es.uam.eps.ir.relison.diffusion.propagation.AllRecommendedNeighborsPropagationMechanism Maven / Gradle / Ivy
/*
* Copyright (C) 2020 Information Retrieval Group at Universidad Autónoma
* de Madrid, http://ir.ii.uam.es
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*/
package es.uam.eps.ir.relison.diffusion.propagation;
import es.uam.eps.ir.relison.diffusion.data.Data;
import es.uam.eps.ir.relison.diffusion.data.PropagatedInformation;
import es.uam.eps.ir.relison.diffusion.simulation.SimulationEdgeTypes;
import es.uam.eps.ir.relison.diffusion.simulation.UserState;
import es.uam.eps.ir.relison.graph.edges.EdgeOrientation;
import java.io.Serializable;
import java.util.stream.Stream;
/**
* Given a single piece of information, a user selects all the neighbors who can be reached
* through a recommendation as the destination of the piece.
*
* @author Javier Sanz-Cruzado ([email protected])
* @author Pablo Castells ([email protected])
*
* @param type of the users.
* @param type of the items.
* @param type of the parameters.
*/
public class AllRecommendedNeighborsPropagationMechanism implements PropagationMechanism
{
/**
* The orientation for selecting the neighbors.
*/
private final EdgeOrientation orientation;
/**
* Constructor.
* @param orientation the orientation for selecting the neighbors.
*/
public AllRecommendedNeighborsPropagationMechanism(EdgeOrientation orientation)
{
this.orientation = orientation;
}
@Override
public Stream getUsersToPropagate(PropagatedInformation information, UserState originUser, Data data)
{
U u = originUser.getUserId();
// We select the whole set of neighbors.
return data.getGraph().getNeighbourhood(u, orientation).filter(v ->
{
if(orientation.equals(EdgeOrientation.IN))
{
return data.getGraph().getEdgeType(v, u) == SimulationEdgeTypes.RECOMMEND;
}
else if(orientation.equals(EdgeOrientation.OUT))
{
return data.getGraph().getEdgeType(u, v) == SimulationEdgeTypes.RECOMMEND;
}
else
{
return (data.getGraph().containsEdge(u, v) && data.getGraph().getEdgeType(u,v) == SimulationEdgeTypes.RECOMMEND) ||
(data.getGraph().containsEdge(v, u) && data.getGraph().getEdgeType(v,u) == SimulationEdgeTypes.RECOMMEND);
}
}
);
}
@Override
public boolean dependsOnInformationPiece()
{
return false;
}
}