Core Servlets and JavaServer Pages™

A.10. JSP Scripting Elements

Types of Scripting Elements

• Expressions: <%= expression %>

  Evaluated and inserted into servlet's output. You can also use

  <jsp:expression>
  expression
  </jsp:expression>
  

• Scriptlets: <% code %>

  Inserted into servlet's _jspService method (called by service). You can also use

  <jsp:scriptlet>
  code
  </jsp:scriptlet>
  

• Declarations: <%! code %>

  Inserted into body of servlet class, outside of any existing methods. You can also use

  <jsp:declaration>
  code
  </jsp:declaration>
  

Template Text

• Use <\% to get <% in output.

• <%-- JSP Comment --%>

• <!-- HTML Comment -->

• All other non-JSP-specific text passed through to output page.

Predefined Variables

Implicit objects automatically available in expressions and scriptlets (not declarations).