/*
* Copyright (c) 2002-2009, The DSpace Foundation. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* - Neither the name of the DSpace Foundation nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
* TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
* USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*/
package org.dspace.checker;
import java.util.Date;
/**
* <p>
* A delegating dispatcher that puts a time limit on the operation of another
* dispatcher.
* </p>
*
* <p>
* Unit testing this class would be possible by abstracting the system time into
* an abstract clock. We decided this was not worth the candle.
* </p>
*
* @author Jim Downing
* @author Grace Carpenter
* @author Nathan Sarr
*
*/
public class LimitedDurationDispatcher implements BitstreamDispatcher
{
/**
* The delegate dispatcher that will actually dispatch the jobs.
*/
private BitstreamDispatcher delegate;
/**
* Milliseconds since epoch after which this dispatcher will stop returning
* values.
*/
private long end;
/**
* Blanked off constructor - do not use.
*/
private LimitedDurationDispatcher()
{
end = 0L;
delegate = null;
}
/**
* Main constructor.
*
* @param dispatcher
* Delegate dispatcher that will do the heavy lifting of the
* dispatching work.
* @param endTime
* when this dispatcher will stop returning valid bitstream ids.
*/
public LimitedDurationDispatcher(BitstreamDispatcher dispatcher,
Date endTime)
{
delegate = dispatcher;
end = endTime.getTime();
}
/**
* @see org.dspace.checker.BitstreamDispatcher#next()
*/
public int next()
{
return (System.currentTimeMillis() > end) ? SENTINEL : delegate.next();
}
}