/*
* 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.devices;
import java.security.InvalidParameterException;
import java.util.concurrent.atomic.AtomicBoolean;
import android.content.Context;
import de.unikassel.android.sdcframework.data.Sample;
import de.unikassel.android.sdcframework.devices.facade.SensorDevice;
import de.unikassel.android.sdcframework.devices.facade.SensorDeviceScanner;
import de.unikassel.android.sdcframework.util.ObservableEventSourceImpl;
/**
* Base class for any sensor device scanner type.
*
* @author Katy Hilgenberg
*
*/
/**
* @author Katy Hilgenberg
*
*/
public abstract class AbstractSensorDeviceScanner
extends ObservableEventSourceImpl< Sample >
implements SensorDeviceScanner
{
/**
* the scanned sensor device
*/
private SensorDevice device;
/**
* The active state flag
*/
private final AtomicBoolean isActive;
/**
* Constructor
*/
public AbstractSensorDeviceScanner()
{
super();
isActive = new AtomicBoolean( false );
}
/*
* (non-Javadoc)
*
* @see
* de.unikassel.android.sdcframework.devices.facade.SensorDeviceScanner#setDevice
* (de.unikassel.android.sdcframework.devices.facade.SensorDevice,
* android.content.Context)
*/
@Override
public final void setDevice( SensorDevice device, Context context )
{
if ( device != null && !isCompatibleDevice( device ) )
throw new InvalidParameterException( "Incompatible device type!" );
SensorDevice oldDevice = this.device;
if ( oldDevice != device )
{
if ( oldDevice != null )
{
this.device = null;
oldDevice.setScanner( null, context );
}
this.device = device;
if ( this.device != null )
{
this.device.setScanner( this, context );
}
}
}
/**
* Validation method for a compatible device type
*
* @param device
* the device to test for compatibility
*/
protected abstract boolean isCompatibleDevice( SensorDevice device );
/*
* (non-Javadoc)
*
* @see de.unikassel.android.sdcframework.devices.facade.SensorDeviceScanner
* #getDevice()
*/
@Override
public final SensorDevice getDevice()
{
return device;
}
/*
* (non-Javadoc)
*
* @see
* de.unikassel.android.sdcframework.devices.facade.SensorDeviceScanner#isEnabled
* ()
*/
@Override
public final boolean isEnabled()
{
return isActive();
}
/**
* Setter for the scanner activation state
*
* @param active
* the state to set
*/
protected final void setActive( boolean active )
{
isActive.set( active );
}
/**
* Getter for the scanner activation state
*
* @return the scanner activation state
*/
protected final boolean isActive()
{
return isActive.get();
}
/*
* (non-Javadoc)
*
* @see
* de.unikassel.android.sdcframework.devices.facade.SensorDeviceScanner#enable
* (boolean)
*/
@Override
public final synchronized boolean enable( boolean enable, Context context )
{
if ( enable )
{
// do only start scanner if it is not already running
if ( !isEnabled() )
{
setActive( start( context ) );
}
}
else if ( isEnabled() )
{
// stop a running scanner if enable is == false
setActive( !stop( context ) );
}
return enable == isEnabled();
}
/*
* (non-Javadoc)
*
* @see
* de.unikassel.android.sdcframework.devices.facade.SensorDeviceScanner#onDestroy
* (android.content.Context)
*/
@Override
public void onDestroy( Context context )
{
setDevice( null, context );
// enable( false, context );
}
}