/*
============================================================================
The Apache Software License, Version 1.1
============================================================================
Copyright (C) 1999-2003 The Apache Software Foundation. All rights reserved.
Redistribution and use in source and binary forms, with or without modifica-
tion, 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 acknowledgment: "This product includes software
developed by the Apache Software Foundation (http://www.apache.org/)."
Alternately, this acknowledgment may appear in the software itself, if
and wherever such third-party acknowledgments normally appear.
4. The names "Apache Cocoon" 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 name, without prior written permission of the
Apache Software Foundation.
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 (INCLU-
DING, 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 and was originally created by
Stefano Mazzocchi <stefano@apache.org>. For more information on the Apache
Software Foundation, please see <http://www.apache.org/>.
*/
package org.apache.cocoon.selection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import org.apache.avalon.framework.configuration.Configurable;
import org.apache.avalon.framework.configuration.Configuration;
import org.apache.avalon.framework.configuration.ConfigurationException;
import org.apache.avalon.framework.parameters.Parameters;
import org.apache.commons.collections.SequencedHashMap;
import org.apache.commons.jxpath.CompiledExpression;
import org.apache.commons.jxpath.JXPathContext;
/**
* Additional to the inherited functionality from its superclass ExceptionSelector,
* this selector allows to define xpath expressions to evaluate supplemental information
* given in the thrown exception.
* The configuration of this selector allows to map not only exceptions but also
* xpath expressions to symbolic names that are used in the <map:when> alternatives.
* <p>
* Example configuration :
* <pre>
* <map:selector type="error" src="....XPathExceptionSelector">
* <exception name="denied" class="my.comp.auth.AuthenticationFailure">
* <xpath name="PasswordWrong" test="authCode=10"/>
* <xpath name="PasswordExpired" test="errorCode=11"/>
* <xpath name="AccessForbidden" test="errorCode>11"/>
* </exception>
* </map:selector>
* </pre>
* This example shows several features :
* <li>the test is the xpath expression that will be evaluated against the exception ,</li>
* <li>an xpath expression can be given a name, which is used in the <map:when> tests,</li>
*
* @author <a href="mailto:juergen.seitz@basf-it-services.com">Jürgen Seitz</a>
* @author <a href="mailto:bluetkemeier@s-und-n.de">Björn Lütkemeier</a>
* @since 2.1
* @version CVS $Id: XPathExceptionSelector.java,v 1.6 2003/08/12 06:01:40 cziegeler Exp $
*/
public class XPathExceptionSelector extends ExceptionSelector
implements Configurable {
private Map exception2XPath = new HashMap();
public void configure(Configuration conf) throws ConfigurationException {
super.configure(conf);
Configuration[] children = conf.getChildren("exception");
Configuration[] xPathChildren;
for (int i = 0; i < children.length; i++) {
// Check if there are XPath-Expressions configured
xPathChildren = children[i].getChildren("xpath");
Map xPathMap = new SequencedHashMap(11);
for (int j = 0; j < xPathChildren.length; j++) {
Configuration xPathChild = xPathChildren[j];
String xPathName = xPathChild.getAttribute("name");
CompiledExpression xPath = JXPathContext.compile(xPathChild.getAttribute("test"));
xPathMap.put(xPathName, xPath);
}
if (xPathMap.size() > 0) {
// store xpath - config if there is some
exception2XPath.put(children[i].getAttribute("name", null),
xPathMap);
}
}
}
/**
* Compute the exception type, given the configuration and the exception stored in the object model.
*/
public Object getSelectorContext(Map objectModel, Parameters parameters) {
// get exception from super class
FindResult selectorContext = (FindResult) super.getSelectorContext(objectModel,
parameters);
if (selectorContext != null) {
String exceptionName = selectorContext.getName();
Throwable t = selectorContext.getThrowable();
Map xPathMap = (Map) exception2XPath.get(exceptionName);
if (xPathMap != null) {
// create a context for the thrown exception
JXPathContext context = JXPathContext.newContext(t);
for (Iterator iterator = xPathMap.entrySet().iterator(); iterator.hasNext(); ) {
Map.Entry entry = (Map.Entry) iterator.next();
if (((CompiledExpression) entry.getValue()).getValue(context).equals(Boolean.TRUE)) {
// set the configured name if the expression is succesfull
selectorContext.setName((String) entry.getKey());
return selectorContext;
}
}
}
}
return selectorContext;
}
}