Jsp Syntax Examples

JSP Syntax card with examples Element

JSP Style

Comment

<%--

Declaration

<%! int x=0; boolean bBool = false; %>

Expression

<%= bool %> Any java primitive or string etc.

Scriptlet

Text

<% java code fragment; %> Nil

Include Directive

<%@ include file=”myPage.jsp” %>

Page Directive

<%@ page language=’java’ | import=’com.neon.pack.*’ | session=’true’ | ‘false’ buffer=’none’ | ‘8kb’ autoflush=’true’ | ‘false’ isThreadSafe=’true’ | ‘false’ info=’blah’ errorpage=’errro_blah.jsp’ isErrorPage=’true’ | ‘false’ %> <%@ taglib uri=’/tagdir/myTag.tld’ prefix=’me’ %>

bold = default

Taglib Directive

Tag usage

<jsp:forward>

<jsp:getProperty> <jsp:include>

comment here

XML Style ---%>

<me:tester year=’2003’ /> <me:tagger age=’38’ > jsp body -- -- - <jsp:forward page=’myPage.jsp’ /> <jsp:forward page=’<%= expression %>’ /> <jsp:forward page=’myPage.jsp’ > <jsp:param name=’age’ value=’39’ /> <jsp:param name=’age’ value= ‘<%= expression %>’ /> <jsp:getProperty name=’addressBean’ property=’zip’ /> <jsp:include page=’myPage.jsp’ flush=’true|false’ /> <jsp:include page=’<%= expression %>’ flush=’true|false’ />

Nil <jsp:declaration> int x=0; boolean bBool =false; <jsp:expression> bool <jsp:scriptlet> java code fragment; <jsp:text> free flowing text <jsp:directive.include file=” myPage.jsp” /> <jsp:directive.page language=’java’ | import=’ ’com.neon.pack.*’ | session=’true’ | ‘false’ buffer=’none’ | ‘8kb’ autoflush=’true’ | ‘false’ isThreadSafe=’true’ | ‘false’ info=’blah’ errorpage=’errro_blah.jsp’ isErrorPage=’true’ | ‘false’ /> <jsp:root xmlns:jsp=’http://java.sun.com/jsp/page’ à xmlns:me=’/taglib/myTag.tld > -- -- --- -- - -- same as jsp --

<jsp:forward page=’myPage.jsp’ /> <jsp:forward page=’%= expression %>’ /> <jsp:forward page=’myPage.jsp’ > <jsp:param name=’age’ value=’39’ /> <jsp:param name=’age’ value= ‘<%= expression %>’ /> <jsp:getProperty name=’addressBean’ property=’zip’ /> -- same --<jsp:include page=’%= expression %’ flush=’true|false’ /> -- same ---

<jsp:include page=’myPage.jsp’ > <jsp:param name=’street’ value=’Goddard’>



<jsp:useBean>

<jsp:include page=’myPage.jsp’ > <jsp:param name=’street’ value= ‘<%= expression %>’ />

<jsp:include page=’myPage.jsp’ > <jsp:param name=’street’ value= ‘%= expression %’ />

<jsp:useBean id=’objAddress’ scope=’page’

-- same --

class=’com.neon.OfficeAddressBean’ type=’com.neon.AddressBean’ />

<jsp:setProperty>

<jsp:useBean beanName=’addressBean type=’com.neon.Address’ ’ / > <jsp:useBean beanName=’<%= exprr >’ type=’com.neon.Address’ ’ / > <jsp:setProperty name=’objBeanName’ property=’*’> <jsp:setProperty name=’objBeanName’ property=’city’ param=’myCity’ />

<jsp:setProperty name=’objBeanName’ property=’city’ value=’Bracknell’ />

jsp:plugin

<jsp:setProperty name=’objBeanName’ property=’city’ value=’<%=expr%>’ /> <jsp:plugin Compulsory elements type=’bean | applet’ code=’class file name’ codebase=’class file dir name’ Optional elements name archive align height width hspace jreversion nspluginurl iepluginurl > <jsp:params> <jsp:param name=’namer’ value=’val’> <jsp:fallback> message

An area of confusion is when to use the include directive instead of the include action and vice versa. Include Directive <%@ include file= ‘myPage.jsp’ %> Translation time Fast File changes rarely

Actual file is included The 2 pages might not compile independently The variables can be shared

Produced by Yogen Joshi for VisualBuilder.com

Include Action <jsp:include page=’myPage.jsp’ /> Request time Slow File changes quite often Response of the included file is included The 2 files can [should] compile independently Variables between the 2 pages can be shared only through Different scopes e.g. context, session, request,etc.