//$Id: AbstractPersistentCollection.java 11301 2007-03-19 20:43:46Z steve.ebersole@jboss.com $
package org.hibernate.collection;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.ListIterator;
import org.hibernate.AssertionFailure;
import org.hibernate.HibernateException;
import org.hibernate.LazyInitializationException;
import org.hibernate.engine.CollectionEntry;
import org.hibernate.engine.ForeignKeys;
import org.hibernate.engine.SessionImplementor;
import org.hibernate.engine.TypedValue;
import org.hibernate.persister.collection.CollectionPersister;
import org.hibernate.pretty.MessageHelper;
import org.hibernate.type.Type;
import org.hibernate.util.CollectionHelper;
import org.hibernate.util.EmptyIterator;
import org.hibernate.util.MarkerObject;
/**
* Base class implementing <tt>PersistentCollection</tt>
* @see PersistentCollection
* @author Gavin King
*/
public abstract class AbstractPersistentCollection
implements Serializable, PersistentCollection {
private transient SessionImplementor session;
private boolean initialized;
private transient List operationQueue;
private transient boolean directlyAccessible;
private transient boolean initializing;
private Object owner;
private int cachedSize = -1;
private String role;
private Serializable key;
// collections detect changes made via their public interface and mark
// themselves as dirty as a performance optimization
private boolean dirty;
private Serializable storedSnapshot;
public final String getRole() {
return role;
}
public final Serializable getKey() {
return key;
}
public final boolean isUnreferenced() {
return role==null;
}
public final boolean isDirty() {
return dirty;
}
public final void clearDirty() {
dirty = false;
}
public final void dirty() {
dirty = true;
}
public final Serializable getStoredSnapshot() {
return storedSnapshot;
}
//Careful: these methods do not initialize the collection.
/**
* Is the initialized collection empty?
*/
public abstract boolean empty();
/**
* Called by any read-only method of the collection interface
*/
protected final void read() {
initialize(false);
}
/**
* Called by the <tt>size()</tt> method
*/
protected boolean readSize() {
if (!initialized) {
if ( cachedSize!=-1 && !hasQueuedOperations() ) {
return true;
}
else {
throwLazyInitializationExceptionIfNotConnected();
CollectionEntry entry = session.getPersistenceContext().getCollectionEntry(this);
CollectionPersister persister = entry.getLoadedPersister();
if ( persister.isExtraLazy() ) {
if ( hasQueuedOperations() ) {
session.flush();
}
cachedSize = persister.getSize( entry.getLoadedKey(), session );
return true;
}
}
}
read();
return false;
}
protected Boolean readIndexExistence(Object index) {
if (!initialized) {
throwLazyInitializationExceptionIfNotConnected();
CollectionEntry entry = session.getPersistenceContext().getCollectionEntry(this);
CollectionPersister persister = entry.getLoadedPersister();
if ( persister.isExtraLazy() ) {
if ( hasQueuedOperations() ) {
session.flush();
}
return new Boolean( persister.indexExists( entry.getLoadedKey(), index, session ) );
}
}
read();
return null;
}
protected Boolean readElementExistence(Object element) {
if (!initialized) {
throwLazyInitializationExceptionIfNotConnected();
CollectionEntry entry = session.getPersistenceContext().getCollectionEntry(this);
CollectionPersister persister = entry.getLoadedPersister();
if ( persister.isExtraLazy() ) {
if ( hasQueuedOperations() ) {
session.flush();
}
return new Boolean( persister.elementExists( entry.getLoadedKey(), element, session ) );
}
}
read();
return null;
}
protected static final Object UNKNOWN = new MarkerObject("UNKNOWN");
protected Object readElementByIndex(Object index) {
if (!initialized) {
throwLazyInitializationExceptionIfNotConnected();
CollectionEntry entry = session.getPersistenceContext().getCollectionEntry(this);
CollectionPersister persister = entry.getLoadedPersister();
if ( persister.isExtraLazy() ) {
if ( hasQueuedOperations() ) {
session.flush();
}
return persister.getElementByIndex( entry.getLoadedKey(), index, session, owner );
}
}
read();
return UNKNOWN;
}
protected int getCachedSize() {
return cachedSize;
}
/**
* Is the collection currently connected to an open session?
