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/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* License: GNU Lesser General Public License (LGPL), version 2.1 or later.
* See the lgpl.txt file in the root directory or .
*/
package org.hibernate.proxy;
import java.io.Serializable;
import org.hibernate.FlushMode;
import org.hibernate.HibernateException;
import org.hibernate.LazyInitializationException;
import org.hibernate.SessionException;
import org.hibernate.TransientObjectException;
import org.hibernate.boot.spi.SessionFactoryOptions;
import org.hibernate.engine.spi.EntityKey;
import org.hibernate.engine.spi.PersistenceContext;
import org.hibernate.engine.spi.SessionFactoryImplementor;
import org.hibernate.engine.spi.SharedSessionContractImplementor;
import org.hibernate.internal.CoreLogging;
import org.hibernate.internal.CoreMessageLogger;
import org.hibernate.internal.SessionFactoryRegistry;
import org.hibernate.persister.entity.EntityPersister;
/**
* Convenience base class for lazy initialization handlers. Centralizes the basic plumbing of doing lazy
* initialization freeing subclasses to acts as essentially adapters to their intended entity mode and/or
* proxy generation strategy.
*
* @author Gavin King
*/
public abstract class AbstractLazyInitializer implements LazyInitializer {
private static final CoreMessageLogger LOG = CoreLogging.messageLogger( AbstractLazyInitializer.class );
private String entityName;
private Serializable id;
private Object target;
private boolean initialized;
private boolean readOnly;
private boolean unwrap;
private transient SharedSessionContractImplementor session;
private Boolean readOnlyBeforeAttachedToSession;
private String sessionFactoryUuid;
private boolean allowLoadOutsideTransaction;
/**
* @deprecated This constructor was initially intended for serialization only, and is not useful anymore.
* In any case it should not be relied on by user code.
* Subclasses should rather implement Serializable with an {@code Object writeReplace()} method returning
* a subclass of {@link AbstractSerializableProxy},
* which in turn implements Serializable and an {@code Object readResolve()} method
* instantiating the {@link AbstractLazyInitializer} subclass
* and calling {@link AbstractSerializableProxy#afterDeserialization(AbstractLazyInitializer)} on it.
* See {@link org.hibernate.proxy.pojo.bytebuddy.ByteBuddyInterceptor} and
* {@link org.hibernate.proxy.pojo.bytebuddy.SerializableProxy} for examples.
*/
@Deprecated
protected AbstractLazyInitializer() {
}
/**
* Main constructor.
*
* @param entityName The name of the entity being proxied.
* @param id The identifier of the entity being proxied.
* @param session The session owning the proxy.
*/
protected AbstractLazyInitializer(String entityName, Serializable id, SharedSessionContractImplementor session) {
this.entityName = entityName;
this.id = id;
// initialize other fields depending on session state
if ( session == null ) {
unsetSession();
}
else {
setSession( session );
}
}
@Override
public final String getEntityName() {
return entityName;
}
@Override
public final Serializable getIdentifier() {
if ( isUninitialized() && isInitializeProxyWhenAccessingIdentifier() ) {
initialize();
}
return id;
}
private boolean isInitializeProxyWhenAccessingIdentifier() {
return session != null && session.getFactory()
.getSessionFactoryOptions()
.getJpaCompliance().isJpaProxyComplianceEnabled();
}
@Override
public final void setIdentifier(Serializable id) {
this.id = id;
}
@Override
public final boolean isUninitialized() {
return !initialized;
}
@Override
public final SharedSessionContractImplementor getSession() {
return session;
}
@Override
public final void setSession(SharedSessionContractImplementor s) throws HibernateException {
if ( s != session ) {
// check for s == null first, since it is least expensive
if ( s == null ) {
unsetSession();
}
else if ( isConnectedToSession() ) {
//TODO: perhaps this should be some other RuntimeException...
