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2758df8308
103438: Working towards a fix for ACE-3948: BM-0004: Factor out select on alf_content_url table during file creation
- Complement the 'getOrCreate' EntityCache calls with 'createOrGet'
- Cleanup of ContentDataDAOImpl code before further changes: tabs, @Override, unused code, etc
git-svn-id: https://svn.alfresco.com/repos/alfresco-enterprise/alfresco/HEAD/root@103622 c4b6b30b-aa2e-2d43-bbcb-ca4b014f7261
802 lines
31 KiB
Java
802 lines
31 KiB
Java
/*
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* Copyright (C) 2005-2010 Alfresco Software Limited.
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*
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* This file is part of Alfresco
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*
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* Alfresco is free software: you can redistribute it and/or modify
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* it under the terms of the GNU Lesser General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* Alfresco is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public License
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* along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
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*/
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package org.alfresco.repo.cache.lookup;
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import java.io.Serializable;
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import java.sql.Savepoint;
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import org.alfresco.repo.cache.SimpleCache;
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import org.alfresco.repo.domain.control.ControlDAO;
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import org.alfresco.repo.transaction.RetryingTransactionHelper;
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import org.alfresco.util.Pair;
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import org.springframework.dao.ConcurrencyFailureException;
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import org.springframework.extensions.surf.util.ParameterCheck;
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/**
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* A cache for two-way lookups of database entities. These are characterized by having a unique
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* key (perhaps a database ID) and a separate unique key that identifies the object. If no cache
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* is given, then all calls are passed through to the backing DAO.
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* <p>
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* The keys must have good <code>equals</code> and </code>hashCode</code> implementations and
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* must respect the case-sensitivity of the use-case.
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* <p>
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* All keys will be unique to the given cache region, allowing the cache to be shared
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* between instances of this class.
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* <p>
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* Generics:
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* <ul>
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* <li>K: The database unique identifier.</li>
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* <li>V: The value stored against K.</li>
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* <li>VK: The a value-derived key that will be used as a cache key when caching K for lookups by V.
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* This can be the value itself if it is itself a good key.</li>
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* </ul>
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*
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* @author Derek Hulley
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* @since 3.2
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*/
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public class EntityLookupCache<K extends Serializable, V extends Object, VK extends Serializable>
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{
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/**
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* Interface to support lookups of the entities using keys and values.
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*/
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public static interface EntityLookupCallbackDAO<K1 extends Serializable, V1 extends Object, VK1 extends Serializable>
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{
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/**
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* Resolve the given value into a unique value key that can be used to find the entity's ID.
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* A return value should be small and efficient; don't return a value if this is not possible.
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* <p/>
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* Implementations will often return the value itself, provided that the value is both
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* serializable and has a good <code>equals</code> and <code>hashCode</code>.
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* <p/>
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* Were no adequate key can be generated for the value, then <tt>null</tt> can be returned.
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* In this case, the {@link #findByValue(Object) findByValue} method might not even do a search
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* and just return <tt>null</tt> itself i.e. if it is difficult to look the value up in storage
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* then it is probably difficult to generate a cache key from it, too.. In this scenario, the
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* cache will be purely for key-based lookups
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*
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* @param value the full value being keyed (never <tt>null</tt>)
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* @return Returns the business key representing the entity, or <tt>null</tt>
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* if an economical key cannot be generated.
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*/
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VK1 getValueKey(V1 value);
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/**
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* Find an entity for a given key.
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*
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* @param key the key (ID) used to identify the entity (never <tt>null</tt>)
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* @return Return the entity or <tt>null</tt> if no entity is exists for the ID
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*/
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Pair<K1, V1> findByKey(K1 key);
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/**
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* Find and entity using the given value key. The <code>equals</code> and <code>hashCode</code>
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* methods of the value object should respect case-sensitivity in the same way that this
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* lookup treats case-sensitivity i.e. if the <code>equals</code> method is <b>case-sensitive</b>
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* then this method should look the entity up using a <b>case-sensitive</b> search.
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* <p/>
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* Since this is a cache backed by some sort of database, <tt>null</tt> values are allowed by the
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* cache. The implementation of this method can throw an exception if <tt>null</tt> is not
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* appropriate for the use-case.
