eu.etaxonomy.taxeditor.cdmlib/src/main/java/org/hibernate/proxy/AbstractLazyInitializer.java

   1 /*
   2  * Hibernate, Relational Persistence for Idiomatic Java
   3  *
   4  * Copyright (c) 2008-2011, Red Hat Inc. or third-party contributors as
   5  * indicated by the @author tags or express copyright attribution
   6  * statements applied by the authors.  All third-party contributions are
   7  * distributed under license by Red Hat Inc.
   8  *
   9  * This copyrighted material is made available to anyone wishing to use, modify,
  10  * copy, or redistribute it subject to the terms and conditions of the GNU
  11  * Lesser General Public License, as published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  15  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
  16  * for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public License
  19  * along with this distribution; if not, write to:
  20  * Free Software Foundation, Inc.
  21  * 51 Franklin Street, Fifth Floor
  22  * Boston, MA  02110-1301  USA
  23  */
  24 package org.hibernate.proxy;
  25
  26 import java.io.Serializable;
  27
  28 import javax.naming.NamingException;
  29
  30 import org.hibernate.HibernateException;
  31 import org.hibernate.LazyInitializationException;
  32 import org.hibernate.Session;
  33 import org.hibernate.SessionException;
  34 import org.hibernate.TransientObjectException;
  35 import org.hibernate.engine.spi.EntityKey;
  36 import org.hibernate.engine.spi.SessionFactoryImplementor;
  37 import org.hibernate.engine.spi.SessionImplementor;
  38 import org.hibernate.internal.SessionFactoryRegistry;
  39 import org.hibernate.persister.entity.EntityPersister;
  40 import org.jboss.logging.Logger;
  41
  42 import eu.etaxonomy.cdm.api.application.CdmApplicationRemoteConfiguration;
  43 import eu.etaxonomy.cdm.model.common.CdmBase;
  44 import eu.etaxonomy.taxeditor.remoting.cache.ProxyUtils;
  45 import eu.etaxonomy.taxeditor.service.ICachedCommonService;
  46
  47 /**
  48  * Convenience base class for lazy initialization handlers.  Centralizes the basic plumbing of doing lazy
  49  * initialization freeing subclasses to acts as essentially adapters to their intended entity mode and/or
  50  * proxy generation strategy.
  51  *
  52  * @author Gavin King
  53  */
  54 public abstract class AbstractLazyInitializer implements LazyInitializer {
  55         private static final Logger log = Logger.getLogger( AbstractLazyInitializer.class );
  56
  57         private String entityName;
  58         private Serializable id;
  59         private Object target;
  60         private boolean initialized;
  61         private boolean readOnly;
  62         private boolean unwrap;
  63         private transient SessionImplementor session;
  64         private Boolean readOnlyBeforeAttachedToSession;
  65
  66         private String sessionFactoryUuid;
  67         private boolean specjLazyLoad = false;
  68
  69         /**
  70          * For serialization from the non-pojo initializers (HHH-3309)
  71          */
  72         protected AbstractLazyInitializer() {
  73         }
  74
  75         /**
  76          * Main constructor.
  77          *
  78          * @param entityName The name of the entity being proxied.
  79          * @param id The identifier of the entity being proxied.
  80          * @param session The session owning the proxy.
  81          */
  82         protected AbstractLazyInitializer(String entityName, Serializable id, SessionImplementor session) {
  83                 this.entityName = entityName;
  84                 this.id = id;
  85                 // initialize other fields depending on session state
  86                 if ( session == null ) {
  87                         unsetSession();
  88                 }
  89                 else {
  90                         setSession( session );
  91                 }
  92         }
  93
  94         @Override
  95         public final String getEntityName() {
  96                 return entityName;
  97         }
  98
  99         @Override
 100         public final Serializable getIdentifier() {
 101                 return id;
 102         }
 103
 104         @Override
 105         public final void setIdentifier(Serializable id) {
 106                 this.id = id;
 107         }
 108
 109         @Override
 110         public final boolean isUninitialized() {
 111                 return !initialized;
 112         }
 113
 114         @Override
 115         public final SessionImplementor getSession() {
 116                 return session;
 117         }
 118
 119         @Override
 120         public final void setSession(SessionImplementor s) throws HibernateException {
 121                 if ( s != session ) {
 122                         // check for s == null first, since it is least expensive
 123                         if ( s == null ) {
 124                                 unsetSession();
 125                         }
 126                         else if ( isConnectedToSession() ) {
 127                                 //TODO: perhaps this should be some other RuntimeException...