LOG.attemptToAssociateProxyWithTwoOpenSessions(
entityName,
id
);
throw new HibernateException( "illegally attempted to associate proxy [" + entityName + "#" + id + "] with two open Sessions" );
}
else {
// s != null
session = s;
if ( readOnlyBeforeAttachedToSession == null ) {
// use the default read-only/modifiable setting
final EntityPersister persister = s.getFactory().getEntityPersister( entityName );
setReadOnly( s.getPersistenceContext().isDefaultReadOnly() || !persister.isMutable() );
}
else {
// use the read-only/modifiable setting indicated during deserialization
setReadOnly( readOnlyBeforeAttachedToSession );
readOnlyBeforeAttachedToSession = null;
}
}
}
}
private static EntityKey generateEntityKeyOrNull(Serializable id, SharedSessionContractImplementor s, String entityName) {
if ( id == null || s == null || entityName == null ) {
return null;
}
return s.generateEntityKey( id, s.getFactory().getEntityPersister( entityName ) );
}
@Override
public final void unsetSession() {
prepareForPossibleLoadingOutsideTransaction();
session = null;
readOnly = false;
readOnlyBeforeAttachedToSession = null;
}
@Override
public final void initialize() throws HibernateException {
if ( !initialized ) {
if ( allowLoadOutsideTransaction ) {
permissiveInitialization();
}
else if ( session == null ) {
throw new LazyInitializationException( "could not initialize proxy [" + entityName + "#" + id + "] - no Session" );
}
else if ( !session.isOpenOrWaitingForAutoClose() ) {
throw new LazyInitializationException( "could not initialize proxy [" + entityName + "#" + id + "] - the owning Session was closed" );
}
else if ( !session.isConnected() ) {
throw new LazyInitializationException( "could not initialize proxy [" + entityName + "#" + id + "] - the owning Session is disconnected" );
}
else {
target = session.immediateLoad( entityName, id );
initialized = true;
checkTargetState(session);
}
}
else {
checkTargetState(session);
}
}
protected void permissiveInitialization() {
if ( session == null ) {
//we have a detached collection thats set to null, reattach
if ( sessionFactoryUuid == null ) {
throw new LazyInitializationException( "could not initialize proxy [" + entityName + "#" + id + "] - no Session" );
}
try {
SessionFactoryImplementor sf = (SessionFactoryImplementor)
SessionFactoryRegistry.INSTANCE.getSessionFactory( sessionFactoryUuid );
SharedSessionContractImplementor session = (SharedSessionContractImplementor) sf.openSession();
session.getPersistenceContext().setDefaultReadOnly( true );
session.setFlushMode( FlushMode.MANUAL );
boolean isJTA = session.getTransactionCoordinator().getTransactionCoordinatorBuilder().isJta();
if ( !isJTA ) {
// Explicitly handle the transactions only if we're not in
// a JTA environment. A lazy loading temporary session can
// be created even if a current session and transaction are
// open (ex: session.clear() was used). We must prevent
// multiple transactions.
session.beginTransaction();
}
try {
target = session.immediateLoad( entityName, id );
initialized = true;
checkTargetState(session);
}
finally {
// make sure the just opened temp session gets closed!
try {
if ( !isJTA ) {
session.getTransaction().commit();
}
session.close();
}
catch (Exception e) {
LOG.warn( "Unable to close temporary session used to load lazy proxy associated to no session" );
}
}
}
catch (Exception e) {
LOG.error( "Initialization failure [" + entityName + "#" + id + "]", e );
throw new LazyInitializationException( e.getMessage() );
}
}
else if ( session.isOpenOrWaitingForAutoClose() && session.isConnected() ) {
target = session.immediateLoad( entityName, id );
initialized = true;
checkTargetState(session);
}
else {
throw new LazyInitializationException( "could not initialize proxy [" + entityName + "#" + id + "] - Session was closed or disced" );
}
}
/**
* Attempt to initialize the proxy without loading anything from the database.
*
* This will only have any effect if the proxy is still attached to a session,
* and the entity being proxied has been loaded and added to the persistence context
* of that session since the proxy was created.
*/
public final void initializeWithoutLoadIfPossible() {
if ( !initialized && session != null && session.isOpenOrWaitingForAutoClose() ) {
final EntityKey key = session.generateEntityKey(
getIdentifier(),
session.getFactory().getMetamodel().entityPersister( getEntityName() )
);
final Object entity = session.getPersistenceContextInternal().getEntity( key );
if ( entity != null ) {
setImplementation( entity );
}
}
}
/**
* Initialize internal state based on the currently attached session,
* in order to be ready to load data even after the proxy is detached from the session.
*
* This method only has any effect if
* {@link SessionFactoryOptions#isInitializeLazyStateOutsideTransactionsEnabled()} is {@code true}.
*/
protected void prepareForPossibleLoadingOutsideTransaction() {
if ( session != null ) {
allowLoadOutsideTransaction = session.getFactory().getSessionFactoryOptions().isInitializeLazyStateOutsideTransactionsEnabled();
if ( allowLoadOutsideTransaction && sessionFactoryUuid == null ) {
sessionFactoryUuid = session.getFactory().getUuid();
}
}
}
private void checkTargetState(SharedSessionContractImplementor session) {
if ( !unwrap ) {
if ( target == null ) {
session.getFactory().getEntityNotFoundDelegate().handleEntityNotFound( entityName, id );
}
}
}
/**
* Getter for property 'connectedToSession'.
*
* @return Value for property 'connectedToSession'.
*/
protected final boolean isConnectedToSession() {
return getProxyOrNull() != null;
}
private Object getProxyOrNull() {
final EntityKey entityKey = generateEntityKeyOrNull( getIdentifier(), session, getEntityName() );
if ( entityKey != null && session != null && session.isOpenOrWaitingForAutoClose() ) {
return session.getPersistenceContextInternal().getProxy( entityKey );
}
return null;
}
@Override
public final Object getImplementation() {
initialize();
return target;
}
@Override
public final void setImplementation(Object target) {
this.target = target;
initialized = true;
}
@Override
public final Object getImplementation(SharedSessionContractImplementor s) throws HibernateException {
final EntityKey entityKey = generateEntityKeyOrNull( getIdentifier(), s, getEntityName() );
return ( entityKey == null ? null : s.getPersistenceContext().getEntity( entityKey ) );
}
/**
* Getter for property 'target'.
