/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.openjpa.util;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.ListIterator;
import org.apache.openjpa.kernel.Broker;
import org.apache.openjpa.kernel.BrokerImpl;
import org.apache.openjpa.kernel.DetachedValueStateManager;
import org.apache.openjpa.kernel.OpenJPAStateManager;
import org.apache.openjpa.kernel.StateManagerImpl;
/**
* Utility methods used by collection proxies.
*
* @author Abe White
* @nojavadoc
*/
public class ProxyCollections
extends Proxies {
/**
* Call before invoking {@link List#add(int,Object)} on super.
*/
public static void beforeAdd(ProxyCollection coll, int index, Object value){
assertAllowedType(value, coll.getElementType());
dirty(coll, true);
}
/**
* Call before invoking {@link Vector#insertElementAt(Object,int)} on super.
*/
public static void beforeInsertElementAt(ProxyCollection coll, Object value,
int index) {
beforeAdd(coll, index, value);
}
/**
* Call before invoking {@link Collection#add(Object)} on super.
*/
public static void beforeAdd(ProxyCollection coll, Object value) {
assertAllowedType(value, coll.getElementType());
// Must only dirty the collection outside of a delayed load
if (!isDirectAccess(coll)) {
dirty(coll, false);
}
}
/**
* Call after invoking {@link Collection#add(Object)} on super.
*
* @param added whether the object was added
* @return <code>added</code>, for convenience
*/
public static boolean afterAdd(ProxyCollection coll, Object value,
boolean added) {
if (!isDirectAccess(coll) && added && coll.getChangeTracker() != null) {
setDirectAccess(coll,true);
((CollectionChangeTracker) coll.getChangeTracker()).added(value);
setDirectAccess(coll,false);
}
return added;
}
/**
* Call before invoking {@link Vector#addElement(Object)} on super.
*/
public static void beforeAddElement(ProxyCollection coll, Object value) {
beforeAdd(coll, value);
}
/**
* Call after invoking {@link Vector#addElement(Object)} on super.
*/
public static void afterAddElement(ProxyCollection coll, Object value) {
afterAdd(coll, value, true);
}
/**
* Call before invoking {@link LinkedList#addFirst(Object)} on super.
*/
public static void beforeAddFirst(ProxyCollection coll, Object value) {
beforeAdd(coll, 0, value);
}
/**
* Call before invoking {@link LinkedList#addLast(Object)} on super.
*/
public static void beforeAddLast(ProxyCollection coll, Object value) {
beforeAdd(coll, value);
}
/**
* Call after invoking {@link LinkedList#addLast(Object)} on super.
*/
public static void afterAddLast(ProxyCollection coll, Object value) {
afterAdd(coll, value, true);
}
/**
* Call before invoking {@link Queue#offer(Object)} on super.
*/
public static void beforeOffer(ProxyCollection coll, Object value) {
beforeAdd(coll, value);
}
/**
* Call after invoking {@link Queue#offer(Object)} on super.
*
* @param added whether the object was added
* @return <code>added</code>, for convenience
*/
public static boolean afterOffer(ProxyCollection coll, Object value,
boolean added) {
return afterAdd(coll, value, added);
}
/**
* Override for {@link List#addAll(int, Collection)}.
*/
public static boolean addAll(ProxyCollection coll, int index,
Collection values) {
List list = (List) coll;
for (Iterator itr = values.iterator(); itr.hasNext(); index++)
list.add(index, itr.next());
return values.size() > 0;
}
/**
* Override for {@link Collection#addAll}.
*/
public static boolean addAll(ProxyCollection coll, Collection values) {
boolean added = false;
for (Iterator<?> itr = values.iterator(); itr.hasNext();)
added |= coll.add(itr.next());
return added;
}
/**
* Call before clearing collection.
*/
public static void beforeClear(ProxyCollection coll) {
dirty(coll, true);
for (Iterator<?> itr = coll.iterator(); itr.hasNext();)
removed(coll, itr.next(), false);
}
/**
* Call before clearing vector.