 128                                 throw new HibernateException( "illegally attempted to associate a proxy with two open Sessions" );
 129                         }
 130                         else {
 131                                 // s != null
 132                                 session = s;
 133                                 if ( readOnlyBeforeAttachedToSession == null ) {
 134                                         // use the default read-only/modifiable setting
 135                                         final EntityPersister persister = s.getFactory().getEntityPersister( entityName );
 136                                         setReadOnly( s.getPersistenceContext().isDefaultReadOnly() || !persister.isMutable() );
 137                                 }
 138                                 else {
 139                                         // use the read-only/modifiable setting indicated during deserialization
 140                                         setReadOnly( readOnlyBeforeAttachedToSession.booleanValue() );
 141                                         readOnlyBeforeAttachedToSession = null;
 142                                 }
 143                         }
 144                 }
 145         }
 146
 147         private static EntityKey generateEntityKeyOrNull(Serializable id, SessionImplementor s, String entityName) {
 148                 if ( id == null || s == null || entityName == null ) {
 149                         return null;
 150                 }
 151                 return s.generateEntityKey( id, s.getFactory().getEntityPersister( entityName ) );
 152         }
 153
 154         @Override
 155         public final void unsetSession() {
 156                 prepareForPossibleSpecialSpecjInitialization();
 157                 session = null;
 158                 readOnly = false;
 159                 readOnlyBeforeAttachedToSession = null;
 160         }
 161
 162         @Override
 163         public final void initialize() throws HibernateException {
 164                 // In remoting we are sure that session is null
 165                 // both when using property paths and switching off conversations
 166                 if(session == null && remoting) {
 167                         remoteInitialize();
 168                 }
 169                 if ( !initialized ) {
 170                         if ( specjLazyLoad ) {
 171                                 specialSpecjInitialization();
 172                         }
 173                         else if ( session == null ) {
 174                                 throw new LazyInitializationException( "could not initialize proxy - no Session" );
 175                         }
 176                         else if ( !session.isOpen() ) {
 177                                 throw new LazyInitializationException( "could not initialize proxy - the owning Session was closed" );
 178                         }
 179                         else if ( !session.isConnected() ) {
 180                                 throw new LazyInitializationException( "could not initialize proxy - the owning Session is disconnected" );
 181                         }
 182                         else {
 183                                 target = session.immediateLoad( entityName, id );
 184                                 initialized = true;
 185                                 checkTargetState();
 186                         }
 187                 }
 188                 else {
 189                         checkTargetState();
 190                 }
 191         }
 192
 193         protected void specialSpecjInitialization() {
 194                 if ( session == null ) {
 195                         //we have a detached collection thats set to null, reattach
 196                         if ( sessionFactoryUuid == null ) {
 197                                 throw new LazyInitializationException( "could not initialize proxy - no Session" );
 198                         }
 199                         try {
 200                                 SessionFactoryImplementor sf = (SessionFactoryImplementor)
 201                                                 SessionFactoryRegistry.INSTANCE.getSessionFactory( sessionFactoryUuid );
 202                                 SessionImplementor session = (SessionImplementor) sf.openSession();
 203
 204                                 // TODO: On the next major release, add an
 205                                 // 'isJTA' or 'getTransactionFactory' method to Session.
 206                                 boolean isJTA = session.getTransactionCoordinator()
 207                                                 .getTransactionContext().getTransactionEnvironment()
 208                                                 .getTransactionFactory()
 209                                                 .compatibleWithJtaSynchronization();
 210
 211                                 if ( !isJTA ) {
 212                                         // Explicitly handle the transactions only if we're not in
 213                                         // a JTA environment.  A lazy loading temporary session can
 214                                         // be created even if a current session and transaction are
 215                                         // open (ex: session.clear() was used).  We must prevent
 216                                         // multiple transactions.
 217                                         ( ( Session) session ).beginTransaction();
 218                                 }
 219
 220                                 try {
 221                                         target = session.immediateLoad( entityName, id );
 222                                 }
 223                                 finally {
 224                                         // make sure the just opened temp session gets closed!