*/
private final boolean isConnectedToSession() {
return session!=null &&
session.isOpen() &&
session.getPersistenceContext().containsCollection(this);
}
/**
* Called by any writer method of the collection interface
*/
protected final void write() {
initialize(true);
dirty();
}
/**
* Is this collection in a state that would allow us to
* "queue" operations?
*/
protected boolean isOperationQueueEnabled() {
return !initialized &&
isConnectedToSession() &&
isInverseCollection();
}
/**
* Is this collection in a state that would allow us to
* "queue" puts? This is a special case, because of orphan
* delete.
*/
protected boolean isPutQueueEnabled() {
return !initialized &&
isConnectedToSession() &&
isInverseOneToManyOrNoOrphanDelete();
}
/**
* Is this collection in a state that would allow us to
* "queue" clear? This is a special case, because of orphan
* delete.
*/
protected boolean isClearQueueEnabled() {
return !initialized &&
isConnectedToSession() &&
isInverseCollectionNoOrphanDelete();
}
/**
* Is this the "inverse" end of a bidirectional association?
*/
private boolean isInverseCollection() {
CollectionEntry ce = session.getPersistenceContext().getCollectionEntry(this);
return ce != null && ce.getLoadedPersister().isInverse();
}
/**
* Is this the "inverse" end of a bidirectional association with
* no orphan delete enabled?
*/
private boolean isInverseCollectionNoOrphanDelete() {
CollectionEntry ce = session.getPersistenceContext().getCollectionEntry(this);
return ce != null &&
ce.getLoadedPersister().isInverse() &&
!ce.getLoadedPersister().hasOrphanDelete();
}
/**
* Is this the "inverse" end of a bidirectional one-to-many, or
* of a collection with no orphan delete?
*/
private boolean isInverseOneToManyOrNoOrphanDelete() {
CollectionEntry ce = session.getPersistenceContext().getCollectionEntry(this);
return ce != null && ce.getLoadedPersister().isInverse() && (
ce.getLoadedPersister().isOneToMany() ||
!ce.getLoadedPersister().hasOrphanDelete()
);
}
/**
* Queue an addition
*/
protected final void queueOperation(Object element) {
if (operationQueue==null) operationQueue = new ArrayList(10);
operationQueue.add(element);
dirty = true; //needed so that we remove this collection from the second-level cache
}
/**
* After reading all existing elements from the database,
* add the queued elements to the underlying collection.
*/
protected final void performQueuedOperations() {
for ( int i=0; i<operationQueue.size(); i++ ) {
( (DelayedOperation) operationQueue.get(i) ).operate();
}
}
/**
* After flushing, re-init snapshot state.
*/
public void setSnapshot(Serializable key, String role, Serializable snapshot) {
this.key = key;
this.role = role;
this.storedSnapshot = snapshot;
}
/**
* After flushing, clear any "queued" additions, since the
* database state is now synchronized with the memory state.
*/
public void postAction() {
operationQueue=null;
cachedSize = -1;
clearDirty();
}
/**
* Not called by Hibernate, but used by non-JDK serialization,
* eg. SOAP libraries.
