JSP Expressions vs. Scriplets

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What we've seen so far are a number of JSP expressions:

<%= request.getParameter("first-name") %>

which treats the contents of the tag as a Java expression. In the servlet, the expression is evaluated, converted into a string, and output to the web page in the appropriate position.

To provide more power to a JSP page, we also have JSP Scriptlets, which can contain more Java code:

<!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>Countdown JSP Page</title>
  </head>
  <body>
    
    <h1>Countdown JSP Page</h1>
    <p>Counting down...</p>
    
    <%
    for (int count = 10; count > 0; count--)
    {
      out.print( count + " ");
    }
    %>
    <h3 style="color: red">BOOM!</h3>
    
  </body>
</html>

Here is what that JSP page produces:

The page was last updated February 19, 2008