*
* Same as {@link #getImplementation()} except that this method will not force initialization.
*
* @return Value for property 'target'.
*/
protected final Object getTarget() {
return target;
}
@Override
public final boolean isReadOnlySettingAvailable() {
return (session != null && !session.isClosed());
}
private void errorIfReadOnlySettingNotAvailable() {
if ( session == null ) {
throw new TransientObjectException(
"Proxy [" + entityName + "#" + id + "] is detached (i.e, session is null). The read-only/modifiable setting is only accessible when the proxy is associated with an open session."
);
}
if ( !session.isOpenOrWaitingForAutoClose() ) {
throw new SessionException(
"Session is closed. The read-only/modifiable setting is only accessible when the proxy [" + entityName + "#" + id + "] is associated with an open session."
);
}
}
@Override
public final boolean isReadOnly() {
errorIfReadOnlySettingNotAvailable();
return readOnly;
}
@Override
public final void setReadOnly(boolean readOnly) {
errorIfReadOnlySettingNotAvailable();
// only update if readOnly is different from current setting
if ( this.readOnly != readOnly ) {
final EntityPersister persister = session.getFactory().getEntityPersister( entityName );
if ( !persister.isMutable() && !readOnly ) {
throw new IllegalStateException( "cannot make proxies [" + entityName + "#" + id + "] for immutable entities modifiable" );
}
this.readOnly = readOnly;
if ( initialized ) {
EntityKey key = generateEntityKeyOrNull( getIdentifier(), session, getEntityName() );
final PersistenceContext persistenceContext = session.getPersistenceContext();
if ( key != null && persistenceContext.containsEntity( key ) ) {
persistenceContext.setReadOnly( target, readOnly );
}
}
}
}
/**
* Get the read-only/modifiable setting that should be put in affect when it is
* attached to a session.
*
* This method should only be called during serialization when read-only/modifiable setting
* is not available (i.e., isReadOnlySettingAvailable() == false)
*
* @return null, if the default setting should be used;
* true, for read-only;
* false, for modifiable
*
* @throws IllegalStateException if isReadOnlySettingAvailable() == true
*/
public final Boolean isReadOnlyBeforeAttachedToSession() {
if ( isReadOnlySettingAvailable() ) {
throw new IllegalStateException(
"Cannot call isReadOnlyBeforeAttachedToSession when isReadOnlySettingAvailable == true [" + entityName + "#" + id + "]"
);
}
return readOnlyBeforeAttachedToSession;
}
/**
* Get whether the proxy can load data even
* if it's not attached to a session with an ongoing transaction.
*
* This method should only be called during serialization,
* and only makes sense after a call to {@link #prepareForPossibleLoadingOutsideTransaction()}.
*
* @return {@code true} if out-of-transaction loads are allowed, {@code false} otherwise.
*/
protected boolean isAllowLoadOutsideTransaction() {
return allowLoadOutsideTransaction;
}
/**
* Get the session factory UUID.
*
* This method should only be called during serialization,
* and only makes sense after a call to {@link #prepareForPossibleLoadingOutsideTransaction()}.
*
* @return the session factory UUID.
*/
protected String getSessionFactoryUuid() {
return sessionFactoryUuid;
}
/**
* Restore settings that are not passed to the constructor,
* but are still preserved during serialization.
*
* This method should only be called during deserialization, before associating
* the proxy with a session.
*
* @param readOnlyBeforeAttachedToSession the read-only/modifiable setting to use when
* associated with a session; null indicates that the default should be used.
* @param sessionFactoryUuid the session factory uuid, to be used if {@code allowLoadOutsideTransaction} is {@code true}.
* @param allowLoadOutsideTransaction whether the proxy can load data even
* if it's not attached to a session with an ongoing transaction.
*
* @throws IllegalStateException if isReadOnlySettingAvailable() == true
*/
/* package-private */
final void afterDeserialization(Boolean readOnlyBeforeAttachedToSession,
String sessionFactoryUuid, boolean allowLoadOutsideTransaction) {
if ( isReadOnlySettingAvailable() ) {
throw new IllegalStateException(
"Cannot call afterDeserialization when isReadOnlySettingAvailable == true [" + entityName + "#" + id + "]"
);
}
this.readOnlyBeforeAttachedToSession = readOnlyBeforeAttachedToSession;
this.sessionFactoryUuid = sessionFactoryUuid;
this.allowLoadOutsideTransaction = allowLoadOutsideTransaction;
}
@Override
public boolean isUnwrap() {
return unwrap;
}
@Override
public void setUnwrap(boolean unwrap) {
this.unwrap = unwrap;
}
}