 225                                         try {
 226                                                 if ( !isJTA ) {
 227                                                         ( ( Session) session ).getTransaction().commit();
 228                                                 }
 229                                                 ( (Session) session ).close();
 230                                         }
 231                                         catch (Exception e) {
 232                                                 log.warn( "Unable to close temporary session used to load lazy proxy associated to no session" );
 233                                         }
 234                                 }
 235                                 initialized = true;
 236                                 checkTargetState();
 237                         }
 238                         catch (Exception e) {
 239                                 e.printStackTrace();
 240                                 throw new LazyInitializationException( e.getMessage() );
 241                         }
 242                 }
 243                 else if ( session.isOpen() && session.isConnected() ) {
 244                         target = session.immediateLoad( entityName, id );
 245                         initialized = true;
 246                         checkTargetState();
 247                 }
 248                 else {
 249                         throw new LazyInitializationException( "could not initialize proxy - Session was closed or disced" );
 250                 }
 251         }
 252
 253         protected void prepareForPossibleSpecialSpecjInitialization() {
 254                 if ( session != null ) {
 255                         specjLazyLoad = session.getFactory().getSettings().isInitializeLazyStateOutsideTransactionsEnabled();
 256
 257                         if ( specjLazyLoad && sessionFactoryUuid == null ) {
 258                                 try {
 259                                         sessionFactoryUuid = (String) session.getFactory().getReference().get( "uuid" ).getContent();
 260                                 }
 261                                 catch (NamingException e) {
 262                                         //not much we can do if this fails...
 263                                 }
 264                         }
 265                 }
 266         }
 267
 268         private void checkTargetState() {
 269                 if ( !unwrap ) {
 270                         if ( target == null ) {
 271                                 getSession().getFactory().getEntityNotFoundDelegate().handleEntityNotFound( entityName, id );
 272                         }
 273                 }
 274         }
 275
 276         /**
 277          * Getter for property 'connectedToSession'.
 278          *
 279          * @return Value for property 'connectedToSession'.
 280          */
 281         protected final boolean isConnectedToSession() {
 282                 return getProxyOrNull() != null;
 283         }
 284
 285         private Object getProxyOrNull() {
 286                 final EntityKey entityKey = generateEntityKeyOrNull( getIdentifier(), session, getEntityName() );
 287                 if ( entityKey != null && session != null && session.isOpen() ) {
 288                         return session.getPersistenceContext().getProxy( entityKey );
 289                 }
 290                 return null;
 291         }
 292
 293         @Override
 294         public final Object getImplementation() {
 295                 initialize();
 296                 return target;
 297         }
 298
 299         @Override
 300         public final void setImplementation(Object target) {
 301                 this.target = target;
 302                 initialized = true;
 303         }
 304
 305         @Override
 306         public final Object getImplementation(SessionImplementor s) throws HibernateException {
 307                 final EntityKey entityKey = generateEntityKeyOrNull( getIdentifier(), s, getEntityName() );
 308                 return (entityKey == null ? null : s.getPersistenceContext().getEntity( entityKey ));
 309         }
 310
 311         /**
 312          * Getter for property 'target'.
 313          * <p/>
 314          * Same as {@link #getImplementation()} except that this method will not force initialization.
 315          *
 316          * @return Value for property 'target'.
 317          */
 318         protected final Object getTarget() {
 319                 return target;
 320         }
 321
 322         @Override
 323         public final boolean isReadOnlySettingAvailable() {
 324                 return (session != null && !session.isClosed());
 325         }
 326
 327         private void errorIfReadOnlySettingNotAvailable() {
 328                 if ( session == null ) {
 329                         throw new TransientObjectException(
 330                                         "Proxy is detached (i.e, session is null). The read-only/modifiable setting is only accessible when the proxy is associated with an open session."
 331                         );
 332                 }
 333                 if ( session.isClosed() ) {
 334                         throw new SessionException(
 335                                         "Session is closed. The read-only/modifiable setting is only accessible when the proxy is associated with an open session."
