in a JSP page’s scripting language. All variables and methods in JSP declaration would be translated into declaration inside respective Servlet class.
JSP declaration syntax
<%! scripting language declaration %>
JSP declaration sample code (github)
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>ourownjava.com</title> </head> <body> <!-- jsp declaration example--> <%! public int sum(final int x, final int y){ return x + y; } %> <!-- calling method --> <% out.println("sum of 10, 10 is "+sum(10, 10));%> </body> </html>