/*
* 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.springframework.security.acls.domain;
import java.io.Serializable;
import net.sf.ehcache.CacheException;
import net.sf.ehcache.Ehcache;
import net.sf.ehcache.Element;
import org.springframework.security.acls.model.AclCache;
import org.springframework.security.acls.model.MutableAcl;
import org.springframework.security.acls.model.ObjectIdentity;
import org.springframework.security.acls.model.PermissionGrantingStrategy;
import org.springframework.security.util.FieldUtils;
import org.springframework.util.Assert;
/**
* Simple implementation of {@link AclCache} that delegates to EH-CACHE.
* <p>
* Designed to handle the transient fields in {@link AclImpl}. Note that this
* implementation assumes all {@link AclImpl} instances share the same
* {@link PermissionGrantingStrategy} and {@link AclAuthorizationStrategy} instances.
*
* @author Ben Alex
*/
public class EhCacheBasedAclCache implements AclCache {
// ~ Instance fields
// ================================================================================================
private final Ehcache cache;
private PermissionGrantingStrategy permissionGrantingStrategy;
private AclAuthorizationStrategy aclAuthorizationStrategy;
// ~ Constructors
// ===================================================================================================
public EhCacheBasedAclCache(Ehcache cache,
PermissionGrantingStrategy permissionGrantingStrategy,
AclAuthorizationStrategy aclAuthorizationStrategy) {
Assert.notNull(cache, "Cache required");
Assert.notNull(permissionGrantingStrategy, "PermissionGrantingStrategy required");
Assert.notNull(aclAuthorizationStrategy, "AclAuthorizationStrategy required");
this.cache = cache;
this.permissionGrantingStrategy = permissionGrantingStrategy;
this.aclAuthorizationStrategy = aclAuthorizationStrategy;
}
// ~ Methods
// ========================================================================================================
public void evictFromCache(Serializable pk) {
Assert.notNull(pk, "Primary key (identifier) required");
MutableAcl acl = getFromCache(pk);
if (acl != null) {
cache.remove(acl.getId());
cache.remove(acl.getObjectIdentity());
}
}
public void evictFromCache(ObjectIdentity objectIdentity) {
Assert.notNull(objectIdentity, "ObjectIdentity required");
MutableAcl acl = getFromCache(objectIdentity);
if (acl != null) {
cache.remove(acl.getId());
cache.remove(acl.getObjectIdentity());
}
}
public MutableAcl getFromCache(ObjectIdentity objectIdentity) {
Assert.notNull(objectIdentity, "ObjectIdentity required");
Element element = null;
try {
element = cache.get(objectIdentity);
}
catch (CacheException ignored) {
}
if (element == null) {
return null;
}
return initializeTransientFields((MutableAcl) element.getValue());
}
public MutableAcl getFromCache(Serializable pk) {
Assert.notNull(pk, "Primary key (identifier) required");
Element element = null;
try {
element = cache.get(pk);
}
catch (CacheException ignored) {
}
if (element == null) {
return null;
}
return initializeTransientFields((MutableAcl) element.getValue());
}
public void putInCache(MutableAcl acl) {
Assert.notNull(acl, "Acl required");
Assert.notNull(acl.getObjectIdentity(), "ObjectIdentity required");
Assert.notNull(acl.getId(), "ID required");
if (this.aclAuthorizationStrategy == null) {
if (acl instanceof AclImpl) {
this.aclAuthorizationStrategy = (AclAuthorizationStrategy) FieldUtils
.getProtectedFieldValue("aclAuthorizationStrategy", acl);
this.permissionGrantingStrategy = (PermissionGrantingStrategy) FieldUtils
.getProtectedFieldValue("permissionGrantingStrategy", acl);
}
}
if ((acl.getParentAcl() != null) && (acl.getParentAcl() instanceof MutableAcl)) {
putInCache((MutableAcl) acl.getParentAcl());
}
cache.put(new Element(acl.getObjectIdentity(), acl));
cache.put(new Element(acl.getId(), acl));
}
private MutableAcl initializeTransientFields(MutableAcl value) {
if (value instanceof AclImpl) {
FieldUtils.setProtectedFieldValue("aclAuthorizationStrategy", value,
this.aclAuthorizationStrategy);
FieldUtils.setProtectedFieldValue("permissionGrantingStrategy", value,
this.permissionGrantingStrategy);
}
if (value.getParentAcl() != null) {
initializeTransientFields((MutableAcl) value.getParentAcl());
}
return value;
}
public void clearCache() {
cache.removeAll();
}
}