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* <p/>
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* If the search is impossible or expensive, this method should just return <tt>null</tt>. This
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* would usually be the case if the {@link #getValueKey(Object) getValueKey} method also returned
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* <tt>null</tt> i.e. if it is difficult to look the value up in storage then it is probably
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* difficult to generate a cache key from it, too.
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*
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* @param value the value (business object) used to identify the entity (<tt>null</tt> allowed).
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* @return Return the entity or <tt>null</tt> if no entity matches the given value
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*/
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Pair<K1, V1> findByValue(V1 value);
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/**
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* Create an entity using the given values. It is valid to assume that the entity does not exist
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* within the current transaction at least.
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* <p/>
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* Since persistence mechanisms often allow <tt>null</tt> values, these can be expected here. The
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* implementation must throw an exception if <tt>null</tt> is not allowed for the specific use-case.
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*
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* @param value the value (business object) used to identify the entity (<tt>null</tt> allowed).
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* @return Return the newly-created entity ID-value pair
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*/
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Pair<K1, V1> createValue(V1 value);
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/**
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* Update the entity identified by the given key.
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* <p/>
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* It is up to the client code to decide if a <tt>0</tt> return value indicates a concurrency violation
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* or not.
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*
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* @param key the existing key (ID) used to identify the entity (never <tt>null</tt>)
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* @param value the new value
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* @return Returns the row update count.
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* @throws UnsupportedOperationException if entity updates are not supported
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*/
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int updateValue(K1 key, V1 value);
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/**
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* Delete an entity for the given key.
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* <p/>
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* It is up to the client code to decide if a <tt>0</tt> return value indicates a concurrency violation
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* or not.
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*
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* @param key the key (ID) used to identify the entity (never <tt>null</tt>)
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* @return Returns the row deletion count.
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* @throws UnsupportedOperationException if entity deletion is not supported
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*/
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int deleteByKey(K1 key);
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/**
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* Delete an entity for the given value.
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* <p/>
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* It is up to the client code to decide if a <tt>0</tt> return value indicates a concurrency violation
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* or not.
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*
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* @param value the value (business object) used to identify the enitity (<tt>null</tt> allowed)
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* @return Returns the row deletion count.
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* @throws UnsupportedOperationException if entity deletion is not supported
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*/
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int deleteByValue(V1 value);
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}
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/**
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* Adaptor for implementations that support immutable entities. The update and delete operations
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* throw {@link UnsupportedOperationException}.
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*
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* @author Derek Hulley
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* @since 3.2
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*/
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public static abstract class EntityLookupCallbackDAOAdaptor<K2 extends Serializable, V2 extends Object, VK2 extends Serializable>
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implements EntityLookupCallbackDAO<K2, V2, VK2>
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{
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/**
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* This implementation never finds a value and is backed by {@link #getValueKey(Object)} returning nothing.
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*
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* @return Returns <tt>null</tt> always
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*/
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public Pair<K2, V2> findByValue(V2 value)
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{
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return null;
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}
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/**
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* This implementation does not find by value and is backed by {@link #findByValue(Object)} returning nothing.
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*
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* @return Returns <tt>null</tt> always
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*/
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public VK2 getValueKey(V2 value)
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{
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return null;
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}
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/**
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* Disallows the operation.
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*
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* @throws UnsupportedOperationException always
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*/
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public int updateValue(K2 key, V2 value)
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{
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throw new UnsupportedOperationException();
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}
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/**
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* Disallows the operation.
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*
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* @throws UnsupportedOperationException always
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*/
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public int deleteByKey(K2 key)
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{
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throw new UnsupportedOperationException("Entity deletion by key is not supported");
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}
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/**
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* Disallows the operation.
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*
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* @throws UnsupportedOperationException always
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*/
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public int deleteByValue(V2 value)
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{
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throw new UnsupportedOperationException("Entity deletion by value is not supported");
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}
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}
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/**
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* A valid <code>null</code> value i.e. a value that has been <u>persisted</u> as null.
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*/
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private static final Serializable VALUE_NULL = "@@VALUE_NULL@@";
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/**
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* A value that was not found or persisted.