*/
public AbstractPersistentCollection() {}
protected AbstractPersistentCollection(SessionImplementor session) {
this.session = session;
}
/**
* return the user-visible collection (or array) instance
*/
public Object getValue() {
return this;
}
/**
* Called just before reading any rows from the JDBC result set
*/
public void beginRead() {
// override on some subclasses
initializing = true;
}
/**
* Called after reading all rows from the JDBC result set
*/
public boolean endRead() {
//override on some subclasses
return afterInitialize();
}
public boolean afterInitialize() {
setInitialized();
//do this bit after setting initialized to true or it will recurse
if (operationQueue!=null) {
performQueuedOperations();
operationQueue=null;
cachedSize = -1;
return false;
}
else {
return true;
}
}
/**
* Initialize the collection, if possible, wrapping any exceptions
* in a runtime exception
* @param writing currently obsolete
* @throws LazyInitializationException if we cannot initialize
*/
protected final void initialize(boolean writing) {
if (!initialized) {
if (initializing) {
throw new LazyInitializationException("illegal access to loading collection");
}
throwLazyInitializationExceptionIfNotConnected();
session.initializeCollection(this, writing);
}
}
private void throwLazyInitializationExceptionIfNotConnected() {
if ( !isConnectedToSession() ) {
throwLazyInitializationException("no session or session was closed");
}
if ( !session.isConnected() ) {
throwLazyInitializationException("session is disconnected");
}
}
private void throwLazyInitializationException(String message) {
throw new LazyInitializationException(
"failed to lazily initialize a collection" +
( role==null ? "" : " of role: " + role ) +
", " + message
);
}
protected final void setInitialized() {
this.initializing = false;
this.initialized = true;
}
protected final void setDirectlyAccessible(boolean directlyAccessible) {
this.directlyAccessible = directlyAccessible;
}
/**
* Could the application possibly have a direct reference to
* the underlying collection implementation?
*/
public boolean isDirectlyAccessible() {
return directlyAccessible;
}
/**
* Disassociate this collection from the given session.
* @return true if this was currently associated with the given session
*/
public final boolean unsetSession(SessionImplementor currentSession) {
if (currentSession==this.session) {
this.session=null;
return true;
}
else {
return false;
}
}
/**
* Associate the collection with the given session.
* @return false if the collection was already associated with the session
* @throws HibernateException if the collection was already associated
* with another open session
*/
public final boolean setCurrentSession(SessionImplementor session) throws HibernateException {
if (session==this.session) {
return false;
}
else {
if ( isConnectedToSession() ) {
CollectionEntry ce = session.getPersistenceContext().getCollectionEntry(this);
if (ce==null) {
throw new HibernateException(
"Illegal attempt to associate a collection with two open sessions"
);
}
else {
throw new HibernateException(
"Illegal attempt to associate a collection with two open sessions: " +
MessageHelper.collectionInfoString(
ce.getLoadedPersister(),
ce.getLoadedKey(),
session.getFactory()
)
);
}
}
else {
this.session = session;
return true;
}
}
}
/**
* Do we need to completely recreate this collection when it changes?
*/
public boolean needsRecreate(CollectionPersister persister) {
return false;
}
/**
* To be called internally by the session, forcing
* immediate initialization.
*/
public final void forceInitialization() throws HibernateException {
if (!initialized) {
if (initializing) {
throw new AssertionFailure("force initialize loading collection");
}
if (session==null) {
throw new HibernateException("collection is not associated with any session");
}
if ( !session.isConnected() ) {
throw new HibernateException("disconnected session");
}
session.initializeCollection(this, false);
}
}
/**
* Get the current snapshot from the session
*/
protected final Serializable getSnapshot() {
return session.getPersistenceContext().getSnapshot(this);
}
/**
* Is this instance initialized?
*/
public final boolean wasInitialized() {
return initialized;
}
public boolean isRowUpdatePossible() {
return true;
}
/**
* Does this instance have any "queued" additions?
