Reference variable : Variable « JSP « Java Tutorial

  Copyright (c) 2002 by Phil Hanna
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<%@ page session="false" %>
   int value = 3;
<P>The value is <%= value %></p>
   value += 2;
<P>After adding 2, the value is <%= value %></p>

23.2.1.Creating a Variable
23.2.2.Define variable and reference it later
23.2.3.Reference variable
23.2.4.Page counter