/*
* JBoss, Home of Professional Open Source.
* Copyright 2009, Red Hat Middleware LLC, and individual contributors
* as indicated by the @author tags. See the copyright.txt file 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.jboss.system.server.profileservice.repository.clustered.sync;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.Stack;
import java.util.TreeSet;
import org.jboss.system.server.profileservice.repository.clustered.metadata.RepositoryContentMetadata;
import org.jboss.system.server.profileservice.repository.clustered.metadata.RepositoryItemMetadata;
import org.jboss.system.server.profileservice.repository.clustered.metadata.RepositoryRootMetadata;
/**
* Abstract superclass of classes that generate a list of
* {@link ContentModification} from a pair
* of {@link RepositoryContentMetadata}.
*
* @author Brian Stansberry
*
* @version $Revision: $
*/
public abstract class AbstractContentModificationGenerator
{
// ----------------------------------------------------------------- Public
public List<ContentModification> getModificationList(RepositoryContentMetadata base,
RepositoryContentMetadata modified)
throws InconsistentRepositoryStructureException
{
if (base == null)
{
throw new IllegalArgumentException("Null base");
}
if (modified == null)
{
throw new IllegalArgumentException("Null modified");
}
Collection<RepositoryRootMetadata> baseRoots = base.getRepositories();
Collection<RepositoryRootMetadata> modifiedRoots = modified.getRepositories();
// We validate consistent repository structure by 1) confirming
// same number of roots and 2) (below) confirming all base roots are in modified
if (baseRoots.size() != modifiedRoots.size())
{
throw new InconsistentRepositoryStructureException(base, modified);
}
List<ContentModification> mods = new ArrayList<ContentModification>();
for (RepositoryRootMetadata root : base.getRepositories())
{
RepositoryRootMetadata newRoot = modified.getRepositoryRootMetadata(root.getName());
if (newRoot != null)
{
mods.addAll(getModificationList(root, newRoot));
}
else
{
throw new InconsistentRepositoryStructureException(base, modified);
}
}
return mods;
}
// -------------------------------------------------------------- Protected
protected abstract void handleAddition(String rootName,
RepositoryItemMetadata item, GeneratedModifications mods);
protected abstract void handleMissing(String rootName,
RepositoryItemMetadata item, GeneratedModifications mods);
protected void handleMatch(String rootName,
RepositoryItemMetadata base,
RepositoryItemMetadata modified,
GeneratedModifications mods)
{
// Most common case of all is no change
if (base.equals(modified) == false)
{
// There was a change; how we handle depends on what changed
if (base.isRemoved() && !modified.isRemoved())
{
// Reincarnation
handleAddition(rootName, modified, base, mods);
}
else if (modified.isRemoved() && !base.isRemoved())
{
// Item was removed on the remote node
handleRemoval(rootName, base, mods);
}
else if (base.isDirectory() && !modified.isDirectory())
{
// An exploded archive replaced by a zipped one
handleChangeFromDirectory(rootName, base, modified, mods);
}
else if (modified.isDirectory() && !base.isDirectory())
{
// A zipped archive replaced by an exploded one
handleChangeToDirectory(rootName, base, modified, mods);
}
else if (modified.isDirectory())
{
// Directory timestamp modification
handleDirectoryTimestampModification(rootName, base, modified, mods);
}
else
{
// Simple file change
handleSimpleModification(rootName, base, modified, mods);
}
}
}
protected abstract void handleSimpleModification(String rootName, RepositoryItemMetadata base, RepositoryItemMetadata modified,
GeneratedModifications mods);
protected abstract void handleDirectoryTimestampModification(String rootName, RepositoryItemMetadata base,
RepositoryItemMetadata modified, GeneratedModifications mods);
protected abstract void handleChangeToDirectory(String rootName, RepositoryItemMetadata base, RepositoryItemMetadata modified,
GeneratedModifications mods);
protected abstract void handleChangeFromDirectory(String rootName, RepositoryItemMetadata base,
RepositoryItemMetadata modified, GeneratedModifications mods);
protected abstract void handleRemoval(String rootName, RepositoryItemMetadata base, GeneratedModifications mods);
protected abstract void handleAddition(String rootName, RepositoryItemMetadata modified, RepositoryItemMetadata base,
GeneratedModifications mods);
protected void drainPreapprovedRemovals(GeneratedModifications mods)
{
ContentModification preapprovedRemoval;
while ((preapprovedRemoval = mods.popPreapprovedRemoveParent()) != null)
{
mods.addModification(preapprovedRemoval);
}
}
protected static RepositoryItemMetadata getMarkedRemovedItem(RepositoryItemMetadata base)
{
RepositoryItemMetadata result = base;
if (result.isRemoved() == false)
{
result = new RepositoryItemMetadata(result);
result.setRemoved(true);
}
return result;
}
// ---------------------------------------------------------------- Private
private List<ContentModification> getModificationList(RepositoryRootMetadata base,
RepositoryRootMetadata modified)
{
List<ContentModification> mods = new ArrayList<ContentModification>();
OwnedItem[] items = getOwnedItems(base, modified);
// Track directories that we have added or removed so we can flag
// their children for automatic modification approval/rejection. We
// don't want to add/remove a directory and then later do something
// inconsistent with a child. For stuff involving a removal we use
// a Stack<RepositoryContentModification> so we can add the root removal
// to the overall list of mods *after* all the children. This is needed
// to allow the removal to be rolled back.
