/*
* 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.
*
*/
package org.apache.lenya.ac.impl;
import java.util.HashMap;
import java.util.Map;
import org.apache.avalon.framework.activity.Disposable;
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.service.ServiceException;
import org.apache.avalon.framework.service.ServiceSelector;
import org.apache.lenya.ac.AccessControlException;
import org.apache.lenya.ac.AccessController;
import org.apache.lenya.ac.AccessControllerResolver;
/**
* Access controller resolver composed of other access controller resolvers.
* The member resolvers are called one after the other to resolve the access controllers.
*
* @version $Id: ComposableAccessControllerResolver.java 473861 2006-11-12 03:51:14Z gregor $
*/
public class ComposableAccessControllerResolver
extends AbstractAccessControllerResolver
implements Configurable, Disposable {
/**
* @see org.apache.lenya.ac.impl.AbstractAccessControllerResolver#doResolveAccessController(java.lang.String)
*/
public AccessController doResolveAccessController(String url) throws AccessControlException {
AccessController controller = null;
try {
if (this.selector == null) {
this.selector =
(ServiceSelector) getManager().lookup(AccessControllerResolver.ROLE + "Selector");
}
String[] types = getResolverTypes();
int i = 0;
while (controller == null && i < types.length) {
getLogger().debug("Trying to resolve AC resolver for type [" + types[i] + "]");
AccessControllerResolver resolver =
(AccessControllerResolver) this.selector.select(types[i]);
controller = resolver.resolveAccessController(url);
setResolver(controller, resolver);
getLogger().debug("Resolved access controller [" + controller + "]");
i++;
}
} catch (ServiceException e) {
throw new AccessControlException(e);
}
return controller;
}
private Map controllerToResolver = new HashMap();
/**
* @see org.apache.lenya.ac.AccessControllerResolver#release(org.apache.lenya.ac.AccessController)
*/
public void release(AccessController controller) {
assert controller != null;
AccessControllerResolver resolver = getResolver(controller);
resolver.release(controller);
this.selector.release(resolver);
}
/**
* Returns the access controller resolver that was used to resolve a
* specific access controller.
* @param controller The access controller.
* @return An AC resolver.
*/
protected AccessControllerResolver getResolver(AccessController controller) {
AccessControllerResolver resolver =
(AccessControllerResolver) this.controllerToResolver.get(controller);
return resolver;
}
/**
* Sets the access controller resolver that was used to resolve a
* specific access controller.
* @param controller The access controller.
* @param resolver An AC resolver.
*/
protected void setResolver(AccessController controller, AccessControllerResolver resolver) {
this.controllerToResolver.put(controller, resolver);
}
protected static final String RESOLVER_ELEMENT = "resolver";
protected static final String TYPE_ATTRIBUTE = "type";
private String[] resolverTypes;
private ServiceSelector selector;
/**
* @see org.apache.avalon.framework.configuration.Configurable#configure(org.apache.avalon.framework.configuration.Configuration)
*/
public void configure(Configuration configuration) throws ConfigurationException {
Configuration[] accessControllerConfigs = configuration.getChildren(RESOLVER_ELEMENT);
this.resolverTypes = new String[accessControllerConfigs.length];
for (int i = 0; i < accessControllerConfigs.length; i++) {
this.resolverTypes[i] = accessControllerConfigs[i].getAttribute(TYPE_ATTRIBUTE);
}
}
/**
* Returns the access controller types.
* @return A string array.
*/
protected String[] getResolverTypes() {
return this.resolverTypes;
}
/**
* @see org.apache.avalon.framework.activity.Disposable#dispose()
*/
public void dispose() {
if (this.selector != null) {
getManager().release(this.selector);
}
}
}