Including Files and
Applets in JSP Pages
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Table of content
The
jsp:include action
Using jsp:include to include pages at request time.
The
include directive
To include files at page translation time.
The
jsp:plugin action
To include applets for the Java Plug-in.
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Including Pages at RequestTime:
jsp:include
Format
Purpose
To
reuse JSP, HTML, or plain text content
To
permit updates to the included content without
changing the main JSP page(s)
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Including Pages at RequestTime:
jsp:include
• Function
A portable mechanism that lets you insert
any of the following into the JSP output:
The content of an
HTML page
The content of a plain
text document
The ouput of JSP page
The output of a servlet
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Including Pages at RequestTime:
jsp:include
The page Attribute:
URLs that do not start with a slash are interpreted relative to
the location of the main page( main directory).
URLs that start with a slash are interpreted relative to the base
Web application directory, not relative to the server root.
http://host/headlines/sports/table-tennis.jsp.
Ex:
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Including Pages at RequestTime:
jsp:include
Notes
Output
You
Url
can not contain JSP.
are permitted to include files from WEB-INF.
start with slashes
The
server always interprets them relative to the
current Web application.
The
browser always interprets them relative to the
server root.
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Including Pages at RequestTime:
jsp:include
The
flush Attribute
This
attribute is optional.
The
output stream of the main page should flushed before
the inclusion of the page
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Including Pages at RequestTime:
jsp:include
Example: A news Headline page
…
Here is a summary of our three
most recent news stories:
-
-
-
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Including Pages at RequestTime:
jsp:include
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Including Files at Page Translation Time:
<%@ include … %>
Format
<%@
include file="Relative address" %>
Purpose
To
reuse JSP content in multiple pages
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Including Files at Page Translation Time:
<%@ include … %>
Example
The include Directive
Example
The include Directive Example
<%@ include file="footer.jsp" %>
<%-- footer.jsp --% >
Copyright © 2010
Including Files at Page Translation Time:
<%@ include … %>
Differences between jsp:include and include directive
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Including Files at Page Translation Time:
<%@ include … %>
Example:
Reusing Footers
SomeRandomPage.jsp
ContactSection.jsp
……
bla, bla bla
<%@ include
file="/WEBINF/ContactSection.jsp" %>
<%!
private int accessCount = 0;
private Date accessDate = new Date();
%>
……
This page has been accessed <%=
++accessCount %>
at <%= accessDate %>.
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Including Files at Page Translation Time:
<%@ include … %>
Example: Reusing Footers
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Applets and jsp:plugin
What
is applets
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Applets and jsp:plugin
What is applets
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Applets and jsp:plugin
Why Applets?
When UI requirements demand it
Major drawbacks
Alternatives
Options for Deploying Applets
Develop the applets with JDK 1.1 or even 1.02
Have users install any version of the Java 2 Plug-in, then use Java 2
for the applets
Have users install version 5 or 6 of the Java Runtime Environment
(JRE), then use JDK 1.5/1.6 for the applets
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Applets and jsp:plugin
Using jsp:plugin
APPLET Tag
Equivalent jsp:plugin
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Applets and jsp:plugin
WindowUtilities.java
Example
PluginApplet.jsp
public static void
setNativeLookAndFeel()
PluginApplet.java
public void init()
TextPanel.java
DrawingPanel drawingPanel;
public TextPanel()
DrawingPanel.java
public void
paintComponent(Graphics g)
public void setFontName(String
fontName)
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Applets and jsp:plugin
Example
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