/******************************************************************************
* Copyright (c) 2014 Oracle
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* Konstantin Komissarchik - initial implementation and ongoing maintenance
******************************************************************************/
package org.eclipse.sapphire.ui;
import org.eclipse.sapphire.Disposable;
import org.eclipse.sapphire.Event;
import org.eclipse.sapphire.Listener;
import org.eclipse.sapphire.ListenerContext;
import org.eclipse.sapphire.LoggingService;
import org.eclipse.sapphire.Sapphire;
/**
* @author <a href="mailto:konstantin.komissarchik@oracle.com">Konstantin Komissarchik</a>
*/
public abstract class SapphireCondition implements Disposable
{
private ISapphirePart part;
private boolean conditionState;
private final ListenerContext listeners = new ListenerContext();
public static SapphireCondition create( final ISapphirePart part,
final Class<?> conditionClass,
final String conditionParameter )
{
try
{
final SapphireCondition condition = (SapphireCondition) conditionClass.newInstance();
condition.init( part, conditionParameter );
return condition;
}
catch( Exception e )
{
Sapphire.service( LoggingService.class ).log( e );
}
return null;
}
public final void init( final ISapphirePart part,
final String parameter )
{
this.part = part;
initCondition( part, parameter );
updateConditionState();
}
protected void initCondition( final ISapphirePart part,
final String parameter )
{
}
public final ISapphirePart getPart()
{
return this.part;
}
protected abstract boolean evaluate();
public final boolean getConditionState()
{
return this.conditionState;
}
protected final void updateConditionState()
{
final boolean newConditionState;
try
{
newConditionState = evaluate();
}
catch( Exception e )
{
Sapphire.service( LoggingService.class ).log( e );
return;
}
if( this.conditionState != newConditionState )
{
this.conditionState = newConditionState;
this.listeners.broadcast( new Event() );
}
}
@Override
public void dispose()
{
}
public final void attach( final Listener listener )
{
this.listeners.attach( listener );
}
public final void detach( final Listener listener )
{
this.listeners.detach( listener );
}
}