/*******************************************************************************
* Copyright 2014 Analog Devices, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
********************************************************************************/
package com.analog.lyric.dimple.events;
import java.io.IOException;
import java.io.ObjectOutputStream;
import com.analog.lyric.dimple.model.core.FactorGraph;
import com.analog.lyric.dimple.model.core.Node;
import com.analog.lyric.dimple.model.factors.Factor;
import com.analog.lyric.dimple.model.variables.Variable;
import org.eclipse.jdt.annotation.Nullable;
/**
* Base class for events that originate on a {@link FactorGraph} and involve
* a single {@link Factor}.
*
* @since 0.06
* @author Christopher Barber
*/
public abstract class FactorGraphVariableEvent extends FactorGraphEvent
{
private static final long serialVersionUID = 1L;
/*-------
* State
*/
private transient final Variable _variable;
private final @Nullable String _variableName;
/*--------------
* Construction
*/
/**
* @param source of the event
* @param variable involved in the event
* @since 0.06
*/
protected FactorGraphVariableEvent(FactorGraph source, Variable variable)
{
super(source);
_variable = variable;
_variableName = null;
}
/*---------------
* Serialization
*/
private void writeObject(ObjectOutputStream out) throws IOException
{
// Write out _variableName field with non-null value.
out.writeObject(getVariableName());
}
// The default readObject method should work...
/*--------------------------
* FactorGraphEvent methods
*/
@Override
public Node getNode()
{
return _variable;
}
@Override
public String getNodeName()
{
return getVariableName();
}
@Override
protected NodeType nodeType()
{
return NodeType.VARIABLE;
}
/*----------------------------------
* FactorGraphVariableEvent methods
*/
/**
* The variable involved in the event.
* <p>
* Will be null if event was obtained through deserialization.
* @since 0.06
* @see #getVariableName()
*/
public @Nullable Variable getVariable()
{
return _variable;
}
/**
* The name of the factor involved in the event.
* <p>
* The value of {@link Factor#getEventSourceName()} on the
* factor. Unlike {@link #getVariable}, this is preserved by
* serialization.
* @since 0.06
*/
public String getVariableName()
{
final String name = _variableName;
return name == null ? _variable.getEventSourceName() : name;
}
}