/*
* Copyright (C) 2012, Katy Hilgenberg.
* Special acknowledgments to: Knowledge & Data Engineering Group, University of Kassel (http://www.kde.cs.uni-kassel.de).
* Contact: sdcf@cs.uni-kassel.de
*
* This file is part of the SDCFramework (Sensor Data Collection Framework) project.
*
* The SDCFramework 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 3 of the License, or
* (at your option) any later version.
*
* The SDCFramework 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 the SDCFramework. If not, see <http://www.gnu.org/licenses/>.
*/
package de.unikassel.android.sdcframework.util;
import de.unikassel.android.sdcframework.util.facade.ChainWorker;
/**
* Generic abstract Implementation of the "Chain of Responsibility" pattern.. <br/>
* <br/>
* Extending classes have to implement the {@link #process(Object)} method and
* can override the {@link #doWork(Object)} method if necessary.
*
* @author Katy Hilgenberg
*
*
* @param <T>
* the workers client type
*/
public abstract class AbstractChainWorker< T > implements ChainWorker< T >
{
/**
* The successor
*/
private ChainWorker< T > successor;
/**
* Constructor
*/
public AbstractChainWorker()
{
super();
}
/*
* (non-Javadoc)
*
* @see
* de.unikassel.android.sdcframework.persistence.facade.ChainWorker#doWork
* (java.lang.Object)
*/
@Override
public boolean doWork( T client )
{
// call the workers execution method
if ( !process( client ) )
{
// if execution fails call the successor if there is one
if ( successor != null )
{
return successor.doWork( client );
}
return false;
}
return true;
}
/**
* Processing method of the worker
*
* @param client
* the client
* @return true if successful
*/
protected abstract boolean process( T client );
@Override
public final ChainWorker< T > getSuccessor()
{
return successor;
}
/*
* (non-Javadoc)
*
* @see
* de.unikassel.android.sdcframework.persistence.facade.ChainWorker#setSuccessor
* (de.unikassel.android.sdcframework.persistence.facade.ChainWorker)
*/
@Override
public final void setSuccessor( ChainWorker< T > successor )
{
this.successor = successor;
}
/*
* (non-Javadoc)
*
* @see
* de.unikassel.android.sdcframework.persistence.facade.ChainWorker#withSuccessor
* (de.unikassel.android.sdcframework.persistence.facade.ChainWorker)
*/
@Override
public final ChainWorker< T > withSuccessor( ChainWorker< T > successor )
{
setSuccessor( successor );
return this.successor;
}
}