 336                         );
 337                 }
 338         }
 339
 340         @Override
 341         public final boolean isReadOnly() {
 342                 errorIfReadOnlySettingNotAvailable();
 343                 return readOnly;
 344         }
 345
 346         @Override
 347         public final void setReadOnly(boolean readOnly) {
 348                 errorIfReadOnlySettingNotAvailable();
 349                 // only update if readOnly is different from current setting
 350                 if ( this.readOnly != readOnly ) {
 351                         final EntityPersister persister = session.getFactory().getEntityPersister( entityName );
 352                         if ( !persister.isMutable() && !readOnly ) {
 353                                 throw new IllegalStateException( "cannot make proxies for immutable entities modifiable" );
 354                         }
 355                         this.readOnly = readOnly;
 356                         if ( initialized ) {
 357                                 EntityKey key = generateEntityKeyOrNull( getIdentifier(), session, getEntityName() );
 358                                 if ( key != null && session.getPersistenceContext().containsEntity( key ) ) {
 359                                         session.getPersistenceContext().setReadOnly( target, readOnly );
 360                                 }
 361                         }
 362                 }
 363         }
 364
 365         /**
 366          * Get the read-only/modifiable setting that should be put in affect when it is
 367          * attached to a session.
 368          * <p/>
 369          * This method should only be called during serialization when read-only/modifiable setting
 370          * is not available (i.e., isReadOnlySettingAvailable() == false)
 371          *
 372          * @return null, if the default setting should be used;
 373          *         true, for read-only;
 374          *         false, for modifiable
 375          *
 376          * @throws IllegalStateException if isReadOnlySettingAvailable() == true
 377          */
 378         protected final Boolean isReadOnlyBeforeAttachedToSession() {
 379                 if ( isReadOnlySettingAvailable() ) {
 380                         throw new IllegalStateException(
 381                                         "Cannot call isReadOnlyBeforeAttachedToSession when isReadOnlySettingAvailable == true"
 382                         );
 383                 }
 384                 return readOnlyBeforeAttachedToSession;
 385         }
 386
 387         /**
 388          * Set the read-only/modifiable setting that should be put in affect when it is
 389          * attached to a session.
 390          * <p/>
 391          * This method should only be called during deserialization, before associating
 392          * the proxy with a session.
 393          *
 394          * @param readOnlyBeforeAttachedToSession, the read-only/modifiable setting to use when
 395          * associated with a session; null indicates that the default should be used.
 396          *
 397          * @throws IllegalStateException if isReadOnlySettingAvailable() == true
 398          */
 399         /* package-private */
 400         final void setReadOnlyBeforeAttachedToSession(Boolean readOnlyBeforeAttachedToSession) {
 401                 if ( isReadOnlySettingAvailable() ) {
 402                         throw new IllegalStateException(
 403                                         "Cannot call setReadOnlyBeforeAttachedToSession when isReadOnlySettingAvailable == true"
 404                         );
 405                 }
 406                 this.readOnlyBeforeAttachedToSession = readOnlyBeforeAttachedToSession;
 407         }
 408
 409         @Override
 410         public boolean isUnwrap() {
 411                 return unwrap;
 412         }
 413
 414         @Override
 415         public void setUnwrap(boolean unwrap) {
 416                 this.unwrap = unwrap;
 417         }
 418
 419         /** Below is section of code which makes remote service calls */
 420
 421         private static CdmApplicationRemoteConfiguration configuration;
 422         private static boolean remoting = false;
 423
 424         public static void setConfiguration(CdmApplicationRemoteConfiguration conf) {
 425             remoting = true;
 426             configuration = conf;
 427         }
 428
 429
 430         private void remoteInitialize() {
 431
 432                 if(!initialized) {
 433                         int classid = ((Integer)getIdentifier()).intValue();
 434                         log.info("--> Remote Lazy Initializing Object " + getEntityName() + " with id " + classid);
 435                         Class clazz;
 436                         try {
 437                                 clazz = Class.forName(getEntityName());
 438                         } catch (ClassNotFoundException e) {
 439                                 throw new HibernateException("Class for " + getEntityName() + " not found", e);
 440                         }
 441                         if(configuration == null) {
 442                                 throw new HibernateException("CdmApplicationRemoteConfiguration not initialized (null)");
 443                         }
 444                         ICachedCommonService cachedCommonService = configuration.getCachedCommonService();
 445                         if(cachedCommonService == null) {
 446                                 throw new HibernateException("commonService not initialized (null)");
 447                         }
 448
 449                         CdmBase cdmBase = cachedCommonService.find(clazz,classid);
 450             if(ProxyUtils.isProxy(cdmBase)) {
 451                 throw new HibernateException("CdmBase Object initialized but is still a proxy");
 452             }
 453                         setImplementation(cdmBase);
 454
 455                 }
 456         }
 457
 458         public static boolean isInitialized(AbstractLazyInitializer obj) {
 459                 return obj.initialized;
 460         }
 461 }