Java tutorial
/* Copyright 2004, 2005, 2006 Acegi Technology Pty Limited * * Licensed 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.acegisecurity.acl; import org.acegisecurity.Authentication; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.beans.factory.InitializingBean; import org.springframework.util.Assert; import java.util.Iterator; import java.util.List; /** * Iterates through a list of {@link AclProvider}s to locate the ACLs that apply to a given domain object instance.<P>If * no compatible provider is found, it is assumed that no ACLs apply for the specified domain object instance and * <code>null</code> is returned.</p> * * @author Ben Alex * @version $Id: AclProviderManager.java 1496 2006-05-23 13:38:33Z benalex $ */ public class AclProviderManager implements AclManager, InitializingBean { //~ Static fields/initializers ===================================================================================== private static final Log logger = LogFactory.getLog(AclProviderManager.class); //~ Instance fields ================================================================================================ private List providers; //~ Methods ======================================================================================================== public void afterPropertiesSet() throws Exception { checkIfValidList(this.providers); } private void checkIfValidList(List listToCheck) { Assert.notEmpty(listToCheck, "A list of AclManagers is required"); } public AclEntry[] getAcls(Object domainInstance) { Assert.notNull(domainInstance, "domainInstance is null - violating interface contract"); Iterator iter = providers.iterator(); while (iter.hasNext()) { AclProvider provider = (AclProvider) iter.next(); if (provider.supports(domainInstance)) { if (logger.isDebugEnabled()) { logger.debug("ACL lookup using " + provider.getClass().getName()); } return provider.getAcls(domainInstance); } } if (logger.isDebugEnabled()) { logger.debug("No AclProvider found for " + domainInstance.toString()); } return null; } public AclEntry[] getAcls(Object domainInstance, Authentication authentication) { Assert.notNull(domainInstance, "domainInstance is null - violating interface contract"); Assert.notNull(authentication, "authentication is null - violating interface contract"); Iterator iter = providers.iterator(); while (iter.hasNext()) { AclProvider provider = (AclProvider) iter.next(); if (provider.supports(domainInstance)) { if (logger.isDebugEnabled()) { logger.debug("ACL lookup using " + provider.getClass().getName()); } return provider.getAcls(domainInstance, authentication); } else { if (logger.isDebugEnabled()) { logger.debug("Provider " + provider.toString() + " does not support " + domainInstance); } } } if (logger.isDebugEnabled()) { logger.debug("No AclProvider found for " + domainInstance.toString()); } return null; } public List getProviders() { return this.providers; } /** * Sets the {@link AclProvider} objects to be used for ACL determinations. * * @param newList that should be used for ACL determinations * * @throws IllegalArgumentException if an invalid provider was included in the list */ public void setProviders(List newList) { checkIfValidList(newList); Iterator iter = newList.iterator(); while (iter.hasNext()) { Object currentObject = null; try { currentObject = iter.next(); AclProvider attemptToCast = (AclProvider) currentObject; } catch (ClassCastException cce) { throw new IllegalArgumentException( "AclProvider " + currentObject.getClass().getName() + " must implement AclProvider"); } } this.providers = newList; } }