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*/
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private static final Serializable VALUE_NOT_FOUND = "@@VALUE_NOT_FOUND@@";
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/**
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* The cache region that will be used (see {@link CacheRegionKey}) in all the cache keys
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*/
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private static final String CACHE_REGION_DEFAULT = "DEFAULT";
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private final SimpleCache<Serializable, Object> cache;
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private final EntityLookupCallbackDAO<K, V, VK> entityLookup;
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private final String cacheRegion;
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/**
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* Construct the lookup cache <b>without any cache</b>. All calls are passed directly to the
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* underlying DAO entity lookup.
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*
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* @param entityLookup the instance that is able to find and persist entities
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*/
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public EntityLookupCache(EntityLookupCallbackDAO<K, V, VK> entityLookup)
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{
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this(null, CACHE_REGION_DEFAULT, entityLookup);
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}
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/**
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* Construct the lookup cache, using the {@link #CACHE_REGION_DEFAULT default cache region}.
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*
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* @param cache the cache that will back the two-way lookups
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* @param entityLookup the instance that is able to find and persist entities
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*/
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@SuppressWarnings("rawtypes")
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public EntityLookupCache(SimpleCache cache, EntityLookupCallbackDAO<K, V, VK> entityLookup)
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{
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this(cache, CACHE_REGION_DEFAULT, entityLookup);
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}
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/**
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* Construct the lookup cache, using the given cache region.
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* <p>
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* All keys will be unique to the given cache region, allowing the cache to be shared
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* between instances of this class.
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*
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* @param cache the cache that will back the two-way lookups; <tt>null</tt> to have no backing
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* in a cache.
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* @param cacheRegion the region within the cache to use.
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* @param entityLookup the instance that is able to find and persist entities
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*/
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@SuppressWarnings({ "rawtypes", "unchecked" })
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public EntityLookupCache(SimpleCache cache, String cacheRegion, EntityLookupCallbackDAO<K, V, VK> entityLookup)
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{
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ParameterCheck.mandatory("cacheRegion", cacheRegion);
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ParameterCheck.mandatory("entityLookup", entityLookup);
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this.cache = cache;
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this.cacheRegion = cacheRegion;
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this.entityLookup = entityLookup;
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}
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/**
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* Find the entity associated with the given key.
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* The {@link EntityLookupCallbackDAO#findByKey(Serializable) entity callback} will be used if necessary.
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* <p/>
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* It is up to the client code to decide if a <tt>null</tt> return value indicates a concurrency violation
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* or not; the former would normally result in a concurrency-related exception such as
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* {@link ConcurrencyFailureException}.
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*
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* @param key The entity key, which may be valid or invalid (<tt>null</tt> not allowed)
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* @return Returns the key-value pair or <tt>null</tt> if the key doesn't reference an entity
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*/
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@SuppressWarnings("unchecked")
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public Pair<K, V> getByKey(K key)
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{
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if (key == null)
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{
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throw new IllegalArgumentException("An entity lookup key may not be null");
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}
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// Handle missing cache
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if (cache == null)
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{
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return entityLookup.findByKey(key);
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}
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CacheRegionKey keyCacheKey = new CacheRegionKey(cacheRegion, key);
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// Look in the cache
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V value = (V) cache.get(keyCacheKey);
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if (value != null)
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{
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if (value.equals(VALUE_NOT_FOUND))
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{
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// We checked before
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return null;
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}
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else if (value.equals(VALUE_NULL))
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{
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return new Pair<K, V>(key, null);
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}
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else
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{
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return new Pair<K, V>(key, value);
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}
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}
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// Resolve it
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Pair<K, V> entityPair = entityLookup.findByKey(key);
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if (entityPair == null)
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{
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// Cache "not found"
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cache.put(keyCacheKey, VALUE_NOT_FOUND);
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}
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else
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{
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value = entityPair.getSecond();
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// Get the value key
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VK valueKey = (value == null) ? (VK)VALUE_NULL : entityLookup.getValueKey(value);
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// Check if the value has a good key
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if (valueKey != null)
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{
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CacheRegionValueKey valueCacheKey = new CacheRegionValueKey(cacheRegion, valueKey);
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// The key is good, so we can cache the value
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cache.put(valueCacheKey, key);
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}
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cache.put(
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keyCacheKey,
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(value == null ? VALUE_NULL : value));
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}
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// Done
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return entityPair;
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}
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/**
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* Find the entity associated with the given value.
