You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@tomcat.apache.org by cr...@apache.org on 2001/07/24 02:26:55 UTC
cvs commit: jakarta-tomcat-4.0/webapps/examples/WEB-INF/classes/filters SetCharacterEncodingFilter.java
craigmcc 01/07/23 17:26:55
Modified: webapps/examples/WEB-INF web.xml
Added: webapps/examples/WEB-INF/classes/filters
SetCharacterEncodingFilter.java
Log:
Add an example filter that unconditionally sets the character encoding
(used to interpret request parameters when request.getParameter() and
friends are called) to a configurable value. It is very easy to subclass
this filter to make it smarter about what encoding to select. Examples of
things you might want to look at in selectEncoding() include:
* Any value(s) specified for the "Accept-Language" header, if you
can make assumptions about what encoding to use for specific locales.
* Any value specified for the "User-Agent" header, if you can make
assumptions based on the client browser.
* Any values you have stashed in a session associated with this request.
Revision Changes Path
1.16 +20 -0 jakarta-tomcat-4.0/webapps/examples/WEB-INF/web.xml
Index: web.xml
===================================================================
RCS file: /home/cvs/jakarta-tomcat-4.0/webapps/examples/WEB-INF/web.xml,v
retrieving revision 1.15
retrieving revision 1.16
diff -u -r1.15 -r1.16
--- web.xml 2001/04/05 19:30:40 1.15
+++ web.xml 2001/07/24 00:26:55 1.16
@@ -28,7 +28,17 @@
<filter-class>filters.RequestDumperFilter</filter-class>
</filter>
+ <!-- Example filter to set character encoding on each request -->
<filter>
+ <filter-name>Set Character Encoding</filter-name>
+ <filter-class>filters.SetCharacterEncodingFilter</filter-class>
+ <init-param>
+ <param-name>encoding</param-name>
+ <param-value>EUC_JP</param-value>
+ </init-param>
+ </filter>
+
+ <filter>
<filter-name>Compression Filter</filter-name>
<filter-class>compressionFilters.CompressionFilter</filter-class>
@@ -51,6 +61,16 @@
<filter-name>Path Mapped Filter</filter-name>
<url-pattern>/servlet/*</url-pattern>
</filter-mapping>
+
+
+<!-- Example filter mapping to apply the "Set Character Encoding" filter
+ to *all* requests processed by this web application -->
+<!--
+ <filter-mapping>
+ <filter-name>Set Character Encoding</filter-name>
+ <url-pattern>/*</url-pattern>
+ </filter-mapping>
+-->
<!--
<filter-mapping>
1.1 jakarta-tomcat-4.0/webapps/examples/WEB-INF/classes/filters/SetCharacterEncodingFilter.java
Index: SetCharacterEncodingFilter.java
===================================================================
/*
* $Header: /home/cvs/jakarta-tomcat-4.0/webapps/examples/WEB-INF/classes/filters/SetCharacterEncodingFilter.java,v 1.1 2001/07/24 00:26:55 craigmcc Exp $
* $Revision: 1.1 $
* $Date: 2001/07/24 00:26:55 $
*
* ====================================================================
*
* The Apache Software License, Version 1.1
*
* Copyright (c) 1999-2001 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution, if
* any, must include the following acknowlegement:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowlegement may appear in the software itself,
* if and wherever such third-party acknowlegements normally appear.
*
* 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
* Foundation" must not be used to endorse or promote products derived
* from this software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache"
* nor may "Apache" appear in their names without prior written
* permission of the Apache Group.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
* [Additional notices, if required by prior licensing conditions]
*
*/
package filters;
import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.UnavailableException;
/**
* Example filter that unconditionally sets the character encoding to be used
* in parsing the incoming request to a value specified by the
* <strong>encoding</string> filter initialization parameter in the web app
* deployment descriptor (</code>/WEB-INF/web.xml</code>). This filter could
* easily be extended to be more intelligent about what character encoding to
* set, based on characteristics of the incoming request (such as the values
* of the <code>Accept-Language</code> and <code>User-Agent</code> headers,
* or a value stashed in the current user's session).
*
* @author Craig McClanahan
* @version $Revision: 1.1 $ $Date: 2001/07/24 00:26:55 $
*/
public class SetCharacterEncodingFilter implements Filter {
// ----------------------------------------------------- Instance Variables
/**
* The default character encoding to set for requests that pass through
* this filter.
*/
protected String encoding = null;
/**
* The filter configuration object we are associated with. If this value
* is null, this filter instance is not currently configured.
*/
protected FilterConfig filterConfig = null;
// --------------------------------------------------------- Public Methods
/**
* Take this filter out of service.
*/
public void destroy() {
this.encoding = null;
this.filterConfig = null;
}
/**
* Select and set (if specified) the character encoding to be used to
* interpret request parameters for this request.
*
* @param request The servlet request we are processing
* @param result The servlet response we are creating
* @param chain The filter chain we are processing
*
* @exception IOException if an input/output error occurs
* @exception ServletException if a servlet error occurs
*/
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain)
throws IOException, ServletException {
// Select and set (if needed) the character encoding to be used
String encoding = selectEncoding(request);
if (encoding != null)
request.setCharacterEncoding(encoding);
// Pass control on to the next filter
chain.doFilter(request, response);
}
/**
* Place this filter into service.
*
* @param filterConfig The filter configuration object
*/
public void init(FilterConfig filterConfig) throws ServletException {
this.filterConfig = filterConfig;
this.encoding = filterConfig.getInitParameter("encoding");
}
// ------------------------------------------------------ Protected Methods
/**
* Select an appropriate character encoding to be used, based on the
* characteristics of the current request and/or filter initialization
* parameters. If no character encoding should be set, return
* <code>null</code>.
* <p>
* The default implementation unconditionally returns the value configured
* by the <strong>encoding</strong> initialization parameter for this
* filter.
*
* @param request The servlet request we are processing
*/
protected String selectEncoding(ServletRequest request) {
return (this.encoding);
}
}