package org.apache.velocity.app.event.implement;
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
import org.apache.velocity.app.event.IncludeEventHandler;
import org.apache.velocity.context.Context;
import org.apache.velocity.runtime.RuntimeServices;
import org.apache.velocity.util.ContextAware;
import org.apache.velocity.util.RuntimeServicesAware;
import org.apache.velocity.util.StringUtils;
/**
* Simple event handler that checks to see if an included page is available.
* If not, it includes a designated replacement page instead.
*
* <P>By default, the name of the replacement page is "notfound.vm", however this
* page name can be changed by setting the Velocity property
* <code>eventhandler.include.notfound</code>, for example:
* <code>
* <PRE>
* eventhandler.include.notfound = error.vm
* </PRE>
* </code>
* </p><p>
* The name of the missing resource is put into the Velocity context, under the
* key "missingResource", so that the "notfound" template can report the missing
* resource with a Velocity reference, like:
* <code>$missingResource</code>
* </p>
*
* @author <a href="mailto:[email protected]">Will Glass-Husain</a>
* @version $Id: IncludeNotFound.java 809816 2009-09-01 05:14:27Z nbubna $
* @since 1.5
*/
public class IncludeNotFound implements IncludeEventHandler,RuntimeServicesAware,ContextAware {
private static final String DEFAULT_NOT_FOUND = "notfound.vm";
private static final String PROPERTY_NOT_FOUND = "eventhandler.include.notfound";
private RuntimeServices rs = null;
String notfound;
Context context;
/**
* Chseck to see if included file exists, and display "not found" page if it
* doesn't. If "not found" page does not exist, log an error and return
* null.
*
* @param includeResourcePath
* @param currentResourcePath
* @param directiveName
* @return message.
*/
public String includeEvent(
String includeResourcePath,
String currentResourcePath,
String directiveName)
{
/**
* check to see if page exists
*/
boolean exists = (rs.getLoaderNameForResource(includeResourcePath) != null);
if (!exists)
{
context.put("missingResource", includeResourcePath);
if (rs.getLoaderNameForResource(notfound) != null)
{
return notfound;
}
else
{
/**
* can't find not found, so display nothing
*/
rs.getLog().error("Can't find include not found page: " + notfound);
return null;
}
}
else
return includeResourcePath;
}
/**
* @see org.apache.velocity.util.RuntimeServicesAware#setRuntimeServices(org.apache.velocity.runtime.RuntimeServices)
*/
public void setRuntimeServices(RuntimeServices rs)
{
this.rs = rs;
notfound = StringUtils.nullTrim(rs.getString(PROPERTY_NOT_FOUND, DEFAULT_NOT_FOUND));
}
/**
* @see org.apache.velocity.util.ContextAware#setContext(org.apache.velocity.context.Context)
*/
public void setContext(Context context)
{
this.context = context;
}
}
|