/* This file is part of the db4o object database http://www.db4o.com
Copyright (C) 2004 - 2011 Versant Corporation http://www.versant.com
db4o is free software; you can redistribute it and/or modify it under
the terms of version 3 of the GNU General Public License as published
by the Free Software Foundation.
db4o 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 General Public License
for more details.
You should have received a copy of the GNU General Public License along
with this program. If not, see http://www.gnu.org/licenses/. */
package com.db4o.foundation;
public interface Queue4<E> {
void add(E obj);
E next();
boolean hasNext();
/**
* Returns the next object in the queue that matches the specified condition.
*
* The operation is always NON-BLOCKING.
*
* @param condition the object must satisfy to be returned
*
* @return the object satisfying the condition or null if none does
*/
E nextMatching(Predicate4<E> condition);
Iterator4 iterator();
}