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* The {@link EntityLookupCallbackDAO#findByValue(Object) entity callback} will be used if no entry exists in the cache.
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* <p/>
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* It is up to the client code to decide if a <tt>null</tt> return value indicates a concurrency violation
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* or not; the former would normally result in a concurrency-related exception such as
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* {@link ConcurrencyFailureException}.
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*
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* @param value The entity value, which may be valid or invalid (<tt>null</tt> is allowed)
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* @return Returns the key-value pair or <tt>null</tt> if the value doesn't reference an entity
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*/
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@SuppressWarnings("unchecked")
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public Pair<K, V> getByValue(V value)
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{
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// Handle missing cache
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if (cache == null)
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{
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return entityLookup.findByValue(value);
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}
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// Get the value key.
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// The cast to (VK) is counter-intuitive, but works because they're all just Serializable
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// It's nasty, but hidden from the cache client code.
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VK valueKey = (value == null) ? (VK)VALUE_NULL : entityLookup.getValueKey(value);
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// Check if the value has a good key
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if (valueKey == null)
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{
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return entityLookup.findByValue(value);
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}
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// Look in the cache
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CacheRegionValueKey valueCacheKey = new CacheRegionValueKey(cacheRegion, valueKey);
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K key = (K) cache.get(valueCacheKey);
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// Check if we have looked this up already
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if (key != null)
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{
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// We checked before and ...
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if (key.equals(VALUE_NOT_FOUND))
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{
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// ... it didn't exist
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return null;
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}
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else
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{
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// ... it did exist
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return getByKey(key);
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}
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}
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// Resolve it
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Pair<K, V> entityPair = entityLookup.findByValue(value);
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if (entityPair == null)
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{
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// Cache "not found"
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cache.put(valueCacheKey, VALUE_NOT_FOUND);
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}
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else
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{
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key = entityPair.getFirst();
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// Cache the key
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cache.put(valueCacheKey, key);
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cache.put(
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new CacheRegionKey(cacheRegion, key),
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(entityPair.getSecond() == null ? VALUE_NULL : entityPair.getSecond()));
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}
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// Done
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return entityPair;
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}
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/**
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* Attempt to create the entity and, failing that, look it up.<br/>
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* This method takes the opposite approach to {@link #getOrCreateByValue(Object)}, which assumes the entity's
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* existence: in this case the entity is assumed to NOT exist.
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* The {@link EntityLookupCallbackDAO#createValue(Object)} and {@link EntityLookupCallbackDAO#findByValue(Object)}
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* will be used if necessary.<br/>
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* <p/>
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* Use this method when the data involved is seldom reused.
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*
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* @param value The entity value (<tt>null</tt> is allowed)
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* @param controlDAO an essential DAO required in order to ensure a transactionally-safe attempt at data creation
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* @return Returns the key-value pair (new or existing and never <tt>null</tt>)
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*/
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public Pair<K, V> createOrGetByValue(V value, ControlDAO controlDAO)
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{
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if (controlDAO == null)
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{
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throw new IllegalArgumentException("The ControlDAO is required in order to perform a safe attempted insert.");
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}
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Savepoint savepoint = controlDAO.createSavepoint("EntityLookupCache.createOrGetByValue");
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try
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{
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Pair<K, V> entityPair = entityLookup.createValue(value);
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controlDAO.releaseSavepoint(savepoint);
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// Cache it
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if (cache != null)
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{
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cache.put(
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new CacheRegionKey(cacheRegion, entityPair.getFirst()),
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(entityPair.getSecond() == null ? VALUE_NULL : entityPair.getSecond()));
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}
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// It's been created and cached
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return entityPair;
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}
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catch (Exception e)
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{
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controlDAO.rollbackToSavepoint(savepoint);
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// Fall through to the usual way, which should find it if the failure cause was a duplicate key
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return getOrCreateByValue(value);
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}
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}
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/**
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* Find the entity associated with the given value and create it if it doesn't exist.
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* The {@link EntityLookupCallbackDAO#findByValue(Object)} and {@link EntityLookupCallbackDAO#createValue(Object)}
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* will be used if necessary.