*/
public static void beforeRemoveAllElements(ProxyCollection coll) {
beforeClear(coll);
}
/**
* Wrap given iterator in a proxy.
*/
public static Iterator afterIterator(final ProxyCollection coll,
final Iterator itr) {
// check for proxied; some coll impls delegate iterator methods
if (itr instanceof ProxyIterator)
return itr;
return new ProxyIterator() {
private Object _last = null;
public boolean hasNext() {
return itr.hasNext();
}
public Object next() {
_last = itr.next();
return _last;
}
public void remove() {
dirty(coll, false);
itr.remove();
if (coll.getChangeTracker() != null)
((CollectionChangeTracker) coll.getChangeTracker()).
removed(_last);
Proxies.removed(coll, _last, false);
}
};
}
/**
* Wrap given iterator in a proxy.
*/
public static ListIterator afterListIterator(final ProxyCollection coll,
int idx, final ListIterator itr) {
return afterListIterator(coll, itr);
}
/**
* Wrap given iterator in a proxy.
*/
public static ListIterator afterListIterator(final ProxyCollection coll,
final ListIterator itr) {
// check for proxied; some coll impls delegate iterator methods
if (itr instanceof ProxyListIterator)
return itr;
return new ProxyListIterator() {
private Object _last = null;
public boolean hasNext() {
return itr.hasNext();
}
public int nextIndex() {
return itr.nextIndex();
}
public Object next() {
_last = itr.next();
return _last;
}
public boolean hasPrevious() {
return itr.hasPrevious();
}
public int previousIndex() {
return itr.previousIndex();
}
public Object previous() {
_last = itr.previous();
return _last;
}
public void set(Object o) {
assertAllowedType(o, coll.getElementType());
dirty(coll, false);
itr.set(o);
if (coll.getChangeTracker() != null)
coll.getChangeTracker().stopTracking();
Proxies.removed(coll, _last, false);
_last = o;
}
public void add(Object o) {
assertAllowedType(o, coll.getElementType());
dirty(coll, false);
itr.add(o);
if (coll.getChangeTracker() != null) {
if (hasNext())
coll.getChangeTracker().stopTracking();
else
((CollectionChangeTracker) coll.getChangeTracker()).
added(o);
}
_last = o;
}
public void remove() {
dirty(coll, false);
itr.remove();
if (coll.getChangeTracker() != null)
((CollectionChangeTracker) coll.getChangeTracker()).
removed(_last);
Proxies.removed(coll, _last, false);
}
};
}
/**
* Call before invoking {@link List#remove(int)} on super.
*/
public static void beforeRemove(ProxyCollection coll, int index) {
dirty(coll, false);
}
/**
* Call after invoking {@link List#remove(int)} on super.
*
* @param removed the removed object
* @return the removed object, for convenience
*/
public static Object afterRemove(ProxyCollection coll, int index,
Object removed) {
if (coll.getChangeTracker() != null)
((CollectionChangeTracker) coll.getChangeTracker()).
removed(removed);
removed(coll, removed, false);
return removed;
}
/**
* Call before invoking {@link Vector#removeElementAt(int)} on super.
*/
public static void beforeRemoveElementAt(ProxyCollection coll, int index) {
beforeRemove(coll, index);
}
/**
* Call before invoking {@link Collection#remove} on super.
*/
public static void beforeRemove(ProxyCollection coll, Object o) {
// Must only dirty the collection outside of a delayed load
if (!isDirectAccess(coll)) {
dirty(coll, false);
}
}
/**
* Call after invoking {@link Collection#remove} on super.
