org.apache.cocoon.selection
Class ExceptionSelector

java.lang.Object
  org.apache.avalon.framework.logger.AbstractLogEnabled
      org.apache.cocoon.selection.AbstractSwitchSelector
          org.apache.cocoon.selection.ExceptionSelector

All Implemented Interfaces:

Component, Configurable, LogEnabled, ThreadSafe, Selector, SwitchSelector

Direct Known Subclasses:

XPathExceptionSelector

public class ExceptionSelector
extends AbstractSwitchSelector
implements Configurable

In a <map:handle-errors>, selects depending on the exception that caused the error. The configuration of this selector allows to map exception class names to symbolic names that are used in the <map:when> alternatives.

Example configuration :

   <map:selector type="error" src="....ExceptionSelector">
     <exception class="org.xml.sax.SAXException" name="sax" unroll="true"/>
     <exception name="not-found" class="org.apache.cocoon.ResourceNotFoundException"/>
     <exception class="org.apache.cocoon.ProcessingException" unroll="true"/>
     <exception name="denied" class="java.security.SecurityException"/>
     <exception name="denied" class="my.comp.auth.AuthenticationFailure"/>
   </map:selector>
 

This example shows several features :

the "class" is the class name of the exception (which can be any Throwable),

an exception can be given a name, which is used in the <map:when> tests,

an exception can be unrolled, meaning we try to get its cause and then consider this cause for the exception name

Note that both "name" and "unroll" can be specified. In that case, we first try to unroll the exception, and if none of the causes has a name, then the "name" attribute is considered.

Since:

2.1

Version:

CVS $Id: ExceptionSelector.html 1304258 2012-03-23 10:09:27Z ilgrosso $

Author:

Jürgen Seitz, Björn Lütkemeier, Sylvain Wallez

Field Summary

Fields inherited from interface org.apache.cocoon.selection.SwitchSelector

ROLE

Constructor Summary

ExceptionSelector()

Method Summary

void	configure(Configuration conf)
Object	getSelectorContext(Map objectModel, Parameters parameters) Compute the exception type, given the configuration and the exception stored in the object model.
boolean	select(String expression, Object selectorContext) Switch Selectors test patterns against a context object and signal success with the returned boolean value

Methods inherited from class org.apache.cocoon.selection.AbstractSwitchSelector

select

Methods inherited from class org.apache.avalon.framework.logger.AbstractLogEnabled

enableLogging, getLogger, setupLogger, setupLogger, setupLogger

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ExceptionSelector

public ExceptionSelector()

Method Detail

configure

public void configure(Configuration conf)
               throws ConfigurationException

Specified by:

configure in interface Configurable

Throws:

ConfigurationException

getSelectorContext

public Object getSelectorContext(Map objectModel,
                                 Parameters parameters)

Compute the exception type, given the configuration and the exception stored in the object model.

Specified by:

getSelectorContext in interface SwitchSelector

Parameters:

objectModel - The Map containing object of the calling environment which may be used to select values to test the expression.

parameters - The sitemap parameters, as specified by <parameter/> tags.

Returns:

Selector context

See Also:

ObjectModelHelper.getThrowable(java.util.Map)

select

public boolean select(String expression,
                      Object selectorContext)

Description copied from interface: SwitchSelector

Switch Selectors test patterns against a context object and signal success with the returned boolean value

Specified by:

select in interface SwitchSelector

Parameters:

expression - The expression to test.

selectorContext - The context this test should be performed in.

Returns:

true if the test was successful.