package org.jacorb.notification.servant;
/*
* JacORB - a free Java ORB
*
* Copyright (C) 1997-2014 Gerald Brose / The JacORB Team.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the Free
* Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import org.jacorb.notification.interfaces.FilterStage;
/**
* @author Alphonse Bendt
*/
public abstract class FilterStageListManager
{
public interface FilterStageList
{
void add(FilterStage filterStage);
}
// //////////////////////////////////////
private final Object lock_ = new Object();
private List checkedList_ = Collections.EMPTY_LIST;
private boolean sourceModified_;
private List readOnlyView_ = Collections.EMPTY_LIST;
// //////////////////////////////////////
public void actionSourceModified()
{
synchronized (lock_)
{
sourceModified_ = true;
}
}
public List getList()
{
synchronized (lock_)
{
refreshNoLocking();
// as readOnlyView_ delegates to checkedList_ sorting
// will also affect the order of readOnlyView_
doSortCheckedList(checkedList_);
return readOnlyView_;
}
}
public void refresh()
{
synchronized (lock_)
{
refreshNoLocking();
}
}
private void refreshNoLocking()
{
if (sourceModified_)
{
final List _newList = new ArrayList();
FilterStageList _listProxy = new FilterStageList()
{
public void add(FilterStage filterStage)
{
if (!filterStage.isDestroyed())
{
_newList.add(filterStage);
}
}
};
fetchListData(_listProxy);
checkedList_ = _newList;
readOnlyView_ = Collections.unmodifiableList(checkedList_);
sourceModified_ = false;
}
}
protected void doSortCheckedList(List list)
{
// No OP
}
protected abstract void fetchListData(FilterStageList listProxy);
}