*
* @param removed whether the object was removed
* @return whether the object was removed, for convenience
*/
public static boolean afterRemove(ProxyCollection coll, Object o,
boolean removed){
boolean isDelayed = isDelayed(coll);
boolean direct = isDirectAccess(coll);
if (!isDelayed) {
if (!removed)
return false;
}
if (!direct && coll.getChangeTracker() != null) {
// switch on direct access to prevent the removed op from
// inadvertently loading the collection
setDirectAccess(coll, true);
((CollectionChangeTracker) coll.getChangeTracker()).removed(o);
setDirectAccess(coll, false);
}
if (!isDelayed) {
removed(coll, o, false);
}
return true;
}
private static boolean isDirectAccess(ProxyCollection coll) {
if (coll instanceof DelayedProxy) {
DelayedProxy dpxy = (DelayedProxy)coll;
return dpxy.isDirectAccess();
}
return false;
}
private static void setDirectAccess(ProxyCollection coll, boolean direct) {
if (coll instanceof DelayedProxy) {
DelayedProxy dpxy = (DelayedProxy)coll;
dpxy.setDirectAccess(direct);
}
}
/**
* Call before invoking {@link Vector#removeElement} on super.
*/
public static void beforeRemoveElement(ProxyCollection coll, Object o) {
beforeRemove(coll, o);
}
/**
* Call after invoking {@link Vector#removeElement} on super.
*/
public static boolean afterRemoveElement(ProxyCollection coll, Object o,
boolean removed) {
return afterRemove(coll, o, removed);
}
/**
* Call before invoking {@link LinkedList#removeFirst} on super.
*/
public static void beforeRemoveFirst(ProxyCollection coll) {
beforeRemove(coll, 0);
}
/**
* Call after invoking {@link LinkedList#removeFirst} on super.
*/
public static Object afterRemoveFirst(ProxyCollection coll, Object removed){
return afterRemove(coll, 0, removed);
}
/**
* Call after invoking {@link LinkedList#removeLast} on super.
*/
public static void beforeRemoveLast(ProxyCollection coll) {
beforeRemove(coll, coll.size() - 1);
}
/**
* Call after invoking {@link LinkedList#removeLast} on super.
*/
public static Object afterRemoveLast(ProxyCollection coll, Object removed) {
return afterRemove(coll, coll.size(), removed);
}
/**
* Call before invoking {@link Queue#remove} on super.
*/
public static void beforeRemove(ProxyCollection coll) {
beforeRemove(coll, 0);
}
/**
* Call after invoking {@link Queue#remove} on super.
*/
public static Object afterRemove(ProxyCollection coll, Object removed){
return afterRemove(coll, 0, removed);
}
/**
* Call before invoking {@link Queue#poll} on super.
*/
public static void beforePoll(ProxyCollection coll) {
if (!coll.isEmpty())
beforeRemove(coll, 0);
}
/**
* Call after invoking {@link Queue#poll} on super.
*/
public static Object afterPoll(ProxyCollection coll, Object removed) {
if (removed != null)
afterRemove(coll, 0, removed);
return removed;
}
/**
* Override for {@link Collection#removeAll}.
*/
public static boolean removeAll(ProxyCollection coll, Collection<?> vals) {
boolean removed = false;
for (Iterator<?> itr = vals.iterator(); itr.hasNext();)
removed |= coll.remove(itr.next());
return removed;
}
/**
* Override for {@link Collection#retainAll}.
*/
public static boolean retainAll(ProxyCollection coll, Collection<?> vals) {
int size = coll.size();
for (Iterator<?> itr = coll.iterator(); itr.hasNext();)
if (!vals.contains(itr.next()))
itr.remove();
return coll.size() < size;
}
/**
* Call before invoking {@link List#set} on super.
*/
public static void beforeSet(ProxyCollection coll, int index,
Object element) {
assertAllowedType(element, coll.getElementType());
dirty(coll, true);
}
/**
* Call after invoking {@link List#set} on super.
*
* @param replaced the replaced object
* @return the replaced object, for convenience
*/
public static Object afterSet(ProxyCollection coll, int index,
Object element, Object replaced) {
if (replaced != element)
removed(coll, replaced, false);
return replaced;
}
/**
* Call before invoking {@link Vector#setElementAt} on super.