*/
public final boolean hasQueuedOperations() {
return operationQueue!=null;
}
/**
* Iterate the "queued" additions
*/
public final Iterator queuedAdditionIterator() {
if ( hasQueuedOperations() ) {
return new Iterator() {
int i = 0;
public Object next() {
return ( (DelayedOperation) operationQueue.get(i++) ).getAddedInstance();
}
public boolean hasNext() {
return i<operationQueue.size();
}
public void remove() {
throw new UnsupportedOperationException();
}
};
}
else {
return EmptyIterator.INSTANCE;
}
}
/**
* Iterate the "queued" additions
*/
public final Collection getQueuedOrphans(String entityName) {
if ( hasQueuedOperations() ) {
Collection additions = new ArrayList( operationQueue.size() );
Collection removals = new ArrayList( operationQueue.size() );
for ( int i = 0; i < operationQueue.size(); i++ ) {
DelayedOperation op = (DelayedOperation) operationQueue.get(i);
additions.add( op.getAddedInstance() );
removals.add( op.getOrphan() );
}
return getOrphans(removals, additions, entityName, session);
}
else {
return CollectionHelper.EMPTY_COLLECTION;
}
}
/**
* Called before inserting rows, to ensure that any surrogate keys
* are fully generated
*/
public void preInsert(CollectionPersister persister) throws HibernateException {}
/**
* Called after inserting a row, to fetch the natively generated id
*/
public void afterRowInsert(CollectionPersister persister, Object entry, int i) throws HibernateException {}
/**
* get all "orphaned" elements
*/
public abstract Collection getOrphans(Serializable snapshot, String entityName) throws HibernateException;
/**
* Get the current session
*/
public final SessionImplementor getSession() {
return session;
}
final class IteratorProxy implements Iterator {
private final Iterator iter;
IteratorProxy(Iterator iter) {
this.iter=iter;
}
public boolean hasNext() {
return iter.hasNext();
}
public Object next() {
return iter.next();
}
public void remove() {
write();
iter.remove();
}
}
final class ListIteratorProxy implements ListIterator {
private final ListIterator iter;
ListIteratorProxy(ListIterator iter) {
this.iter = iter;
}
public void add(Object o) {
write();
iter.add(o);
}
public boolean hasNext() {
return iter.hasNext();
}
public boolean hasPrevious() {
return iter.hasPrevious();
}
public Object next() {
return iter.next();
}
public int nextIndex() {
return iter.nextIndex();
}
public Object previous() {
return iter.previous();
}
public int previousIndex() {
return iter.previousIndex();
}
public void remove() {
write();
iter.remove();
}
public void set(Object o) {
write();
iter.set(o);
}
}
class SetProxy implements java.util.Set {
final Collection set;
SetProxy(Collection set) {
this.set=set;
}
public boolean add(Object o) {
write();
return set.add(o);
}
public boolean addAll(Collection c) {
write();
return set.addAll(c);
}
public void clear() {
write();
set.clear();
}
public boolean contains(Object o) {
return set.contains(o);
}
public boolean containsAll(Collection c) {
return set.containsAll(c);
}
public boolean isEmpty() {
return set.isEmpty();
}
public Iterator iterator() {
return new IteratorProxy( set.iterator() );
}
public boolean remove(Object o) {
write();
return set.remove(o);
}
public boolean removeAll(Collection c) {
write();
return set.removeAll(c);
}
public boolean retainAll(Collection c) {
write();
return set.retainAll(c);
}
public int size() {
return set.size();
}
public Object[] toArray() {
return set.toArray();
}
public Object[] toArray(Object[] array) {
return set.toArray(array);
}
}
final class ListProxy implements java.util.List {
private final java.util.List list;
ListProxy(java.util.List list) {
this.list = list;
}
public void add(int index, Object value) {
write();
list.add(index, value);
}
/**
* @see java.util.Collection#add(Object)
*/
public boolean add(Object o) {
write();
return list.add(o);
}
/**
* @see java.util.Collection#addAll(Collection)
*/
public boolean addAll(Collection c) {
write();
return list.addAll(c);
}
/**
* @see java.util.List#addAll(int, Collection)
*/
public boolean addAll(int i, Collection c) {
write();
return list.addAll(i, c);
}
/**
* @see java.util.Collection#clear()
*/
public void clear() {
write();
list.clear();
}
/**
* @see java.util.Collection#contains(Object)
*/
public boolean contains(Object o) {
return list.contains(o);
}
/**
* @see java.util.Collection#containsAll(Collection)
*/
public boolean containsAll(Collection c) {
return list.containsAll(c);
}
/**
* @see java.util.List#get(int)