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*
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* @param value The entity value (<tt>null</tt> is allowed)
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* @return Returns the key-value pair (new or existing and never <tt>null</tt>)
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*/
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@SuppressWarnings("unchecked")
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public Pair<K, V> getOrCreateByValue(V value)
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{
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// Handle missing cache
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if (cache == null)
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{
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Pair<K, V> entityPair = entityLookup.findByValue(value);
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if (entityPair == null)
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{
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entityPair = entityLookup.createValue(value);
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}
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return entityPair;
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}
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// Get the value key
|
|
// The cast to (VK) is counter-intuitive, but works because they're all just Serializable.
|
|
// It's nasty, but hidden from the cache client code.
|
|
VK valueKey = (value == null) ? (VK)VALUE_NULL : entityLookup.getValueKey(value);
|
|
// Check if the value has a good key
|
|
if (valueKey == null)
|
|
{
|
|
Pair<K, V> entityPair = entityLookup.findByValue(value);
|
|
if (entityPair == null)
|
|
{
|
|
entityPair = entityLookup.createValue(value);
|
|
// Cache the value
|
|
cache.put(
|
|
new CacheRegionKey(cacheRegion, entityPair.getFirst()),
|
|
(entityPair.getSecond() == null ? VALUE_NULL : entityPair.getSecond()));
|
|
}
|
|
return entityPair;
|
|
}
|
|
|
|
// Look in the cache
|
|
CacheRegionValueKey valueCacheKey = new CacheRegionValueKey(cacheRegion, valueKey);
|
|
K key = (K) cache.get(valueCacheKey);
|
|
// Check if the value is already mapped to a key
|
|
if (key != null && !key.equals(VALUE_NOT_FOUND))
|
|
{
|
|
return getByKey(key);
|
|
}
|
|
// Resolve it
|
|
Pair<K, V> entityPair = entityLookup.findByValue(value);
|
|
if (entityPair == null)
|
|
{
|
|
// Create it
|
|
entityPair = entityLookup.createValue(value);
|
|
}
|
|
key = entityPair.getFirst();
|
|
// Cache the key and value
|
|
cache.put(valueCacheKey, key);
|
|
cache.put(
|
|
new CacheRegionKey(cacheRegion, key),
|
|
(value == null ? VALUE_NULL : value));
|
|
// Done
|
|
return entityPair;
|
|
}
|
|
|
|
/**
|
|
* Update the entity associated with the given key.
|
|
* The {@link EntityLookupCallbackDAO#updateValue(Serializable, Object)} callback
|
|
* will be used if necessary.
|
|
* <p/>
|
|
* It is up to the client code to decide if a <tt>0</tt> return value indicates a concurrency violation
|
|
* or not; usually the former will generate {@link ConcurrencyFailureException} or something recognised
|
|
* by the {@link RetryingTransactionHelper#RETRY_EXCEPTIONS RetryingTransactionHelper}.
|
|
*
|
|
* @param key The entity key, which may be valid or invalid (<tt>null</tt> not allowed)
|
|
* @param value The new entity value (may be <tt>null</tt>)
|
|
* @return Returns the row update count.
|
|
*/
|
|
@SuppressWarnings("unchecked")
|
|
public int updateValue(K key, V value)
|
|
{
|
|
// Handle missing cache
|
|
if (cache == null)
|
|
{
|
|
return entityLookup.updateValue(key, value);
|
|
}
|
|
|
|
// Remove entries for the key (bidirectional removal removes the old value as well)
|
|
// but leave the key as it will get updated
|
|
removeByKey(key, false);
|
|
|
|
// Do the update
|
|
int updateCount = entityLookup.updateValue(key, value);
|
|
if (updateCount == 0)
|
|
{
|
|
// Nothing was done
|
|
return updateCount;
|
|
}
|
|
|
|
// Get the value key.
|
|
VK valueKey = (value == null) ? (VK)VALUE_NULL : entityLookup.getValueKey(value);
|
|
// Check if the value has a good key
|
|
if (valueKey != null)
|
|
{
|
|
// There is a good value key, cache by value
|
|
CacheRegionValueKey valueCacheKey = new CacheRegionValueKey(cacheRegion, valueKey);
|
|
cache.put(valueCacheKey, key);
|
|
}
|
|
// Cache by key
|
|
cache.put(
|
|
new CacheRegionKey(cacheRegion, key),
|
|
(value == null ? VALUE_NULL : value));
|
|
// Done
|
|
return updateCount;
|
|
}
|
|
|
|
/**
|
|
* Cache-only operation: Get the key for a given value key (note: not 'value' but 'value key').