RepositoryItemMetadata preapprovedAddParent = null;
Stack<ContentModification> preapprovedRemoveParent = new Stack<ContentModification>();
Stack<ContentModification> prerejectedAddParent = new Stack<ContentModification>();
RepositoryItemMetadata prerejectedRemoveParent = null;
for(int first = 0; first < items.length; first++)
{
GeneratedModifications pairmod = new GeneratedModifications(preapprovedAddParent, preapprovedRemoveParent, prerejectedAddParent, prerejectedRemoveParent);
int next = first + 1;
if (next >= items.length)
{
// Last unmatched item
if (items[first].base)
{
// base w/o match == missing
handleMissing(base.getName(), items[first].item, pairmod);
}
else
{
// !base w/o match == addition
handleAddition(base.getName(), items[first].item, pairmod);
}
}
else if (items[first].itemPath.equals(items[next].itemPath))
{
handleMatch(base.getName(), items[first].item, items[next].item, pairmod);
first++; // we just consumed "next"
}
else if (items[first].base)
{
// base w/o match == removal
handleMissing(base.getName(), items[first].item, pairmod);
}
else
{
// !base w/o match == addition
handleAddition(base.getName(), items[first].item, pairmod);
}
mods.addAll(pairmod.getModifications());
preapprovedAddParent = pairmod.getPreapprovedAddParent();
prerejectedRemoveParent = pairmod.getPrerejectedRemoveParent();
}
// Any remaining mods on our stacks need to be flushed to the list
for (ContentModification mod : preapprovedRemoveParent)
{
mods.add(mod);
}
for (ContentModification mod : prerejectedAddParent)
{
mods.add(mod);
}
return mods;
}
private OwnedItem[] getOwnedItems(RepositoryRootMetadata base, RepositoryRootMetadata modified)
{
TreeSet<OwnedItem> ownedItems = new TreeSet<OwnedItem>();
for (RepositoryItemMetadata item : base.getContent())
{
ownedItems.add(new OwnedItem(item, true));
}
for (RepositoryItemMetadata item : modified.getContent())
{
ownedItems.add(new OwnedItem(item, false));
}
OwnedItem[] ownedItemArray = ownedItems.toArray(new OwnedItem[ownedItems.size()]);
return ownedItemArray;
}
protected static class GeneratedModifications
{
private RepositoryItemMetadata preapprovedAddParent;
private final Stack<ContentModification> preapprovedRemoveParent;
private final Stack<ContentModification> prerejectedAddParent;
private RepositoryItemMetadata prerejectedRemoveParent;
private final List<ContentModification> modifications = new ArrayList<ContentModification>();
public GeneratedModifications(RepositoryItemMetadata preapprovedAddParent,
Stack<ContentModification> preapprovedRemoveParent,
Stack<ContentModification> prerejectedAddParent,
RepositoryItemMetadata prerejectedRemoveParent)
{
if (preapprovedRemoveParent == null)
{
throw new IllegalArgumentException("Null preapprovedRemoveParent");
}
if (prerejectedAddParent == null)
{
throw new IllegalArgumentException("Null prerejectedAddParent");
}
this.preapprovedAddParent = preapprovedAddParent;
this.preapprovedRemoveParent = preapprovedRemoveParent;
this.prerejectedAddParent = prerejectedAddParent;
this.prerejectedRemoveParent = prerejectedRemoveParent;
}
// --------------------------------------------------------------- Public
public void addModification(ContentModification mod)
{
modifications.add(mod);
}
public List<ContentModification> getModifications()
{
return modifications;
}
public RepositoryItemMetadata getPreapprovedAddParent()
{
return preapprovedAddParent;
}
public void setPreapprovedAddParent(RepositoryItemMetadata preapprovedAddParent)
{
if (preapprovedAddParent != null)
{
validateCanCallSet();
}
this.preapprovedAddParent = preapprovedAddParent;
}
public ContentModification peekPreapprovedRemoveParent()
{
return preapprovedRemoveParent.size() == 0 ? null : preapprovedRemoveParent.peek();
}
public ContentModification popPreapprovedRemoveParent()
{
return preapprovedRemoveParent.size() == 0 ? null : preapprovedRemoveParent.pop();
}
