Sets the JSP script language to lang. Defaults to Java.
All JSP 1.0 implementations must support Java. Some implementations,
like Resin, may support other scripting languages, e.g. JavaScript.
Adds to the Java package import list for the generated Java file.
Only relevant when using Java.
Defines a page to display if an error occurs in the JSP page.
Robust applications can return informative error pages when
something goes wrong in a file, for example if a database is overloaded.
path is returned as the response file. The error page
can use the additional implicit variable exception containing the thrown exception.
path is relative to the current page. Its root is relative
to the application root.
The error page itself can be a JSP page. If the error page is a
JSP page, it can use the implicit variable exception to get
information about the thrown exception.
Gives an error page access to the exception implicit variable.
Default to false.
<%@ page isErrorPage="true" %>
<h1>Received error <%= exception.message %></h1>
Includes the raw file path at translation time.
The include directive is a replacement for an SSI include (or the C
'#include'). It includes the contents of the file at path into
the JSP file. The included file is parsed as JSP, so it can have
active elements like expressions, declarations and scriptlets.
path is relative to the current page, and its root is the
application root.
<html><head>
<title><%= title %></title>
</head>
<body color=white>
<% var title = "Hello, World"; %>
<%@ include file='header.jsp' %>
<h1><%= title %></h1>
Gives the size of the page buffer in kb or none for
no buffer. Default 8kb. If buffer is none, all
output is immediately flushed.
JSP 1.0 gives page writers flexibility by buffering its output
before sending the response to HTTP. The buffering allows error recovery and forwarding, even after
generating some content. Once the buffer has filled, it will be
flushed. So applications must still detect their errors early.
The following example generates an XML section (for variety). If
the form's query is missing the 'name' parameter, it will redirect the
results.
<?xml version='1.0'?>
<form>
<%
if (request.form["name"] == null)
pageContext.forward("redo-form.jsp");
for (var name in request.form) {
out.print("<" + name + ">");
out.print(request.form[name]);
out.println("</" + name + ">");
}
%>
</form>
Tells JSP to flush the page buffer when it fills.
Default is true.
If autoFlush is false, the JSP engine will throw an exception if
the buffer overflows.
Tells JSP that the page participates in a session. Defaults to true.
The session declaration makes the session implicit variable
available to a JSP page.
If the page doesn't use sessions, it should set session to false.
<%@ page session="true" %>
<%
session.value.count++;
%>
<h1>Welcome, visitor <%= count %></h1;>
Tells the JSP that multiple pages can execute in parallel.
Defaults to true.
JSP pages are always responsible for synchronization of shared
variables, such as the session and application
variables. In some rare cases, a page may use servlet variables
(created with a declaration), and be too lazy to handle the
synchronization.
Even with isThreadSafe=false, the JSP engine may create
multiple instances of the JSP servlet. So the page author can never
absolve herself of synchronization issues.
In the following example, a JSP engine might create 3 servlet
instances of the page. So three calls to the same page may return
counts of 17, 3 and 398. In addition, the JSP engine is free to
destroy and recreate the servlet at any time, essentially resetting
the counter to 0.
<%@ page isThreadSafe="false" %>
<%! var count = 0; %>
<h1>Welcome, visitor <%= count++ %>
Gives a brief description for the page.
Sets the content type and character encoding of the page.
contentType can also set the character encoding, for
example to utf-8.
<%@ page contentType="text/plain; charset=utf-8" %>
<%! var count = 0; %>
<h1>Welcome, visitor <%= count++ %>
Changes the generated servlet's class.
In general, a filter is a better solution than using the
extends directive.
Configures tags with prefix x to use the tag
library foo.
<%@ taglib prefix='x' uri='http://www.caucho.com/mytag/test' %>
<x:mytag/>
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