|
|
*
|
|
* @param valueKey The entity value key, which must be valid (<tt>null</tt> not allowed)
|
|
* @return The entity key (may be <tt>null</tt>)
|
|
*/
|
|
@SuppressWarnings("unchecked")
|
|
public K getKey(VK valueKey)
|
|
{
|
|
// There is a good value key, cache by value
|
|
CacheRegionValueKey valueCacheKey = new CacheRegionValueKey(cacheRegion, valueKey);
|
|
K key = (K) cache.get(valueCacheKey);
|
|
// Check if we have looked this up already
|
|
if (key != null && key.equals(VALUE_NOT_FOUND))
|
|
{
|
|
key = null;
|
|
}
|
|
return key;
|
|
}
|
|
|
|
/**
|
|
* Cache-only operation: Get the value for a given key
|
|
*
|
|
* @param key The entity key, which may be valid or invalid (<tt>null</tt> not allowed)
|
|
* @return The entity value (may be <tt>null</tt>)
|
|
*/
|
|
@SuppressWarnings("unchecked")
|
|
public V getValue(K key)
|
|
{
|
|
CacheRegionKey keyCacheKey = new CacheRegionKey(cacheRegion, key);
|
|
// Look in the cache
|
|
V value = (V) cache.get(keyCacheKey);
|
|
if (value == null)
|
|
{
|
|
return null;
|
|
}
|
|
else if (value.equals(VALUE_NOT_FOUND))
|
|
{
|
|
// We checked before
|
|
return null;
|
|
}
|
|
else if (value.equals(VALUE_NULL))
|
|
{
|
|
return null;
|
|
}
|
|
else
|
|
{
|
|
return value;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Cache-only operation: Update the cache's value
|
|
*
|
|
* @param key The entity key, which may be valid or invalid (<tt>null</tt> not allowed)
|
|
* @param value The new entity value (may be <tt>null</tt>)
|
|
*/
|
|
@SuppressWarnings("unchecked")
|
|
public void setValue(K key, V value)
|
|
{
|
|
// Handle missing cache
|
|
if (cache == null)
|
|
{
|
|
return;
|
|
}
|
|
|
|
// Remove entries for the key (bidirectional removal removes the old value as well)
|
|
// but leave the key as it will get updated
|
|
removeByKey(key, false);
|
|
|
|
// Get the value key.
|
|
VK valueKey = (value == null) ? (VK)VALUE_NULL : entityLookup.getValueKey(value);
|
|
// Check if the value has a good key
|
|
if (valueKey != null)
|
|
{
|
|
// There is a good value key, cache by value
|
|
CacheRegionValueKey valueCacheKey = new CacheRegionValueKey(cacheRegion, valueKey);
|
|
cache.put(valueCacheKey, key);
|
|
}
|
|
// Cache by key
|
|
cache.put(
|
|
new CacheRegionKey(cacheRegion, key),
|
|
(value == null ? VALUE_NULL : value));
|
|
// Done
|
|
}
|
|
|
|
/**
|
|
* Delete the entity associated with the given key.
|
|
* The {@link EntityLookupCallbackDAO#deleteByKey(Serializable)} callback will be used if necessary.
|
|
* <p/>
|
|
* It is up to the client code to decide if a <tt>0</tt> return value indicates a concurrency violation
|
|
* or not; usually the former will generate {@link ConcurrencyFailureException} or something recognised
|
|
* by the {@link RetryingTransactionHelper#RETRY_EXCEPTIONS RetryingTransactionHelper}.
|
|
*
|
|
* @param key the entity key, which may be valid or invalid (<tt>null</tt> not allowed)
|
|
* @return Returns the row deletion count
|
|
*/
|
|
public int deleteByKey(K key)
|
|
{
|
|
// Handle missing cache
|
|
if (cache == null)
|
|
{
|
|
return entityLookup.deleteByKey(key);
|
|
}
|
|
|
|
// Remove entries for the key (bidirectional removal removes the old value as well)
|
|
removeByKey(key);
|
|
|
|
// Do the delete
|
|
return entityLookup.deleteByKey(key);
|
|
}
|
|
|
|
/**
|
|
* Delete the entity having the given value..
