Types of Scripting Elements

Expressions

Format: 

<%= expression %>

Evaluated and inserted into the servlet's output. I.e., 

results in something like out.println(expression)

Scriptlets

Format: 

<% code %>

Inserted verbatim into the servlet's _jspService method 

(called by service)

Declarations

Format: 

<%! code %>

Inserted verbatim into the body of the servlet class, 

outside of any existing methods

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JSP Expressions

Format

<%=

Java Expression 

%>

Result

Expression evaluated, converted to String, and placed 

into HTML page at the place it occurred in JSP page

That is, expression placed in _jspService inside out.print

Examples

Current time: <%= new java.util.Date() %>

Your hostname: <%= request.getRemoteHost() %>

XML compatible syntax

Java Expression

XML version not supported by Tomcat 3. Until JSP 1.2, 

servers are not required to support it.

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