001 /*
002 * JBoss DNA (http://www.jboss.org/dna)
003 * See the COPYRIGHT.txt file distributed with this work for information
004 * regarding copyright ownership. Some portions may be licensed
005 * to Red Hat, Inc. under one or more contributor license agreements.
006 * See the AUTHORS.txt file in the distribution for a full listing of
007 * individual contributors.
008 *
009 * JBoss DNA is free software. Unless otherwise indicated, all code in JBoss DNA
010 * is licensed to you under the terms of the GNU Lesser General Public License as
011 * published by the Free Software Foundation; either version 2.1 of
012 * the License, or (at your option) any later version.
013 *
014 * JBoss DNA is distributed in the hope that it will be useful,
015 * but WITHOUT ANY WARRANTY; without even the implied warranty of
016 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
017 * Lesser General Public License for more details.
018 *
019 * You should have received a copy of the GNU Lesser General Public
020 * License along with this software; if not, write to the Free
021 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
022 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
023 */
024 package org.jboss.dna.connector.store.jpa.util;
025
026 import java.util.HashMap;
027 import java.util.Map;
028 import java.util.Set;
029 import javax.persistence.EntityManager;
030 import net.jcip.annotations.NotThreadSafe;
031 import org.jboss.dna.connector.store.jpa.model.common.WorkspaceEntity;
032
033 /**
034 * A manager and cache for {@link WorkspaceEntity} objects.
035 *
036 * @author Randall Hauch
037 */
038 @NotThreadSafe
039 public class Workspaces {
040
041 private final EntityManager entityManager;
042 private final Map<String, WorkspaceEntity> cache = new HashMap<String, WorkspaceEntity>();
043
044 public Workspaces( EntityManager manager ) {
045 this.entityManager = manager;
046 }
047
048 /**
049 * Create a workspace with the supplied name.
050 *
051 * @param workspaceName the name of the workspace; may not be null
052 * @return the workspace entity, or null if there already was a workspace with the supplied name
053 */
054 public WorkspaceEntity create( String workspaceName ) {
055 assert workspaceName != null;
056 WorkspaceEntity entity = cache.get(workspaceName);
057 if (entity != null) return null;
058 entity = WorkspaceEntity.findByName(entityManager, workspaceName, false);
059 if (entity != null) return null;
060 // Create one ...
061 entity = WorkspaceEntity.findByName(entityManager, workspaceName, true);
062 cache.put(workspaceName, entity);
063 return entity;
064 }
065
066 /**
067 * Get the workspace with the supplied name, and optionally create a new one if missing.
068 *
069 * @param workspaceName the name of the workspace; never null
070 * @param createIfRequired true if the workspace should be created if there is no existing workspace with the supplied name
071 * @return the workspace entity, or null if no workspace existed with the supplied name and <code>createIfRequired</code> was
072 * false
073 */
074 public WorkspaceEntity get( String workspaceName,
075 boolean createIfRequired ) {
076 WorkspaceEntity entity = cache.get(workspaceName);
077 if (entity == null) {
078 entity = WorkspaceEntity.findByName(entityManager, workspaceName, createIfRequired);
079 if (entity != null) {
080 cache.put(workspaceName, entity);
081 }
082 }
083 return entity;
084 }
085
086 /**
087 * Find the set of names for the existing workspaces.
088 *
089 * @return the set of names; never null
090 */
091 public Set<String> getWorkspaceNames() {
092 return WorkspaceEntity.findAllNames(entityManager);
093 }
094
095 /**
096 * Remove the entity representation of the workspace. This does not remove any other data associated with the workspace other
097 * than the {@link WorkspaceEntity} record.
098 *
099 * @param workspaceName the name of the workspace; may not be null
100 * @return true if the workspace record was found and removed, or false if there was no workspace with the supplied name
101 */
102 public boolean destroy( String workspaceName ) {
103 assert workspaceName != null;
104 WorkspaceEntity entity = cache.remove(workspaceName);
105 if (entity == null) {
106 entity = WorkspaceEntity.findByName(entityManager, workspaceName, false);
107 }
108 if (entity != null) {
109 entityManager.remove(entity);
110 }
111 return entity != null;
112 }
113 }