/*
* org.openmicroscopy.shoola.util.concur.tasks.TaskAdapter
*
*------------------------------------------------------------------------------
* Copyright (C) 2006 University of Dundee. All rights reserved.
*
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
* This program 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, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
*------------------------------------------------------------------------------
*/
package org.openmicroscopy.shoola.util.concur.tasks;
//Java imports
//Third-party libraries
//Application-internal dependencies
/**
* Turns a {@link Runnable} into a {@link MultiStepTask}.
*
* @author Jean-Marie Burel
* <a href="mailto:j.burel@dundee.ac.uk">j.burel@dundee.ac.uk</a>
* @author <br>Andrea Falconi
* <a href="mailto:a.falconi@dundee.ac.uk">
* a.falconi@dundee.ac.uk</a>
* @version 2.2
* <small>
* (<b>Internal version:</b> $Revision$ $Date$)
* </small>
* @since OME2.2
*/
class TaskAdapter
implements MultiStepTask
{
/** The adaptee. */
private Runnable task;
/** Tells whether {@link #doStep()} has been invoked. */
private boolean done;
/**
* Creates a new adpter.
*
* @param task The adaptee. Mustn't be <code>null</code>.
*/
TaskAdapter(Runnable task)
{
if (task == null) throw new NullPointerException("No task.");
this.task = task;
this.done = false;
}
/**
* Implemented as specified by the interface contract.
* @see org.openmicroscopy.shoola.util.concur.tasks.MultiStepTask#doStep()
*/
public Object doStep()
throws Exception
{
if (!done) task.run();
done = true;
return null;
}
/**
* Implemented as specified by the interface contract.
* @see org.openmicroscopy.shoola.util.concur.tasks.MultiStepTask#isDone()
*/
public boolean isDone()
{
return done;
}
/*
* ==============================================================
* Follows code to enable testing.
* ==============================================================
*/
Runnable getTask() { return task; }
}