public void pushPreapprovedRemoveParent(ContentModification toPush)
{
if (toPush == null)
{
throw new IllegalArgumentException("Null prerejectedAddParent");
}
if (this.preapprovedAddParent != null)
{
throw new IllegalStateException("preapprovedAddParent already set");
}
else if (this.prerejectedAddParent.size() > 0)
{
throw new IllegalStateException("prerejectedAddParent already set");
}
// We allow removing content under something we've rejected
// This happens when RepositoryItemMetadata w/ removed=false needs
// to be pushed to a node
// else if (this.prerejectedRemoveParent != null)
// {
// throw new IllegalStateException("prerejectedRemoveParent already set");
// }
ContentModification peeked = peekPreapprovedRemoveParent();
if (peeked != null && toPush.getItem().isChildOf(peeked.getItem()) == false)
{
throw new IllegalArgumentException(toPush.getItem() +
" is not a child of existing item " + peeked.getItem());
}
this.preapprovedRemoveParent.push(toPush);
}
public ContentModification peekPrerejectedAddParent()
{
return prerejectedAddParent.size() == 0 ? null : prerejectedAddParent.peek();
}
public ContentModification popPrerejectedAddParent()
{
return prerejectedAddParent.size() == 0 ? null : prerejectedAddParent.pop();
}
public void pushPrerejectedAddParent(ContentModification toPush)
{
if (toPush == null)
{
throw new IllegalArgumentException("Null prerejectedAddParent");
}
if (this.preapprovedAddParent != null)
{
throw new IllegalStateException("preapprovedAddParent already set");
}
else if (this.preapprovedRemoveParent.size() > 0)
{
throw new IllegalStateException("preapprovedRemoveParent already set");
}
else if (this.prerejectedRemoveParent != null)
{
throw new IllegalStateException("prerejectedRemoveParent already set");
}
ContentModification peeked = peekPrerejectedAddParent();
if (peeked != null && toPush.getItem().isChildOf(peeked.getItem()) == false)
{
throw new IllegalArgumentException(toPush.getItem() +
" is not a child of existing item " + peeked.getItem());
}
this.prerejectedAddParent.push(toPush);
}
public RepositoryItemMetadata getPrerejectedRemoveParent()
{
return prerejectedRemoveParent;
}
public void setPrerejectedRemoveParent(RepositoryItemMetadata prerejectedRemoveParent)
{
if (prerejectedRemoveParent != null)
{
validateCanCallSet();
}
this.prerejectedRemoveParent = prerejectedRemoveParent;
}
private void validateCanCallSet()
{
if (this.preapprovedAddParent != null)
{
throw new IllegalStateException("preapprovedAddParent already set");
}
else if (this.preapprovedRemoveParent.size() > 0)
{
throw new IllegalStateException("preapprovedRemoveParent already set");
}
else if (this.prerejectedAddParent.size() > 0)
{
throw new IllegalStateException("prerejectedAddParent already set");
}
else if (this.prerejectedRemoveParent != null)
{
throw new IllegalStateException("prerejectedRemoveParent already set");
}
}
}
private static class OwnedItem implements Comparable<OwnedItem>
{
public final boolean base;
public final RepositoryItemMetadata item;
public final List<String> itemPath;
private OwnedItem(RepositoryItemMetadata item, boolean base)
{
assert item != null : "item is null";
this.item = item;
this.itemPath = item.getRelativePathElements();
this.base = base;
}
public int compareTo(OwnedItem other)
{
List<String> ourPath = itemPath;
List<String> otherPath = other.itemPath;
int result = 0;
for (int i = 0; i < ourPath.size(); i++)
{
if (i >= otherPath.size())
{
// We've got extra levels they don't
result = 1;
break;
}
int comp = ourPath.get(i).compareTo(otherPath.get(i));
if (comp != 0)
{
result = (comp < 0) ? -1 : 1;
break;
}
}
if (result == 0 && otherPath.size() != ourPath.size())
{
// They've got extra levels we don't
result = -1;
}
if (result == 0)
{
// base comes before !base
if (base && !other.base)
{
result = -1;
}
else if (other.base && !base)
{
result = 1;
}
}
return result;
}
}
}