/*
* JBoss, Home of Professional Open Source
* Copyright 2011 Red Hat Inc. and/or its affiliates and other
* contributors as indicated by the @author tags. All rights reserved.
* See the copyright.txt in the distribution for a full listing of
* individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.infinispan.container.entries;
import org.infinispan.atomic.AtomicHashMap;
import org.infinispan.atomic.Delta;
import org.infinispan.atomic.DeltaAware;
import org.infinispan.container.DataContainer;
import org.infinispan.container.versioning.EntryVersion;
import org.infinispan.util.Util;
import org.infinispan.util.logging.Log;
import org.infinispan.util.logging.LogFactory;
import java.util.LinkedList;
import java.util.List;
import static org.infinispan.container.entries.DeltaAwareCacheEntry.Flags.*;
/**
* A wrapper around a cached entry that encapsulates DeltaAware and Delta semantics when writes are
* initiated, committed or rolled back.
*
* @author Manik Surtani (<a href="mailto:manik@jboss.org">manik@jboss.org</a>)
* @since 5.1
*/
public class DeltaAwareCacheEntry implements CacheEntry, StateChangingEntry {
private static final Log log = LogFactory.getLog(DeltaAwareCacheEntry.class);
private static final boolean trace = log.isTraceEnabled();
protected Object key;
protected CacheEntry wrappedEntry;
protected DeltaAware value, oldValue;
protected final List<Delta> deltas;
protected byte flags = 0;
// add Map representing uncommitted changes
protected AtomicHashMap<?, ?> uncommittedChanges;
public DeltaAwareCacheEntry(Object key, DeltaAware value, CacheEntry wrappedEntry) {
setValid(true);
this.key = key;
this.value = value;
this.wrappedEntry = wrappedEntry;
this.uncommittedChanges = new AtomicHashMap();
this.deltas = new LinkedList<Delta>();
}
@Override
public byte getStateFlags() {
return flags;
}
@Override
public void copyStateFlagsFrom(StateChangingEntry other) {
this.flags = other.getStateFlags();
}
public void appendDelta(Delta d) {
deltas.add(d);
d.merge(uncommittedChanges);
setChanged();
}
public AtomicHashMap<?, ?> getUncommittedChages() {
return uncommittedChanges;
}
protected static enum Flags {
CHANGED(1), // same as 1 << 0
CREATED(1 << 1), REMOVED(1 << 2), VALID(1 << 3), LOCK_PLACEHOLDER(1 << 4), EVICTED(1 << 5);
final byte mask;
Flags(int mask) {
this.mask = (byte) mask;
}
}
/**
* Tests whether a flag is set.
*
* @param flag
* flag to test
* @return true if set, false otherwise.
*/
protected final boolean isFlagSet(Flags flag) {
return (flags & flag.mask) != 0;
}
/**
* Utility method that sets the value of the given flag to true.
*
* @param flag
* flag to set
*/
protected final void setFlag(Flags flag) {
flags |= flag.mask;
}
/**
* Utility method that sets the value of the flag to false.
*
* @param flag
* flag to unset
*/
protected final void unsetFlag(Flags flag) {
flags &= ~flag.mask;
}
@Override
public final long getLifespan() {
return 0;
}
@Override
public final long getMaxIdle() {
return 0;
}
@Override
public final void setMaxIdle(long maxIdle) {
// irrelevant
}
@Override
public final void setLifespan(long lifespan) {
// irrelevant
}
@Override
public final Object getKey() {
return key;
}
@Override
public final Object getValue() {
return value;
}
@Override
public final Object setValue(Object value) {
Object oldValue = this.value;
this.value = (DeltaAware) value;
return oldValue;
}
@Override
public boolean isNull() {
return false;
}
public void copyForUpdate(DataContainer container, boolean writeSkewCheck) {
if (isChanged())
return; // already copied
setChanged(); // mark as changed
// if newly created, then nothing to copy.
if (!isCreated())
oldValue = value;
}
@Override
public final void commit(DataContainer container, EntryVersion version) {
// only do stuff if there are changes.
if (wrappedEntry != null) {
wrappedEntry.commit(container, version);
}
if (value != null && !deltas.isEmpty()) {
for (Delta delta : deltas) {
delta.merge(value);
}
value.commit();
}
reset();
}
private void reset() {
oldValue = null;
deltas.clear();
flags = 0;
setValid(true);
}
@Override
public final void rollback() {
if (isChanged()) {
value = oldValue;
reset();
}
}
@Override
public final boolean isChanged() {
return isFlagSet(CHANGED);
}
protected final void setChanged() {
setFlag(CHANGED);
}
@Override
public boolean isValid() {
if (wrappedEntry != null) {
return wrappedEntry.isValid();
} else {
return isFlagSet(VALID);
}
}
@Override
public final void setValid(boolean valid) {
if (valid)
setFlag(VALID);
else
unsetFlag(VALID);
}
@Override
public boolean isLockPlaceholder() {
if (wrappedEntry != null) {
return wrappedEntry.isLockPlaceholder();
} else {
return isFlagSet(LOCK_PLACEHOLDER);
}
}
@Override
public final boolean isCreated() {
if (wrappedEntry != null) {
return wrappedEntry.isCreated();
} else {
return isFlagSet(CREATED);
}
}
@Override
public final void setCreated(boolean created) {
if (created)
setFlag(CREATED);
else
unsetFlag(CREATED);
}
@Override
public boolean isRemoved() {
if (wrappedEntry != null) {
return wrappedEntry.isRemoved();
} else {
return isFlagSet(REMOVED);
}
}
@Override
public boolean isEvicted() {
if (wrappedEntry != null) {
return wrappedEntry.isEvicted();
} else {
return isFlagSet(EVICTED);
}
}
@Override
public final void setRemoved(boolean removed) {
if (removed)
setFlag(REMOVED);
else
unsetFlag(REMOVED);
}
@Override
public void setEvicted(boolean evicted) {
if (evicted)
setFlag(EVICTED);
else
unsetFlag(EVICTED);
}
@Override
public String toString() {
return getClass().getSimpleName() + "(" + Util.hexIdHashCode(this) + "){" + "key=" + key
+ ", value=" + value + ", oldValue=" + uncommittedChanges + ", isCreated="
+ isCreated() + ", isChanged=" + isChanged() + ", isRemoved=" + isRemoved()
+ ", isValid=" + isValid() + '}';
}
@Override
public boolean undelete(boolean doUndelete) {
if (isRemoved() && doUndelete) {
if (trace)
log.trace("Entry is deleted in current scope. Un-deleting.");
setRemoved(false);
setValid(true);
return true;
}
return false;
}
@Override
public EntryVersion getVersion() {
return null; // DeltaAware are always unversioned! Since concurrent version updates are possible with the FineGrainedAtomicMap
}
@Override
public void setVersion(EntryVersion version) {
// TODO: DeltaAware are always unversioned! Since concurrent version updates are possible with the FineGrainedAtomicMap
}
}