JSP scripting elements let you insert Java code into the servlet that will be generated from the current JSP page. There are three forms:
1.Expressions of the form <%= expression %> that are evaluated and inserted into the output,
2.Scriptlets of the form <% code %> that are inserted into the servlet's service method,
3.Declarations of the form <%! code %> that are inserted into the body of the servlet class, outside of any existing methods.