*/
public static void beforeSetElementAt(ProxyCollection coll, Object element,
int index) {
beforeSet(coll, index, element);
}
/**
* Call after invoking {@link Vector#setElementAt} on super.
*/
public static Object afterSetElementAt(ProxyCollection coll, Object element,
int index, Object replaced) {
return afterSet(coll, index, element, replaced);
}
/**
* Marker interface for a proxied iterator.
*/
public static interface ProxyIterator
extends Iterator {
}
/**
* Marker interface for a proxied list iterator.
*/
public static interface ProxyListIterator
extends ProxyIterator, ListIterator {
}
public static void loadCollection(ProxyCollection proxy) {
loadCollection(proxy, false);
}
public static void loadCollection(ProxyCollection proxy, boolean detaching) {
if (!isDelayed(proxy)) {
return;
}
DelayedProxy dProxy = (DelayedProxy)proxy;
if (dProxy.isDirectAccess()) {
return;
}
boolean state[] = new boolean[2];
try {
dProxy.setDirectAccess(true);
state = checkState(proxy);
boolean tracking = false;
ChangeTracker ct = proxy.getChangeTracker();
Collection<?> added = null;
Collection<?> removed = null;
if (ct != null && ct.isTracking() ) {
if (!ct.getAdded().isEmpty()) {
added = new ArrayList(ct.getAdded());
}
if (!ct.getRemoved().isEmpty()) {
removed = new ArrayList(ct.getRemoved());
}
tracking = true;
ct.stopTracking();
}
if (proxy.size() > 0) {
proxy.clear();
}
dProxy.getDelayedOwner().loadDelayedField(dProxy.getDelayedField());
if (!detaching && tracking && !ct.isTracking()) {
ct.startTracking();
}
// add new elements
if (added != null && added.size() > 0) {
dProxy.setDirectAccess(false);
proxy.addAll(added);
added.clear();
}
// purge removed elements
if (removed != null && removed.size() > 0) {
dProxy.setDirectAccess(false);
proxy.removeAll(removed);
removed.clear();
}
} finally {
dProxy.setDirectAccess(false);
if (state[0]) {
dProxy.closeBroker();
}
if (state[1]) {
clearStateManager(proxy);
}
}
}
public static boolean isDelayed(ProxyCollection proxy) {
if (proxy instanceof DelayedProxy) {
DelayedProxy dProxy = (DelayedProxy)proxy;
OpenJPAStateManager sm = dProxy.getDelayedOwner();
return (sm != null &&
sm.isDelayed(dProxy.getDelayedField()));
}
return false;
}
private static boolean[] checkState(ProxyCollection proxy) {
boolean[] state = new boolean[2];
DelayedProxy dProxy = (DelayedProxy)proxy;
OpenJPAStateManager sm = dProxy.getDelayedOwner();
if (sm != null) {
// If the broker assigned to this proxy is null, closed or no longer
// manages the pc, produce a new one
Broker broker = sm.getContext().getBroker();
if (dProxy.isDetached() || broker == null || broker.isClosed()
|| (!broker.isClosed() && !broker.isPersistent(sm.getPersistenceCapable()))) {
state[0] = true;
broker = dProxy.getBroker();
((StateManagerImpl)sm).setBroker((BrokerImpl)broker);
}
if (dProxy.isDetached() || sm.getPersistenceCapable().pcGetStateManager() == null) {
state[1] = true;
if (dProxy.getOwnerStateManager() != null) {
sm.getPersistenceCapable().pcReplaceStateManager(dProxy.getOwnerStateManager());
((StateManagerImpl)dProxy.getOwnerStateManager()).setBroker((BrokerImpl)broker);
} else {
sm.getPersistenceCapable().pcReplaceStateManager(
new DetachedValueStateManager(sm.getPersistenceCapable(), sm.getContext()));
}
}
}
return state;
}
private static void clearStateManager(ProxyCollection proxy) {
OpenJPAStateManager sm = proxy.getOwner();
if (sm != null) {
sm.getPersistenceCapable().pcReplaceStateManager(null);
}
}
}