|
|
* The {@link EntityLookupCallbackDAO#deleteByValue(Object)} callback will be used if necessary.
|
|
* <p/>
|
|
* It is up to the client code to decide if a <tt>0</tt> return value indicates a concurrency violation
|
|
* or not; usually the former will generate {@link ConcurrencyFailureException} or something recognised
|
|
* by the {@link RetryingTransactionHelper#RETRY_EXCEPTIONS RetryingTransactionHelper}.
|
|
*
|
|
* @param value the entity value, which may be valid or invalid (<tt>null</tt> allowed)
|
|
* @return Returns the row deletion count
|
|
*/
|
|
public int deleteByValue(V value)
|
|
{
|
|
// Handle missing cache
|
|
if (cache == null)
|
|
{
|
|
return entityLookup.deleteByValue(value);
|
|
}
|
|
|
|
// Remove entries for the value
|
|
removeByValue(value);
|
|
|
|
// Do the delete
|
|
return entityLookup.deleteByValue(value);
|
|
}
|
|
|
|
/**
|
|
* Cache-only operation: Remove all cache values associated with the given key.
|
|
*/
|
|
public void removeByKey(K key)
|
|
{
|
|
// Handle missing cache
|
|
if (cache == null)
|
|
{
|
|
return;
|
|
}
|
|
|
|
removeByKey(key, true);
|
|
}
|
|
|
|
/**
|
|
* Cache-only operation: Remove all cache values associated with the given key.
|
|
*
|
|
* @param removeKey <tt>true</tt> to remove the given key's entry
|
|
*/
|
|
@SuppressWarnings("unchecked")
|
|
private void removeByKey(K key, boolean removeKey)
|
|
{
|
|
CacheRegionKey keyCacheKey = new CacheRegionKey(cacheRegion, key);
|
|
V value = (V) cache.get(keyCacheKey);
|
|
if (value != null && !value.equals(VALUE_NOT_FOUND))
|
|
{
|
|
// Get the value key and remove it
|
|
VK valueKey = entityLookup.getValueKey(value);
|
|
if (valueKey != null)
|
|
{
|
|
CacheRegionValueKey valueCacheKey = new CacheRegionValueKey(cacheRegion, valueKey);
|
|
cache.remove(valueCacheKey);
|
|
}
|
|
}
|
|
if (removeKey)
|
|
{
|
|
cache.remove(keyCacheKey);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Cache-only operation: Remove all cache values associated with the given value
|
|
*
|
|
* @param value The entity value (<tt>null</tt> is allowed)
|
|
*/
|
|
@SuppressWarnings("unchecked")
|
|
public void removeByValue(V value)
|
|
{
|
|
// Handle missing cache
|
|
if (cache == null)
|
|
{
|
|
return;
|
|
}
|
|
|
|
// Get the value key
|
|
VK valueKey = (value == null) ? (VK)VALUE_NULL : entityLookup.getValueKey(value);
|
|
if (valueKey == null)
|
|
{
|
|
// No key generated for the value. There is nothing that can be done.
|
|
return;
|
|
}
|
|
// Look in the cache
|
|
CacheRegionValueKey valueCacheKey = new CacheRegionValueKey(cacheRegion, valueKey);
|
|
K key = (K) cache.get(valueCacheKey);
|
|
// Check if the value is already mapped to a key
|
|
if (key != null && !key.equals(VALUE_NOT_FOUND))
|
|
{
|
|
CacheRegionKey keyCacheKey = new CacheRegionKey(cacheRegion, key);
|
|
cache.remove(keyCacheKey);
|
|
}
|
|
cache.remove(valueCacheKey);
|
|
}
|
|
|
|
/**
|
|
* Cache-only operation: Remove all cache entries
|
|
* <p/>
|
|
* <b>NOTE:</b> This operation removes ALL entries for ALL cache regions.
|
|
*/
|
|
public void clear()
|
|
{
|
|
// Handle missing cache
|
|
if (cache == null)
|
|
{
|
|
return;
|
|
}
|
|
cache.clear();
|
|
}
|
|
}
|