*/
public Object get(int i) {
return list.get(i);
}
/**
* @see java.util.List#indexOf(Object)
*/
public int indexOf(Object o) {
return list.indexOf(o);
}
/**
* @see java.util.Collection#isEmpty()
*/
public boolean isEmpty() {
return list.isEmpty();
}
/**
* @see java.util.Collection#iterator()
*/
public Iterator iterator() {
return new IteratorProxy( list.iterator() );
}
/**
* @see java.util.List#lastIndexOf(Object)
*/
public int lastIndexOf(Object o) {
return list.lastIndexOf(o);
}
/**
* @see java.util.List#listIterator()
*/
public ListIterator listIterator() {
return new ListIteratorProxy( list.listIterator() );
}
/**
* @see java.util.List#listIterator(int)
*/
public ListIterator listIterator(int i) {
return new ListIteratorProxy( list.listIterator(i) );
}
/**
* @see java.util.List#remove(int)
*/
public Object remove(int i) {
write();
return list.remove(i);
}
/**
* @see java.util.Collection#remove(Object)
*/
public boolean remove(Object o) {
write();
return list.remove(o);
}
/**
* @see java.util.Collection#removeAll(Collection)
*/
public boolean removeAll(Collection c) {
write();
return list.removeAll(c);
}
/**
* @see java.util.Collection#retainAll(Collection)
*/
public boolean retainAll(Collection c) {
write();
return list.retainAll(c);
}
/**
* @see java.util.List#set(int, Object)
*/
public Object set(int i, Object o) {
write();
return list.set(i, o);
}
/**
* @see java.util.Collection#size()
*/
public int size() {
return list.size();
}
/**
* @see java.util.List#subList(int, int)
*/
public List subList(int i, int j) {
return list.subList(i, j);
}
/**
* @see java.util.Collection#toArray()
*/
public Object[] toArray() {
return list.toArray();
}
/**
* @see java.util.Collection#toArray(Object[])
*/
public Object[] toArray(Object[] array) {
return list.toArray(array);
}
}
protected interface DelayedOperation {
public void operate();
public Object getAddedInstance();
public Object getOrphan();
}
/**
* Given a collection of entity instances that used to
* belong to the collection, and a collection of instances
* that currently belong, return a collection of orphans
*/
protected static Collection getOrphans(
Collection oldElements,
Collection currentElements,
String entityName,
SessionImplementor session)
throws HibernateException {
// short-circuit(s)
if ( currentElements.size()==0 ) return oldElements; // no new elements, the old list contains only Orphans
if ( oldElements.size()==0) return oldElements; // no old elements, so no Orphans neither
Type idType = session.getFactory().getEntityPersister(entityName).getIdentifierType();
// create the collection holding the Orphans
Collection res = new ArrayList();
// collect EntityIdentifier(s) of the *current* elements - add them into a HashSet for fast access
java.util.Set currentIds = new HashSet();
for ( Iterator it=currentElements.iterator(); it.hasNext(); ) {
Object current = it.next();
if ( current!=null && ForeignKeys.isNotTransient(entityName, current, null, session) ) {
Serializable currentId = ForeignKeys.getEntityIdentifierIfNotUnsaved(entityName, current, session);
currentIds.add( new TypedValue( idType, currentId, session.getEntityMode() ) );
}
}
// iterate over the *old* list
for ( Iterator it=oldElements.iterator(); it.hasNext(); ) {
Object old = it.next();
Serializable oldId = ForeignKeys.getEntityIdentifierIfNotUnsaved(entityName, old, session);
if ( !currentIds.contains( new TypedValue( idType, oldId, session.getEntityMode() ) ) ) {
res.add(old);
}
}
return res;
}
static void identityRemove(
Collection list,
Object object,
String entityName,
SessionImplementor session)
throws HibernateException {
if ( object!=null && ForeignKeys.isNotTransient(entityName, object, null, session) ) {
Type idType = session.getFactory().getEntityPersister(entityName).getIdentifierType();
Serializable idOfCurrent = ForeignKeys.getEntityIdentifierIfNotUnsaved(entityName, object, session);
Iterator iter = list.iterator();
while ( iter.hasNext() ) {
Serializable idOfOld = ForeignKeys.getEntityIdentifierIfNotUnsaved(entityName, iter.next(), session);
if ( idType.isEqual( idOfCurrent, idOfOld, session.getEntityMode(), session.getFactory() ) ) {
iter.remove();
break;
}
}
}
}
public Object getIdentifier(Object entry, int i) {
throw new UnsupportedOperationException();
}
public Object getOwner() {
return owner;
}
public void setOwner(Object owner) {
this.owner = owner;
}
}
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