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 can not contain JSP.
• You are permitted to include files from WEB-INF.
• Url 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
<%--%>
footer.jsp --% >
The include Directive Example
The include Directive Example
<%@ include file="footer.jsp" %>
Copyright © 2010
Including Files at Page Translation
Time:
• Differences between
jsp:include and include directive
<%@ include … %>
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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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• What is applets
Applets and jsp:plugin
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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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• Using jsp:plugin
• APPLET Tag
Applets and jsp:plugin
• Equivalent jsp:plugin
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Applets and jsp:plugin
WindowUtilities.java
public static void
setNativeLookAndFeel()
• Example
PluginApplet.jsp
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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